SERVICE -­ MELROE  (General) SERVICE LETTERS 1184-11'1-=J +Ml'RO 111-l'llJ DIRECT TO: MELROE IX! bobcof IX! IX! DATE: 20 October, 1997 MODEL: 751, 753, 753H, 763, 763H, 773 and 853, 853H, 873 without Proportional Control SUBJECT: J to L Jumper Wire Assembly (For Attachment Control) A J to L Jumper Wire Assembly (P/N 6714216) is available to improve the performance of the Angle Broom (S/N 690100900 & Above) and Snow Blower attachments It allows the sweep angle to be adjusted while the broom continues to rotate; and the snow blower chute to be positioned while the blower continues to rotate when the Auxiliary Hydraulics are in continuous flow mode The jumper gets power from the "J" terminal of the Auxiliary Controls Module Your Bobcat loader must have the Attachment Controls Option or Kit installed before proceeding with the installation of the J to L Jumper Wire Assembly described in this The J to L Jumper Wire Assembly (P/N 6714216) [A] is three separate wire assemblies Wire number 1 connects between the Attachment Controls Harness and the Loader Controls Harness (See also Wire Number 2 below) Wire number 2 is for Standard Flow loaders and you must install it in the Loader Controls Harness If you have a loader with High Flow hydraulics, the connection at the Loader Controls Harness is already present Wire number 3 is a short jumper wire which is installed into the "J" and "L" holes of the Harness Connector on the attachment Installation of this J to L Jumper Wire Assembly will not affect hydraulically controlled functions of any attachment See page two for installation procedure 1 2 3 I 6114216 only ' 1Wire number 1: -Wire end [aJ Figure [AJ connects to wire end [a1J Figure [BJ -Wire end [bJ Figure [AJ connects to [b1J Figure [CJ (Figure [BJ shows harnesss for loaders with high flow hydraulics) (See Step 2 below for Standard Flow loaders*) -The extra wire is for the stump grinder 2Wire number 2: (Install this wire only ifyou have a Standard Flow loader It is already present on high flow loaders) -Wire end [cJ Figure [AJ is inserted into "J" hole [c1J of the connector for the Auxiliary Controls Module Figure [CJ -Route the wire through the harness so that wire end [b1JeXtends about 4 inches from harness 3Wire number 3: -Insert wire ends [dJ and [eJ Figure [A] into the "J" &"L" holes in the back side (wire side) of the connector on the attachment Figure [D] Attachment Controls Harness 8 (Chassis Part) These four [a1] Three pin connectors J connector are for relays p under cab   J! ,I!unit-ID I 6710300 DIRECT TO: MELROE !XI !XI !XI Service letter DATE: 17 October, 1997 MODEL: 653 (S/N 514811362 & Below) 751 Domestic (S/N 514714842 & Below) 751 Europe (S/N 514912121 & Below) SUBJECT: Improved Performance of Cab Heater The heat output of the Cab Heater can be improved by replacing the elbow (Item 1) [A] (P/N 6713983) at the inlet of the radiator The smaller inside diameter of the elbow reduces the by-pass flow to help obtain higher engine temperature Check your loader to see if the new elbow, and new muffler mounting bracket, was previously installed If the new muffler mounting bracket has been installed [B], the loader already has this new elbow If the muffler mounting bracket has not been installed, we recommend that it be installed along with other parts to complete the installation (See BTI 311 for complete instructions and part descriptions) A higher temperature thermostat (P/N 6669032) is also available The thermostat will improve heater performance only if the new elbow has been installed  only DIRECT TO: MELROE 00 00 00 SAFETY NOTICE DATE: 9October1997 MODEL: 607, 709, 709FDS, 8709, 811 Backhoe (See Serial Numbers On Page Four) SUBJECT: NEW BACKHOE CHAIN ASSEMBLY NOTE: This Service Letter replaces Service Letter dated 11 July, 1997 The procedure and drawings are revised to clarify correct washer (P/N 27E6) quantity and use A Safety Notice dated 4 June 1997 was sent to owners of model 607, 709, 709FDS, 8709, and 811 Backhoes that have serial numbers listed on page four This Safety Notice informed owners of a safety concern and that their dealer will contact them to have their machine corrected ' Mel roe Company has developed a chain assembly and decals for the backhoe models listed above which is supplied at no cost to the owner The chain assembly and decals must be installed on all backhoes with serial numbers listed This chain assembly and decals are installed in all current production model 607, 709, 709FDS, 8709, and 811 backhoes Melroe Company now asks its dealers to immediately take the following actions: 1 2 Contact all owners of affected backhoes and make arrangements to install the chain assembly and decals on the backhoe attachment 3 	 Instruct the owner about the chain assembly and decals and complete the Installation and Instruction Report 4 Install the chain assembly and decals on all affected backhoes in your dealer inventory Dispose of the original Operation & Maintenance Manual and replace it with the new manual provided Installation Procedure: Use the reference in drawing A and below to locate the position to drill one 13/32 inch (1 O mm) hole in the backhoe mounting frame NOTE: The hole location is determined by model Use the correct location for each model Model Model 607, 709, Ref 811 709FDS 8709 1 15 inch (38 mm) 175 inch (44 mm) 2 50 inch (127 mm) 250 inch (64 mm) Push the hoses forward and restrain them Mark the location Drill the Hole Installation Procedure (cont'd) 8 Bolt Through Third Link Install the guide, safety chain and hitch pin wire to the backhoe frame with the bolt washers and nut as shown in drawing B ' 1:he hain mul!t be bolted through the third lmkm the cham as shown Position the long end ofthe guide to the front as shown NOTE: Use the guide on models 607 709 -709FDS, and 8709 Use the wshe: on model 811 only Do not use the guide and washer together Clean the front of the mounting frame Install the Warning decal (P/N 6714920) as shown in drawing C Clean the back of the seat Install the Attaching D And Removing The Backhoe decal as shown in drawing D Use decal (P/N 6714916) for model 8709 and decal (P/N 6714915) for the other models Clean the mounting frame Install the Warning decal (P/N 6714911) as shown in drawing D Complete the Safety Chain Installation And Instruction Report with the customer The installation is complete  forthree fourths (3/4) hour labor to install the safety chain One (1) additional hour is allowed for travel time for retailed machines When filing warranty claims electronically use service code 01 R75 A signed Installation andInstruction Report (white copy) must be returned to Me/roe Company Retain the yellow copy for your dealer file This field modification requires your immediate attention SERVICE LETTER PACKING LIST so1no91 8709 811 709FDS Ref Part No Description Qty Qty Qty 1 Chain Assembly 1 0 1 (49 1/2 inch) Chain Assembly 0 1 0 (55 1/2 inch, Blue co/of') 2 6714839 Guide 1 0 1 3 27E-6 Washer 1 2 1 4 17C-636 Bolt 1 1 1 5 85D-6 Nut 1 1 1 6 6661838 Hitch Pin 1 1 1 7 6714916 Decal 1 0 0 6714915 Decal 0 1 1 ,,,---  8 9 10 11 6714920 6714911 6900406 6900404 6900405 6900407 Decal Decal Manual Manual Manual Installation Report 1 1 1 0 0 1 1 1 0 1 0 1 1 1 0 0 1 1 3 Install the Chain Assembly and Decals on Backhoes with the following serial numbers: Model 	Serial Number 880000101-880000225, (Except220) 880000229 607 	775000101-775001723, (Except1719, 1720) 775001729-775001734, (Except1731, 1733) 811 	630000101-630002060, (Except2007) 630002063-630002074, (Except2070,2072,2073) 630002077 709 	270000101-270000237, 270000301-270005302, (Except5076,5259,5269,5291,5299,5301) 270005311,270005327,270005342,270005365,270005368, 270005375-270005377 709FDS 	584100101-584100731 (Fold Down Stabilizers) 11' DIRECT TO: MELROE !XI GERSOLL-RAND Iii IX! Serviceretfer DATE: 	18 September, 1997 MODEL: 	553 (SIN 513011001 -513013999) 553 (SIN 513031001 -513033999) Europe Only SUBJECT: 	Improved Hydraulic Filter Seal Melroe Company has determined that increased back-pressure in the charge circuit can occur in certain applications and reduce the service life of the filter seal A higher pressure hydraulic filter assembly and larger diameter plumbing is now available to increase the service life of the filter seal This filter assembly is designed for higher pressures to provide improved filter seal and the larger diameter plumbing provides less back-pressure in the the charge circuit If you are servicing a loader for the hydraulic filter seal, we recommend installing the new filter head assembly and plumbing as listed below J" Service Letter Parts List P/N DescriQtion Qty Ref *6714081 Hose 1 A 1302104 Fitting 2 B 6661334 Filter Assembly 1 c 1C612 Bolt 2 D 6714359 Tubeline 1 E NOTE: 	*Hose (PIN 6714081 Ref A) is factory installed on loaders SIN 513013030 & Above and 513033288 & Above (Europe only) See page two for parts installation procedure r Installation Procedure: Refer to the Loader Service Manual as necessary for details of procedures outlined below Raise the operator cab Disconnect the hose between the port block and the charge inlet of the hydrostatic pump Replace the hose with the new, larger diameter hose (A) Open the rear door Remove the rear screen Remove the hydraulic filter housing Dispose of the housing, fittings and mount bolts Remove and dispose of the tubeline that connects the oil cooler to the hydraulic filter housing Cap and plug the cooler and hose Use the reference in the drawing and below to locate the position to drill two 13/32 inch (10 mm) holes in the mainframe Mark the location and drill the two holes Ref 1 425 inch (108 mm} Ref 2 14 inch (36 mm} Ref 3 15 inch (38 mm} Install the new fittings (B} in the new filter head (C) Position the filter outlet fitting down and tighten it to the filter head Connect and tighten the existing hose (plugged earlier) to the outlet fitting Use the two bolts (D) and mount the filter head assembly to the mainframe in the new location NOTE: The filter head must be installed with the inlet to the rear of the loader The filter head is clearly marked on top with arrows The sender is not used Install and tighten the new tubeline (E) between the cooler and the filter inlet fitting Tighten the inlet fitting to the filter head Litt and block the loader Use the remote start switch (MEL 1429} to start the loader and check the connections for leaks Install the rear screen Close the rear door Lower the operator cab The installation is complete Filter Head Inlet Rear Of Loader DIRECT TO: MELROE 00 00 00 DATE: 15 July 1997 MODEL: 863, 863H, and 873 without Bobcat Operation Sensing System (BOSS) SUBJECT: Engine Temperature Sensor Recently the current production engine temperature sensor (P/N 6666613) was not available from the supplier An alternate sensor was installed on some model 863, 863H and 873 loaders This only applies to loaders without Bobcat Operation Sensing System (BOSS) This sensor has two spade connectors and uses a short harness to adapt the sensor to the engine wire harness The alternate sensor and harness are not available as a replacement part When servicing a loader for sensor replacement, order a replacement sensor per the parts book If an alternate sensor is replaced, dispose of the adapter harness The information provided below is for service of this alternate sensor Sensor Service Information: Use only the large spade to connect to the adapter harness The sensor is grounded through its body To test the sensor for proper resistance, check between the body of the sensor and the large spade only Do not use the small spade on this sensor The test resistance of the alternate sensor is similar to the normally used sensor Engine Temperature Sensor Test Values* 70 degree F (21 degree C) 970 ohms 80 degree F (27 degree C) 1013 ohms *Resistance tests will vary slightly depending on conditions DIRECT TO: · · MELROE 00 bobmf 00 00 I DATE: 	30 June, 1997 MODEL: 	873 (SIN 514115001 & Above) 873 (S/N 514213000 & Above) Europe Only SUBJECT: 	SERVICE SHIELD MEL1531 Melroe Company has developed a shield to use when adjusting the steering neutral setting on model 873 loaders with the manual (non-servo) hydrostatic pump The shield covers the drive belt and pulleys while adjustments are made The shieldmust be used when making this adjustment The steering neutral adjustment is made through the left and right side access covers The shield is used when adjusting the left side only Melroe Company is providing a shield to each dealer Additional shields can be ordered from OTC Service Tools under part number MEL1531 Follow the procedure /' listed below to install the shield Shield Installation Procedure: Turn the ignition switch to the off position and remove the key Remove the two bolts and swing the left side access panel forward Rotate the fan drive tension pulley forward and remove the fan belt from the hydrostatic pump pulley and fan gearbox pulley Place the fan belt up and rearward out of the work area The belt will remain disconnected while the neutral adjustment is made Rotate the fan drive tension pulley forward and install the shield as shown The inside edge of the shield must rest on top of the engine/pump mount forward and behind the tension pulley The outside edge must rest on the main frame as shown The tab on the shield must rest inside the main frame to hold the shield in position (see photo) The new 873 Service Manual (P/N 6900390) will include this procedure and will be available soon and sent to all dealers Until the new Service Manual is available use the Steering Neutral Adjustment procedure from the 753 BICS Service Manual (P/N 6900105) JSL873Tool6197 Printed in USA DIRECT TO: : , MELROE IXI IXI 1X1 J Service letter FIELD MODIFICATION DATE: 15 May 1997 MODEL: 58 Landscape Rake (S/N 910700101-00472) 68 Landscape Rake (S/N 063000101-00375) SUBJECT: Hydraulic Motor Timing and Hose Routing Melroe Company has determined that some hydraulic motors are timed for incorrect rotation The correct rotation is counterclockwise viewed from the output shaft end The rake bars must rotate to pull into the bucket If you have a rake with incorrect rotation check for correct hose routing before re-timing the hydraulic motor Use the following procedure to correct it Hose Routing Procedure: Check the hose routing The hoses going to the hydraulic motor must not cross The male coupler on the rake must connect to the right side inlet fitting (Item 1) on the port block The right side outlet fitting (Item 2) on the port block must connect to the right side port (Item 3) of the hydraulic motor Continued on the reverse side JSLRAKES/97 Routing Procedure (Cont'd) The male rake coupler routs oil to port A on the hydraulic motor for counterclockwise rotation of the rake when the loader front hydraulics is put in the continuous operation (detent) mode If the hose routing is correct and the rotation is incorrect, incorrect the hydraulic motor timing is Timing th e Hydraulic Motor See the Attachment Service Manual for hydraulic motor removal, disassembly and assembly procedures NOTE: The service manual timing procedure shows for clockwise rotation for the angle broom Use the procedure provided below for the landscape rake Align the drain hole in the valve plate with the drain hole in the geroler ring The 0-ring side of the valve plate faces toward the geroler Mark the outside of the sections Find the largest opening between the geroler star and the geroler ring Make sure the slot opening of the valve plate is aligned with the largest opening of the geroler Install the valve plate assembly Install the valve on the valve plate Align any one of the six outside ports with the mark on the geroler ring Turn the valve counterclockwise a small amount until the teeth on the valve drive shaft engage the valve Motor timing is complete Continue the assembly of the motor Rotate Valve Counterclockwise 1/2 Tooth to Engage Spline Mark this timing correction for landscape rake on page 1A-14 of the Attachment Service Manual The Manual procedure listed is correct for angle broom Mel roe Company will give warranty compensation for one (1) hour labor to repair each rake One (1) additional hour is allowed for travel time for retailed machines This offer expires June 1998 When filing warranty claims electronically use service code 01 R74 DIRECT TO: MELROE 00 00 00 FIELD MODIFICATION DATE: 2 April 1997 MODEL: 15 Auger (SIN 187400101-187400672) 15H Auger (S/N 187500101-187500136) & (187500143-187500147) 30 Auger (S/N 187600101-187600438) 30H Auger (S/N 187700101-187700128) SUBJECT: Improved Auger Output Shaft Sealing Melroe Company has developed an improved method of shaft sealing Current production augers have a new housing that uses a back-up washer for improved 0-ring service life The housing part number has not changed If you are replacing an output shaft 0-ring in an auger in the serial number range listed above, use the parts and procedure listed below Order the following parts: P/N Description Qty 25K-40608 0-ring 1 6711242 Housing 1 25K-40224 0-ring 1 SOK-232 Back-Up Washer 1 Replacement Procedure: Remove the auger bit Remove the auger from the auger frame (if used on a loader) or excavator (See Auger Operation & Maintenance Manual) Support the auger Remove the nut and retainer bolt from the pivot pin on the motor mount Remove the pivot pin and pivot bracket from the motor mount Remove the two bolts and top cover Mark the fittings for proper hose location Remove the hoses and cap the fittings Remove the eight bolts located on the bottom of the motor mount JSLAUGER3/97 Replacement Procedure (Cont'd): Remove the motor drive assembly from the mount Remove the eight motor mount bolts Lift the motor from the drive housing assembly Remove the shaft, washers and bearings from the drive housing Discard only the drive housing and 0-rings The shaft is hardened Inspect the shaft for a smooth finish Check the shaft in the seal area and on the larger diameter that runs in the housing Both areas of the shaft must be smooth Use 500 grit abrasive cloth to clean the shaft Thoroughly clean and inspect all parts before reassembly Replace damaged parts Put hydraulic oil on the small 0-ring (P/N 25K-40224), back-up washer (P/N BOK-232) and on the inside diameter of the new drive housing Install the small 0-ring and back-up washer in the drive housing I I <O> Upper : Washers,  I g- Lower ? Motor Mount Bolts Bearing Shaft Washers ?--Bearing <O> I 6 ,  Large 0-ring I I ,  Drive Housing I I C? ,  Small 0-ring <C?> ,  Back-up Washer Put oil on the large 0-ring (P/N 25K-40608) and install it on the pilot diameter of the motor Put oil on the lower washers and bearing and install them in the drive housing Install the auger shaft in the drive housing Put oil on the upper washers and bearing and install them on the auger shaft Install the motor on the drive housing assembly Install and tighten the eight mount bolts to 110 ft-lbs (150 Nm) torque Install the motor drive assembly to the mount Install and tighten the eight mount bolts to 70 ft-lbs (95 Nm) torque Install the hoses Install the top cover and two mount bolts Install the pivot bracket and pivot pin to the motor mount Install the retainer bolt and nut to the pivot pin Install the auger bit Check for correct operation and for leaks The procedure is complete  for two (2) hours labor to repair each auger One (1) additional hour labor is allowed for travel time for retailed machines This offer expires April, 1998 No pre-printed warranty claims will be sent File using regular warranty claims or electronically Use service code 01 R73 DIRECT TO: ,/ / MELROE ,/ bobcat Service letter DATE: 	14 March 1997 MODEL: 	331 EXCAVATOR (SIN'S 512913001 -512913488) Except SIN's 13469, 13477, 13479, & 13486 325 EXCAVATORS (SIN'S 514013001 -514013579) Except S/N's 13565 & 13577 SUBJECT: JOYSTICK PILOT PRESSURE INCREASE NOTE: This Service letter replaces Service Letter dated 10 February 1997 The model numbers are now corrected to match the serial numbers affected The pressure  adjustment procedure is revised The joystick pilot pressure has been increased in current production model 325 and 331 excavators The new joystick pressure is 365 PSI (2517 kPa) The old joystick pressure was 325 PSI (2241 kPa) This increased pressure ensures the bucket and dipper hydraulic control spools can travel their entire stroke This reduces bucket and dipper arm cycle time and improves dipper arm function performance If you are servicing a machine with a serial number listed above, the pressure can be increased to improve performance Joystick Pressure Adjustment Procedure: Warm up the hydraulic system oil Run the hydraulic functions over relief for 10­ 20 second intervals for ten minutes Fully lower any attachment, turn the engine off and remove the key Remove the two floormat threshold mounting bolts and spacers Remove the threshold, floormat and front floor cover Continued on the reverse side 331JOYP DOC Printed in USA 1 Two hoses are connected to the port B tee fitting Remove one of the hoses from the tee fitting and plug the hose (see photo of manifold removed for clarity) Install a 1000 PSI gauge to the tee fitting where the hose was removed Put the swing lock lever in the engaged (locked) position Lower the left side joystick control panel Start the engine and run at high idle Pull the blade control lever back to fully raise the blade Hold the lever back to raise the pressure over relief This will raise the pressure at the manifold inlet Loosen the jam nut on the relief valve Adjust the valve until the pressure on the gauge is 365 PSI (2517 kPa) Tighten the jam nut Recheck the pressure Adjust if needed Turn the engine off and remove the key Remove the gauge and connect the original hose onto the tee fitting Start the engine and run at high idle Operate the excavator joystick controls and check for proper operation Replace the front cover, floormat and threshold  only 2 DIRECT TO: / / MELROE / bobcat DATE: 14 March 1997 MODEL: 331 EXCAVATOR (SIN'S 512913001 -512913488) Except SIN's 13469, 13477, 13479, & 13486 325 EXCAVATORS (SIN'S 514013001 -514013579) Except SIN's 13565 & 13577 SUBJECT: JOYSTICK PILOT PRESSURE INCREASE NOTE: This Service letter replaces Service Letter dated 10 February 1997 The model numbers are now corrected to match the serial numbers affected The pressure adjustment procedure is revised The joystick pilot pressure has been increased in current production model 325 and 331 excavators The new joystick pressure is 365 PSI (2517 kPa) The old joystick pressure was 325 PSI (2241 kPa) This increased pressure ensures the bucket and dipper hydraulic control spools can travel their entire stroke This reduces bucket and dipper arm cycle time and improves dipper arm function performance If you are servicing a machine with a serial number listed above, the pressure can be increased to improve performance Joystick Pressure Adjustment Procedure: Warm up the hydraulic system oil Run the hydraulic functions over relief for 10­20 second intervals for ten minutes Fully lower any attachment, turn the engine off and remove the key Remove the two floormat threshold mounting bolts and spacers Remove the f' threshold , floormat and front floor cover Continued on the reverse side 331JOYP DOC Printed in USA 1 Two hoses are connected to the port B tee fitting Remove one of the hoses from the tee fitting and plug the hose (see photo of manifold removed for clarity) Install a 1000 PSI gauge to the tee fitting where the hose was removed Put the swing lock lever in the engaged (locked) position Lower the left side joystick control panel Start the engine and run at high idle Pull the blade control lever back to fully raise the blade Hold the lever back to raise the pressure over relief This will raise the pressure at the manifold inlet Loosen the jam nut on the relief valve Adjust the valve until the pressure on the gauge is 365 PSI (2517 kPa) Tighten the jam nut Recheck the pressure Adjust if needed Turn the engine off and remove the key Remove the gauge and connect the original hose onto the tee fitting Start the engine and run at high idle Operate the excavator joystick controls and check for proper operation Replace the front cover, floormat and threshold  only 2 DIRECT TO: MELROE  !XI , bobcat INGERSOLL-RANP !XI Parts, Manager ' · !XI Bobcat Specialit : r  ' SAFETY NOTICE = /IJ !\ ' DATE: 13 March 1997 MODEL: 325 Excavator (S/N's 511820520 -511821184) & (S/N's 514011001 -514011544) & (S/N's 514013001 -514013748) 331 Excavator (S/"1i's 512913001 -512913867)  ,, i· ; : : ; ; SUBJECT: Boom Swing Cylinder and Control Vlve ,  ·'  ' \ ' NOTE: This Service Letter replaces Service Letter dated 27February1997l'tle serial numbers  I I -w ' '}-' on model 325  are revised The procedure and pictures are revised to clarify · correct installation "'9,f'par:ts for model 325 and 331 - :=: ·: L ,';··· ::n ,' , i ; ,  : , / I'"; l,; '1 · A Safety Notite dated 20 Februar}#"1997 was sent to owners of Model 325 and 331 Excavators that have serial numbers listed above Th'is Safety Notice informed owners of a safety concern and to contact their dealer-to have their machine corrected Mel roe Company asks its dealers to immediately contact all ownrSr of ·affected excavators apd· make arrangements for this repair and correct all affected excavaors in your dealer inventor:¥,{\':'; ,;; :,:·,, , , ,!: r ," The affected machines require the replacement of the poppets in the swing valve section of the control valve and/or installation of an orifice in the swing cylir,ideP!lJrpqing All {TJachinesdo not require the same procedure See the'model ahd ser/a(humb'ers tlstec:ibefow toleach procedure  - , ; ,-· : , " r-: : i - Replacement of poppets and 0 -rings in control valve S'hd lrillation of cylinder orifice Model 325 (S/N 511820520 -511821184), & (S/N 514011001 -514011544) &  ·c ,  "" ,  , ' i  'lo I "\ ', ' (S/N 514013001 -514013739)" · · · ' · " - Model 331 (S/N 512913001 -512913839 and 13841) :;, != ·,r 31 ··: '!L Installation of cylinder orifice only Model 325 (S/N 514013740-514013748) Model 331 (S/N 512913842 -512913867) Service Letter Parts List PIN Description Qty Ref 6670696 Poppet 2 A 6665471 0-ring 2 B 6569312 Orifice (0107 inch) 1 C 6532775 Orifice (0082 inch) 1 D NOTE: Orifice (P/N 6569312) is colored blue for identification and used on model 331 only Printed in USA JSLXSWING3197 1 Fully lower any attachment, turn the engine off and remove the key Remove the two floormat threshold mounting bolts and spacers Remove the threshold and floormat, Remove the four mounting bolts and front floor cover Find the boom swing section of the hydraulic control valve I · , , Machine S/N's (51820520 -511821184) and (514011001 -514011544) It is the front section of the 3 spool valve See photo A Machine S/N's (514013001 -514013739) It is the center section of the 5 spool hydraulic yontrol valve See photo B Remove the end plug, spring and poppet from both ends of the valve section Use a magnet to remove the oppet Discard the poppet Replace the o-rings (P/N 6665471) on the end plugs Install the new poppets (P7N 6670696fand the ­springs removed earlier Install the end plugs and tighten Model 325 Installation of boom swing cylinder orifice Fully lower any attachment, turn the engine off and remove the key Remove the two floormat threshold mounting bolts and spacers Remove the threshold, floormat and front floor cover -----· -- - ·--·--· -----­ Disconnect the-rod end pe, frq,rxi tp WiQg "' cylinder · "<" "-··J · 1 => · -· , i Machine S/N's (511820520 -5118it(ijID it1lf' \·;':· (514011001 -514011544) have an1'drifice 1 ·­Remove the existing orifice and discard it Install the orifice (P/N 6532775) in the connection and tighten Use a small amount of grease to hold the orifice in place , Poppet iu'l -·, (j ,       0-ring Model 331 , Replaceme » · ·ets and 0-rings  , Fully lower an -el")t, turn the engine off; and remove the' I< · ,, ''"" ' \t:t"',· ' ' Remove the ·two:, lbormat threshold mounting bolts and spacers Remove the threshold and floormat Remove the four mounting bolts and front floor cover Find the boom swing section of the hydraulic control valve It is the center section of the 5 spool valve located on the left side of machine Remove the end plug, spring and poppet from both ends of the valve section Use a magnet to remove the poppet Replace the o-rings (P/N 6665471) on the end plugs Discard the removed poppets Install the new poppets (P/N 6670696) and the springs removed earlier Install the end plugs and tighten Model 331 Installation of boom swing cylinder orifice Position the boom swing in center Fully lower any attachment, turn the engine off and remove the key Work through the swing cylinder opening in the upperstructure Find the boom swing cylinder hoses pictured Mark the rod end hose and tubeline before disassembly Disconnect both rod and base end hoses Install the orifice (P/N 6569312) in the base end connection and tighten This orifice is blue in color Use a small amount of grease to hold the orifice in place Install the orifice (P/N 6532775) in the rod end connection and tighten ·I '·j : t · ,: : ,· , r Install Base 1r i 1End Orifice 1 / ,')-----Here Install Rod u; End Orifice """""' Here 1· ' i -  on excaOhtot'thodls gJTitd-below Replacement of poppets/0-rings and Installation of cylin(:ir orijicn ,-, ,    1 - Model 325 and 331 0ne and one half (1-1/2) h0llfoo;· ·;;·,::> '· · 1  :  ,I Installation of cylinder orifice only Model 325 0ne (1) hour Model 331 0ne half (1/2) hour labor One (1) additional hour of labor is allowed for travel time for retailed machines When filing warranty claims electronically use service code EXR53 Ull'\C\, I IV / / MELROE / INGERSOL-RAND 	bobcat ' i '- ' DATE: 10 February 1997 MODEL: 	325 EXCAVATOR (SIN'S 512913001 -512913488) Except S/N's 13469, 13477, 13479, & 13486 331 EXCAVATORS (SIN'S 514013001 -514013579) Except S/N's 13565 & ' 13577 SUBJECT: JOYSTICK PILOT PRESSURE INCREASE The joystick pilot pressure has been increased in current production model 325 and 331 excavators The new joystick pressure is 365 PSI The old joystick pressure was 325 PSI This increased pressure ensures the bucket and dipper hydraulic control spools can travel their entire stroke This reduces bucket and dipper arm cycle time and improves dipper arm function performance If you are servicing a machine with a serial number listed above, the pressure can be increased to improve performance Joystick Pressure Adjustment Procedure: Warm up the hydraulic system oil Run the hydraulic functions over relief for 10-20 second intervals for ten minutes Fully lower any attachment, turn the engine off and remove the key Remove the two floormat threshold mounting bolts and spacers Remove the threshold, floormaf and front floor cover ,, ' Continued on the reverse side "t 331JOYP OOC Printed in USA  ·1 1i-' r , --,,"\ Ir , ' Lower the left side joystick control panel· Start the :-engiri'e and run at high' idle -4-"·- I n-tr 1-Pgi-2d -PrtT-mi? h  ·y; J· ; ,; ; ··· ·----· - -· · · -··· · Jo ' ": ·· ·-;\(-} ;  ;- ' · ·: -·  ·· l, Operate the excavator joystick controls and che,c:fqr, propr operation r:  , ' \BB ;· 'J- : - t : ·:--t Replace the front cover, floormat and threshold , 2 · ': f '  I DIRECT TO: v" "' - -I' bobcat s·e:rv·iceletter DATE:· 24 January 1997 , : MODEL: All 331 EXCAVATOR  , SUBJECT: WATER DRIP RAlt A foam water drip rail js now available tor model 331 excavators The drip rail diverts water away from the fan beltarea We are aware that some model 331 excavators have had water:drip, dpwn onto the fan belt and freeze When the $ngine is started, the fan belt may come ofUtie pulley Engine overheating may resutt  	­ "°"' 	If you encounter this condition in freezing climates, we 'recpmmend installing a new water 9rip'raiJ; Qrder bulk drip rail (PIN 667053t-qv§lrlty 12 jnches) from Melroe Parts Sales · Theddp'-rail}i a,s a self adhesive backing To install' the drip rail, open the rear door Clean the:area where the drip rail will be · located Remove the paper backing and press the foam drip rail in pla(;e The drip rail should slope down toward the engine as shoym to drain water away from the fan Install the ·endof the drip rail 3 inches from the plastic shield as shown The;at>9"'e is: provided as technical information: Notmal warranty policy t ; applies · · 331 DRIPDOC Printed in USA ti ,, '  'J '"  '1 ·tt i'f '- -  i · , 1k·:u' ) ;: -:, · 11 · ' : , 'r " ·1; r)::': i:"'· t  · " 'I ·, :i  ' : : ·1r1 :,1 t i; -t·:Jv": ·, :i; -:· ' ' ·::!°\ l: H:· ' ' ' ;i'j , - ! :;t,",'' , ·'' " \If' -·::,I, ' ' :; ,,;,;;  'i: :i:3 i ':f,1£«10 ,, ·; ,' i "';,' ' J \ : ·' i -·· ·,-A ( ·,·i · · S ·:·;'' ·, o "' ·' i ; 1-: 1 ·:; :: ;lt· t: nto:\" ·'·i -, i i t"; ': :' ;rn!m'l; "· ' 0: 1 l DIRECT TO: ,/ / PX MELROE 	 / 	bobcat DATE: 5December1996 MODEL: 751 (S/N 514713990 AND BELOW) -DOMESTIC ONLY SUBJECT: CRANKSHAFT SEAL REPLACEMENT (FLYWHEEL END) When replacing the flywheel end crankshaft seal under warranty, on a machine listed above, we recommend the following: 1 	 If the seal is being replaced because of a leak between the crankshaft and the seal, replace the seal (P/N 7000005) and the flywheel assembly (P/N ·6709768) Retain the flywheel and seal at your dealership for possible warranty return 2 	 If the seal is being replaced because it has pushed out from excess crankcase pressure, replace the seal only DO NOT replace the flywheel assembly NOTE: Only install a current 394 inch (10 mm) wide crankshaft seal (P/N 7000005) DO NOT install an old 275 inch (7 mm) wide crankshaft seal  Normal warranty policy applies -51SEAL DOC Printed in USA DIRECT TO: / / MELROE 	 / 	bobcat DATE: 	4December1996 MODEL: 	450 (S/N 561711932 AND BELOW) 453 (S/N 561811771 AND BELOW) 450 EUROPEAN (S/N 562011283 AND BELOW) 453 EUROPEAN (S/N 561912215 AND BELOW) SUBJECT: HYDROSTATIC RELIEF/REPLENISHING VALVES 4000 PSI hydrostatic relief/replenishing valves are now installed in current production model 450 and 453 loaders The relief/replenishing valves are installed in the forward drive circuit only The relief/replenishing valves provide additional protection of the hydrostatic motor under extreme loading conditions by limiting the hydrostatic pressure If you are replacing the drive motor(s) in an earlier model 450 or 453 loader (see serial numbers above) because of a possible high loading condition, we recommend also installing new hydrostatic relief/replenishing valves in the forward drive circuit Order the following from Melroe Parts Sales P/N Description Qty 6632063 Relief/replenishing Valve 2 6513479 Cap and Spring 2 Remove the existing forward replenishing valves Install the new relief/replenishing valves spring and cap Continued on the reverse side -----	--·-· -------·· ·-·--------­  	' ::c A ' 	'r-V Rehef/replenishmg Valves 450REL DOC Printed in USA 1 The new relief/replenishing valves install in the locations shown Front of Loader B-6422 Remove the existing cap, spring and replenishing valve Install the new relief/replenishing valve, spring and cap in both pumps  Normal warranty policy applies 2 , DIRECT TO: 1AELROE !XI '°  , !XI !XI FIELD MODIFICATION DATE: 2December1996 MODEL: 873 SUBJECT: DRIVE IMPROVEMENTS (SHUNT HOSE KIT AND MOTOR SEAL KIT) Two improvements have been developed for the model 873 loader If a model 873 loader experiences momentary loss of drive in the reverse direction when operating at or near maximum load, we recommend installing both improvements The shunt hose kit provides improved flow in the reverse drive relief circuit An improved seal kit provides improved motor operation Order the following parts from Melroe Parts Sales: P/N Description Qty 6713458 Shunt Hose Kit 1 6666357 Motor Seal Kit 2 55K-21 0-Ring 6 3GM-12100 Bolts 2 SHUNT HOSE KIT INSTALLATION Lift and block the loader Refer to the Service Manual Page 1-4 NOTE: If the lift arms are raised to perform this procedure, remove any attachment and install the lift arm support device Refer to the Operation and Maintenance Manual or instructional decal on the side of the operator cab 873SHUNTDOC Printed in USA Raise the operator cab Refer to the Operation & Maintenance Manual Drain the hydraulic fluid into a clean container A reservoir drain hose is located behind the left side motor cover Remove the left side motor cover Pull the reservoir drain hose out of the side of the · loader frame Remove the hose end cap and drain the fluid into a clean container Clean the area around drive hoses at the pump Disconnect the four drive hoses at the hydrostatic pump set After disconnecting hoses, cap and plug open hoses and ports to prevent contamination Move the hoses aside Remove the two lower fittings from the hydrostatic pump set (see photo) Install the two new fittings (P/N 6713448) in the lower ports Do not tighten them at this time Install two straight fittings (P/N 15K-5) onto the lower drive fittings on the hydrostatic pump The hydrostatic pump set is shown removed for photo clarity Install the two new hoses (P/N 6669987 & 6669988) onto the fittings as shown The 90° hose end connects to the left side fitting as viewed from the operator seat Remove the two plugs located directly above the rear drive relief valves Install the remaining straight fitting (P/N 15K-5) and elbow fitting (P/N 6558510) in the ports as shown Note that the hydrostatic pump set is viewed from the rear of the loader Connect the other end of the shunt hoses to the fittings as shown Route the hoses to provide maximum clearance with the pump linkage and corners of the hydrostatic pump set Tighten fil! fittings and hoses Correct shunt hose installation as viewed from the front of the loader ,,- 	Install new 55K-21 o-rings on the top drive fittings Lubricate the o-rings on all four drive fittings Connect and tighten the lower drive hoses, then connect the upper hoses and tighten 3 Motor Seal Kit Installation Remove the tire/wheel assembly and motor cover Clean the area around the drive motor and fittings Mark the motor hoses for correct installation Disconnect the case drain hose and drive hoses from the motor After disconnecting fittings, cap and plug open hoses and ports to prevent contamination Remove the twelve mounting bolts and remove the first motor section and place it on a work bench NOTE: Before removing all of the bolts, install two studs (with screw driver slots on the ends) into mounting bolt holes on each side of the motor These will keep the piston ring and piston/roller section in place and assist installation Make the studs by cutting the heads off of two M12X1 75 metric bolts that are at least 100 mm long NOTE: When installing new seals, ensure all parts are clean Lubricate the seals with hydraulic fluid before installing them For this field modification, remove and replace only the seals described below Remove the plug from the end of the housing Remove the o-ring from the plug and install the new o-ring onto the plug Use a brass drift through the end plug hole and remove the distributor from the housing 4 ,-­ Remove the four seals from the housing Note the location and sizes of the seals / Install the new seals in place of the old seals Be careful when installing these seals to minimize seal distortion Lightly smear grease over these seals to keep them in place Cross section view of motor housing showing seal location Align the distributor hole with the stop pin in the housing Ensure the springs remain in the distributor Install the distributor into the housing When the distributor is aligned correctly, the distributor can be depressed slightly against the springs Install the plug in the end housing Tighten to 60-65 ft-lbs (85 Nm) torque Install the housing to the drive motor Install several bolts, then remove the two alignment studs and install the remaining bolts but do not tighten the bolts Position the motor housing and outer piston assembly ring so it is centered with the motor carrier Use a star pattern and tighten the mounting bolts to 90 ft-lbs (125 Nm) torque When tightening the mounting bolts check and ensure the motor housing , outer piston assembly ring and motor carrier are centered Repeat for the other motor 5 Install new a-rings on the drive motor fittings and lubricate Fill both motor cases with clean hydraulic fluid through the motor case drain port as full as you can Connect the motor case drain hoses IMPORTANT: Before operating the hydrostatic motor, it must be full of oil Machine Start-Up Add new clean· hydraulic fluid to the proper level in the reservoir Lower the operator cab and tighten the front hold down nuts to 45 ft-lbs (60 Nm) torque Refer to the Operation & Maintenance Manual To ensure the motors are full of oil, disconnect the drain hose to one motor Set the parking brake and start the engine at low idle Stroke the steering lever slightly on the side with the disconnected motor drain hose Stop the engine when oil comes out of the case drain port Connect the case drain hose Repeat for the other motor Install the motor covers and tire/wheel assemblies Remove the jack stands Operate the loader Check for proper operation and check for leaks A WARNING Hydraulic fluid under pressure can penetrate skin or eyes, causing serious injury or death Fluid leaks under pressure may not be visible Use a piece of cardboard or wood to find leaks Do not use your bare hand Wear safety goggles If fluid enters skin or eyes, get immediate medical attention from a physician familiar with this injury  for the cost of the shunt hose kit, two motor seal kits, bolts and a-rings as described in this letter Warranty compensation for five and one half (5-1/2) hours labor to install these improvements will also be given One (1) additional hour is allowed for travel time for retailed machines When filing warranty claims electronically use service code 08R79 This offer expires December 2, 1997 6 DIRECT TO: / / MELROE / bobcat DATE: 11 November 1996 MODEL: 12 AUGER ATTACHMENT SUBJECT: SERIAL NUMBER IDENTIFICATION Melroe Company has determined that an incorrect serial number prefix was used in some model 12 auger attachments Model 12 augers with incorrect numbers were 4i7506200 through 4i7506676 These units should have had serial numbers 47506200 through 47506676 Be aware of this serial number discrepancy for your warranty and customer records New serial number plates will not be sent to dealers Serial numbers 437506199 and below are Correct Serial numbers 427506200 through 427506676 are incorrect Use 4375xxxxx Serial numbers 437506677 and above are Correct AUGERSN DOC Printed in USA DIRECT TO: / / MELROE / INGERSOLLAND bobcat DATE: 15October1996 MODEL: 320 EXCAVATOR (S/N 511720001 -511725102) SUBJECT: BOOM CYLINDER HOSE PINCH POINT Melroe Company has determined that the boom cylinder hoses can compress against the boom during digging at maximum depth This affects only model 320 excavators with serial numbers listed above The swing post has been modified to provide additional clearance  on machines serial number 511725103 and above If you are replacing a boom cylinder hose, inspect the hose in the area shown in the photo If the hose requires replacement because of wear in this area, perform the following swing post modification This modification will provide additional clearance for the boom cylinder hoses when the boom is at maximum digging depth Swing post modification: Refer to the model 320 excavator Service Manual for boom removal and replacement Remove the boom from the swing post Continued on the reverse side 320HOSE 00C Printed in USA 1 2 DIRECT TO: / MELROE 	Pi / 	bobcat / DATE: 11October1996 MODEL: 331, 325, 231 (12,000 SERIES) AND 225 EXCAVATORS SUBJECT: NEW BOOM CYLINDER GUARD A new design boom cylinder guard is installed on current production model 331  	and 325 excavators The new design provides improved service life and greater boom cylinder protection The new guard can be installed on earlier machines This letter provides information for installing the new guard in place of the old guard For model 331 and 231 (12,000) excavators, order kit (P/N 6800329) For model 325 and 225 excavators, order kit (P/N 6800328) The kits are available from Melroe Parts Sales Each kit contains one each of the following parts: Kit No Kit No Description 6800329 6800328 Spacer 6800138 6800137 Cap Screw 59CM-1245 59CM-1235 Guard 6596493 6596469 Guide 6628788 6628788 Washer 15EM-120 None UUARDJXX: Printed in USA 1 Put the bucket on the floor Stop the engine Move the hydraulic control to release the hydraulic pressure Fasten a chain hoist to the boom Remove the existing boom cylinder guard Discard the mounting bolt, washer and spacer Grind the weld from the existing guard guide and remove the guide from the boom cylinder With the grinder, carefully remove the remaining weld from the cylinder body Do not remove cylinder material Locate the new guide onto the underside of the boom cylinder Measure down from the end of the cylinder end cap The top edge of the new guide should be 750" (190 mm) from the end of the cylinder end cap on model 325 and 225 excavators The top of the new guide should be 1650" (419 mm) from the end of the cylinder end cap on model 331 and 231 excavators Locate the guide onto the cylinder in the correct location and trace around the guide Grind the paint from the boom cylinder on the outer edges of where the guide will be located Position the guide onto the bottom of the boom cylinder the correct distance from the end cap Clamp the guide to the cylinder (see photo) The guide must be perpendicular to the ground A long straight edge held between the center of the cylinder rod end and the center of the base end can be used to ensure the guide is centered on the cylinder barrel 2 ( Back the cylinder end cap out three turns using gland wrench tool MEL 1075 This will protect the seals from heat during welding Weld the guide to the boom cylinder Apply a 1 /8" fillet weld 3/4" long onto both sides of the guide After the cylinder cools, tighten the cylinder end cap onto the cylinder barrel Clean the weld and paint the new guide Slide the new guard over the guide Attach the front of the guard to the eye end of the boom cylinder using the front guard spacer and the cap screw NOTE: On models 331 & 231 install washer (P/N 1 SEM-120) under the head of the cap screw NOTE: Before installing the cap screw, thoroughly clean the mounting hole with a bottoming tap and flush clean with solvent Tighten the cap screw to 50 ft-Lbs (70 Nm) torque Remove the hoist Fully raise the boom and ensure the slot in the guard does not bottom against the guide  No warranty is implied 3 DIRECT TO: / / MELROE / n 	bobcat DATE: 	9October1996 MODEL: 	320 (SIN 511720001 -511724731) 325 (S/N 514011001 -514013251) 331 (S/N 512911001 -512913287, 13292 & 13293) SUBJECT: STARTER MOTOR GROUND CABLE A ground cable has been added to all current production model 320, 325 and 331 !' 	excavators The ground cable provides improved electrical ground for starter operation If you encounter poor starter performance or starter failure due to inadequate electrical ground in machines with serial numbers listed above, we recommend installing the new ground cable Order ground cable (P/N 6565170) from Melroe Parts Sales NOTE: For models 325 and 331 , also order one washer (P/N 1EM-100) and one self tapping screw (P/N 26GM-10020) MODEL 320 Remove the lower starter mounting bolt and reinstall with one end of the ground cable under the bolt Install the other end with the engine ground that connects to the frame Use the existing bolt Continued on the reverse side EXCGRNOOOC Printed in USA 1 MODEL 325 Remove the lower starter mounting bolt ( 1 ), and reinstall with one end of the ground cable under the bolt Install the other end to the hole in the frame ( 2 ) using a washer (P/N 1EM-100) and self tapping screw (26GM-10020) Install the washer between the frame and the cable MODEL 331 Remove the lower starter mounting bolt ( 1 ), and reinstall with one end of the ground cable under the bolt Install the other end to the frame using a washer (P/N 1EM-100) and self tapping screw (26GM-10020) Install the washer between the frame and the cable NOTE: Some earlier model 325 and 331 excavators may not have a hole in the frame for the ground cable A ground cable can be added between the lower starter mounting bolt and a suitable location on the excavator frame  Normal warranty policy applies 2 DIRECT TO: / / MELROE / - bobcat DATE: 7October1996 MODEL: 331 S/N 51192001 & ABOVE 331 S/N 512911001 -512912165 231 ALL SUBJECT: NEW BOOM CYLINDER BASE END PIN A new design boom cylinder mounting pin is installed in current production model 331 excavators serial number 512911001 and above This design provides improved mounting with a welded tab to prevent pin rotation If you are servicing a model 331 or 231 (12,000 series) excavator with an old pin design (see serial numbers above) for a broken pin or pin mounting bolt, we recommend installing the new design pin Continued 331 PINDOC Printed in USA 1 You will need the following parts to convert to the new pin: P/N DESCRIPTION QTY REF 6534154 Snap Ring 1 A 6534111 Thick Washer 1 B 6535313 Thin Washer 1 C 6597200 Boom Pivot Pin 1 D 6586327 Bushing 1 E 1CM-1245 Bolt 1 F Lower the bucket to the floor Stop the engine and engage the swing lock pin Move the hydraulic control joystick to release the hydraulic pressure to the boom cylinder Fasten a chain hoist to the boom Remove the retaining bolt O and nut Support the base of the boom cylinder and remove the cylinder base end pin e NOTE: On some machines it may be difficult to drive the pin out The retaining bolt may be broken or the pin may be rusted in place In these cases the pin can be removed in a hydraulic press Cut through the pin on each side of the boom cylinder using a cutting torch Protect or remove the hydraulic hoses and tubelines from the area to prevent fires Remove the boom cylinder and attempt to remove each end of the pin If the pin ends still cannot be removed, remove the swing frame assembly from the excavator (refer to the Service Manual for removal) With the swing frame removed, the remaining pin can be removed in a hydraulic press When using the hydraulic press, support the swing frame casting at the pin to prevent damage to the swing frame 2 Install the new boom cylinder pin from the left side of the machine Rotate the tab on !-- the end of the pin toward the rear of the machine NOTE: On 11,000 series model 231 machines, install the pin from the right side Install the thin white washer (P/N 6535313) then the thick washer (P/N 6534111) on the end of the pin The white washer is used as a spacer On some machines there may not be space for the white washer If there is not room, do not install the white washer Install the snap ring (P/N 6534154) onto the end of the pin Drill a 13/32" (105 mm) diameter hole 1 3/4" (445 mm) deep in the center of the tabs Tap 12 mm X 1 75 threads into the hole Install the bushing and bolt Put Loctite 242 or equivalent on the bolt threads before installation Remove the chain hoist from the boom 3 DIRECT TO: MELROE 00 00 00 FIELD MODIFICATION DATE: 3October1996 MODEL: 8709 BACKHOE WITH MODEL 873 LOADER SUBJECT: NEW LOW PROFILE BACKHOE MOUNTS New backhoe mounts are now supplied with the 8709 backhoe mounting kit (P/N 6596588) The new mounts are lower profile to provide clearance for the cab door on machines equipped with an optional cab enclosure If you receive a complaint that the cab door contacts the backhoe mounting hooks, we recommend installing the new low profile mounts New mounts are available from Melroe Parts Sales P/N Description 6712276 Left Side Mount 6712275 Right Side Mount When installing the new mounts, install the short bolts in the outside holes and the long bolts in the inside holes Tighten the nuts to 95 ft-lbs (130 Nm) torque  for the cost of the new low profile mounts and one half (1/2) hour labor to install the mounts One (1) additional hour is allowed for travel time for retailed machines This offer expires on October 3, 1997 When filing warranty claims electronically use service code 01 R69 MOUNTSDOC Printed in USA DIRECT TO: MELROE 00 00 00 FIELD MODIFICATION DATE: 	16September1996 MODEL: 	653 EXPORT, 751, 753, 763 & n3 LOADERS WITH REAR AUXILIARY HYDRAULICS KIT OR ATTACHMENT ELECTRICAL CONTROL KIT SUBJECT: NEW AUXILIARY CONTROL MODULE (P/N 6669529) Melroe Company has determined that new auxiliary control module (P/N 6669529) must be installed in machines with serial numbers listed below if they are equipped with a dealer  	installed rear auxiliary hydraulics kit or attachment electrical control kit The new module prevents interrupted operation of the front and rear auxiliary hydraulics during operation Affected machine models and serial numbers: Domestic Loaders: 751 514713054-514713170 753 512727535 -512727762 (except 27723) 763 512218994 -512219181 (except 19054) 773 509639994 -509640097 (except 40030 & 40093) Continued on the reverse side European Loaders: 653 export 514811117 -514811141 751 514911467 -514911485 7530 508694545 -508694573 763 512440660 -512440666 773 509616509 -509616515 AUXCNTUlOOC Printed in USA 1 When installing the following kits in the serial number machines listed on page 1, also order and install new auxiliary control module (P/N 6669529) from Melroe Parts Sales: Kit P/N 6711676 6711678 6710436 6710437 6710440 6710441 6709228 Description Rear Hydraulic Rear Hydraulic Rear Hydraulic Rear Hydraulic Rear Hydraulic Rear Hydraulic Attachment Electrical Control Models 653 export, 751 & 753 751 European, 753 European 763 763 European 773 773 European ALL The auxiliary control module is located under the cab on the side of the left fender Raise the operator cab Refer to the Operation and Maintenance Manual Install the new auxiliary control module in place of the existing module Lower the operator cab and tighten the front hold down nuts Refer to the Operation and Maintenance Manual  for the cost of the new auxiliary control module (P/N 6669529) when installing the above listed kits in machines with serial numbers as shown in this Service Letter If you have already installed an above listed kit in a machine with a serial number listed in this Service Letter, warranty compensation for one half (1/2) hour to install the new auxiliary control module will be given One (1) additional hour is allowed for travel time for retailed machines When filing warranty claims electronically use service code 07R78 2 DIRECT TO: MELROE !XI !XI !XI DATE: 10 September 1996 MODEL: COMBINATION BUCKET ATTACHMENT (S/N &Below) SUBJECT: RECESS FOR DIRT AT CYLINDERS A recess has been added to current production A combination bucket attachments The recess is between each cylinder base end and the back of the bucket The recess allows debris to escape This helps prevent debris from compacting between the cylinder and the back of the bucket This extends the service life of the cylinders Earlier combination buckets Serial Numbered and Below ,- 	can be modified to provide a recess for debris to escape Use the following procedure to modify the attachment With the attachment removed from the loader and the bucket in the closed position, remove the four cylinder cover mounting bolts (Item 1) [A] Remove the hydraulic cylinder (Item 1) [BJ from the B attachment Put plugs and caps on the open ports to prevent dirt from entering the hydraulic system SLCOMBKT Printed in USA A WARNING Eye and body protection is required when welding or grinding Wear approved goggles, helmet and clothing Failure to wear eye and body protection can result in serious injury W-2009-1285 Remove the material from the lower, back of the bucket, directly behind the base end of the cylinder The piece removed will be L-shaped about 3-1/2 inches (90 mm) wide (Item 1) [A] Be careful not to cut into the back of the bucket (ltem2) [A] Repeat for the other side of the bucket Grind the cut areas smooth Cut two triangle-shaped pieces from 3/16 inch (5 mm) thick steel [B] Weld one triangle piece (Item 3) [A] to the inside cylinder mount (between the two cylinder mounts) Weld all the way around the triangle The triangle will cover the end of the cavity exposed by cutting the L-shaped piece from the bucket Repeat for the other side of bucket Clean and prepare the surfaces for paint Paint the surf aces Install the cylinders and cylinder covers \  ,} DIRECT TO: MELROE 00 00 00 DATE: 22 August 1996 MODEL: ALL LOADERS WITH GAS SPRING ASSISTED SEAT BAR SUBJECT: GUSSET FOR SEAT BAR The Seat Bar may become bent so that one side of the Seat Bar hits the side screens of the cab This condition can be corrected by straightening the Seat Bar and installing a gusset on the gas spring side of the Seat Bar (Item 1) [A] Order the gusset (P/N 6712497) from Melroe Parts Operation in Chicago or make your own gusset as shown [B] SBGUSSETDOC Printed in USA 1 Make a tool from a wood block as shown [A) ApproxA 4" (100mm) Remove the Operator's Handbook from the pocket in the cab Install the tool between the Seat Bar and the rear of the cab [B] Put both hands on the center padded area of the Seat Bar Then, push down on the Seat Bar until the tool is free Disconnect the negative cable from the battery and disconnect the wires from the alternator Cover the seat and other flammable areas with a fireproof material Install the gusset on the inside of the bend on the gas spring side of the Seat Bar [C) Weld the inside of the gusset using a 1/8 inch weld bead Be careful not to burn through the Seat Bar tube Reconnect the battery cable and the alternator wires Install the Operator Handbook into the pocket  only Normal warranty policy applies  DIRECT TO: MELROE / / 	bobcat / Service letter DATE: 	20 August 1996 MODEL: 	320 EXCAVATOR (S/N 511720001 -511724186) 325 EXCAVATOR (S/N 511820001 -511821184) 331 EXCAVATOR (S/N 511920001 -511920461) 331 EXCAVATOR (S/N 512911001 -512912239) SUBJECT: NEW CASE DRAIN LINE FILTER A new case drain line filter is now installed in current production model 300 series excavators and the 100 mesh screen that was located in the drain block is now removed The new case drain line filter has an increased filter area that reduces case drain line back pressure Reduced case drain line back pressure extends the service life of the swing motor shaft seal and travel motor seals If servicing machines with the old style drain screen because the screen is plugged, we recommend removing the screen from the drain block and installing the new in-line case drain filter This procedure takes approximately one half to one hour to perform depending on model The following parts are required to install the new case drain line filter: P/N DescriRtion Qt}! Ref 15K-5 Adapter fitting 1 A 6667552 Filter 1 B 6558510 Elbow 1 c 6586582 Hose (320 Only) 1 A new service schedule or maintenance decal is also required Order the correct decal for each machine below: Model S/N 	Decal P/N 320 511720001 -511724186 325 511820001 -511821184 · 331 511920001 -511920461 331 512911001 -512912239 EXCFILTDOC 6628904 6801201 6801201 6628906 Printed in USA 1 NEW CASE DRAIN FILTER INSTALLATION MODEL 331 SHOWN The procedure is the same for other models Remove the case drain hose from the elbow fitting at the side of the hydraulic reservoir Remove the elbow fitting from the reservoir and discard NOTE: On some machines the elbow fitting does not need to be removed If the original elbow fitting is long enough to accept the filter, do not remove it Install the new elbow fitting (if required) in the reservoir Tighten the jam nut Install the adapter fitting into the inlet end of the drain filter Install the outlet end of the drain filter onto the elbow at the hydraulic reservoir NOTE: The drain filter must be installed with the end marked "OUT" toward the hydraulic reservoir (elbow fitting) Connect the hose to the drain filter Model 320: Install new drain hose (P/N 6586582) in place of the existing hose We recommend cleaning this filter every 500 hours of operation REMOVE THE 100 MESH SCREEN FROM THE DRAIN BLOCK The drain block is located under the floor panel at the operators' feet (model 325 and 331) The screen is under the bottom fitting 2 The drain block is located under the machine just forward of the engine on the model 320 excavator See photo showing bottom view of machine The screen is under the fitting facing the rear of the machine Remove the fitting from the drain block, remove and discard the 1 00 mesh screen (shown with drain block removed for clarity) Replace the fitting Install the new service schedule decal over the original decal If the decal is a new drain filter maintenance decal, install it below the service schedule decal  Normal warranty policy applies 3 DIRECT TO: MELROE 00 00 00 FIELD MODIFICATION DATE: 8August1996 MODEL: 863 WITH REAR STABILIZER KIT (P/N 6711748) SUBJECT: NEW GREASABLE LIFTARM PIVOT PIN (P/N 6713054) A new greasable lift arm pivot pin (P/N 6713054) has been added to the 863 rear stabilizer kit (P/N 67117 48) This pin provides a method for lubricating the lift arm pivot The old pin did not provide a method for greasing the lift arm pivot Kits now contain the new greasable pin If you have installed rear stabilizer kit (P/N 67117 48) on a model 863 loader and it did not include greasable lift arm pivot pins, order two new pins (P/N 6713054) and grease fittings (P/N 1 OH-35) from Mel roe Parts Sales Install the new pins in place of the existing pins that came with the kit Install the grease fittings into the new pins Grease the pins  for the cost of the new pins and grease fittings One half (1/2) hour labor to install the new pins will be provided for machines which have had the kit already installed One (1) additional hour is allowed for travel time for retailed machines This offer expires on 8 August 1997 When filing warranty claims use service code 08R73 GREASEPNDOC Printed in USA DIRECT TO: / / MELROE / bobcat DATE: 19 July 1996 MODEL: 653 EXPORT, 751, 753, 763 AND 773 SUBJECT: NEW SPRING LOADED DRIVE BELT IDLER ASSEMBLY NOTE: This Service Letter replaces Service Letter dated 21 September 1995 Additional models are now affected Discard Service Letter dated 21 September 1995 ,,,,,----- A new spring loaded drive belt idler is now installed on model 653 export, 751 , 753, 763 and 773 loaders The new idler assembly is spring loaded to maintain proper drive belt tension The idler has a visual gauge to indicate proper belt tension With this new design, a spring scale and special bar are no longer requred for adjusting belt tension A new decal is located inside the tailgate and provides the adjustment procedure This procedure will be added to the service manuals  Continued on the reverse side SPRIDLRBDOC Printed in USA 1 SPRING LOADED IDLER ADJUSTING PROCEDURE IMPORTANT I The belt tension is maintained by a spring The working range is Indicated by a pointer (Item 1 ) DO NOT use the specifications or the tool PIN MEL 1405 which was used for the previous fixed idler pulley The tool PIN MEL 1405 can be used as a prybar to reset the Idler tension spring 1 The pointer will be at the 1 o'clock position when the idler is not under spring tension Push the idler assembly against the belt (use a prybar) 2 The pointer will be at the 3 o'clock position when the idler stop is bottomed out From the 3 o'clock position, raise the idler slighty so that the idler is operating on the spring tension Tighten the mounting bolt (Item 2) to 25-28 ftlbs (34-38 Nm) torque IMPORTANT I DO NOT load the idler against its travel stop in the 3 o'clock position 3 Run the engine for a few minutes Stop the engine and recheck the pointer position Readjust if necessary 4 After the idler has been in service, readjust when the pointer reaches the 1 o'clock position 5 See Service Manual for more detailed information SW 95 6709030 IMPORTANT: The decal contains an important note to NOT load the idler against its travel stop in the 3 o'clock position This would prevent the spring from performing its intended function and will reduce the service life or cause a failure of the idler assembly and drive belt The new spring loaded idler assembly is the service replacement for the old fixed idler assembly If idler assembly replacement is required, order and install the new spring loaded idler assembly and a new service decal to be installed in the tailgate The following is a list of parts required to install the new spring loaded idler assembly in place of the old fixed idler assembly: Model 753, 763 and 773 Spring Loaded Idler Assembly (P/N 6711698) Service Decal (P/N 6709030) Model 653 export and 751 Spring Loaded Idler Assembly (P/N 6711698) Service Decal (P/N 6711905) Threaded Rod (P/N 6708771)  Normal warranty policy applies "'- / 2 DIRECT TO: BOBCAT® /  / / D D D D DATE: 17 July 1996 SUBJECT: REPLACEMENT SPOOLS FOR MELROE CONTROL VALVES This Service Letter replaces Service Letter dated 20 February 1995 The warranty policy has been revised and part numbers are referred to the parts book Replacement spools are now available for Melroe manufactured hydraulic control valves Replacement spools may be installed in place of damaged spools provided the valve body and spool bore are in serviceable condition For example a spool with wear or pitting in the seal area NOTE: Melroe warranty policy is revised If the hydraulic control valve is still under warranty and a spool requires replacement, replace the individual spool following the guidelines in this letter When Melroe hydraulic valves are Paint manufactured, spools are selected for or proper fit Currently, three sizes are used Number The size difference between spools is approximately twenty five millionths mtQl/ (000025") Spools have been identified by a small paint spot on the end of the spool (linkage end) This paint MC-1606 identification system has been in use since November 1992 Continued on the reverse side Spools2doc Printed in USA For these valves the color coding can be used for replacement spool selection These are valves with an identification number 22,000 and above For spool replacement in valves with an identification n'umber 19,999 and below, the color code on the end of the spool should not be relied upon for spool replacement For these, follow the procedure for spool selection which follows If the color can not be identified, use the spool selection procedure We recommend dealers stock all three sizes to allow for selection during the spool selection procedure Current production spools are now stamped with a number on the end of the spool This number will indicate the correct size replacement spool and provides a more positive identification than the paint method Refer to the parts book for replacement spool part numbers First identify the type of valve installed in the machine For some models there are two styles, short spool (current style) and long spool (old style) The short spools are approximately 9 1 /4" long and the long spools are approximately 9 3/4" long Determine the correct diameter of the replacement spool by the color or number on the end of the spool Color No Size (Dia) Red 1 Large Green 2 Med Black 3 Small Note: Color and size identification is for current production only, valves with identification number 22,000 and above If the color or number can not be identified, use the following spool selection procedure The auxiliary spool is available in one size only Spool Selection Procedure The cause for spool damage must be determined and corrected Any contamination must be completely removed from the system Use a small light and carefully inspect the bore for scratches, scores, or cracks Clean the replacement spool and inspect the spool for any damage from improper handling or manufacture Check for nicks or burrs Inspect the sealing area for scratches which would cause leaks With no spool seals in place, lubricate the spool and bore Carefully install the spool in its bore Place the spool in the neutral position Rotate the spool one turn and check for freedom of movement Move the spool 1 /2" either side of neutral and check for smooth movement The spool may fit snug but must not require excessive force to move A good test to determine if the spool is too tight is to hold the valve side ways over a protective pad Raise the spool almost out of its bore and release The weight of the spool alone must allow the spool to drop to the pad If the spool will not drop through, it must not be used It is either too tight, has damage, or the valve bore has damage If the spool is too tight try the next smallest spool 3 DIRECT TO: MELROE 00 00 00 FIELD MODIFICATION DATE: 17 June 1996 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICS™) SUBJECT: SEAT RAIL COVER KIT (PIN 6712184) Seat rail covers are now installed under the loader's seat rails on all machines equipped with the BIGS The covers provide an enclosure for the space under both seat rails and permits unrestricted up and down movement of the seat This is necessary for activation of · the BIGS seat sensor The covers will minimize required maintenance of cleaning dirt, debris or other objects underneath the seat rails as explained in the Operation and Maintenance Manual NOTE: Adjustment of sliding the seat forwards or backwards is not affected Cont\nued RJAM5DOC Printed in USA 1 A seat rail cover kit (P/N 6712184) is available for earlier manufactured machines If the loader is used in an application where there has been a need for frequent cleaning underneath the seat rails, the seat rail covers will reduce the frequency of required maintenance Order kit (P/N 6712184) from Melroe Parts Sales Installation instructions (P/N 6724800) are also included This service letter does not affect machines with: SIDE PIVOT SEAT KITS (P/N 6708913) or OPTIONAL GRAMMER SUSPENSION SEATS  for the cost of the kit and one (1) hour labor for installation One (1) additional hour is allowed for travel time for retailed machines When filing warranty claims electronically use service code 01 R64 DIRECT TO: / MELROE / 	 bobcat / DATE: 13 May 1996 MODEL: 2560 HYDRAULIC BREAKER SUBJECT: QUICK COUPLERS, HOSE AND TUBELINE SERVICE Hydraulic pressure pulsations in the 2560 hydraulic breaker can cause reduced service life of hydraulic tubelines, hoses and quick couplers in the circuit If you are servicing hydraulic tubelines, hoses or quick couplers in a 2560 hydraulic breaker application, be aware of the following· items that can contribute to increased hydraulic pressure pulsations: 1 	The proper size hoses must be used: The hoses from the breaker attachment to the two position frame must be 3/4" ID The correct hoses are (P/N 6705737) If smaller ID hoses have been installed, remove them and install the correct hoses The hoses from the two position frame to the quick couplers were increased to 5/8" ID from 1/2" ID These hoses are (P/N 6710460) Changing to 5/8" ID hoses will reduce hydraulic pressure pulsations Continued :!560BSADOC Printed in USA 1 With· excavators, the hoses from the breaker attachment to the quick couplers were changed to 5/8" ID from 1/2" when flush face quick couplers went on line These hoses are (P/N 6711709) Changing to 5/8" ID hoses will reduce hydraulic pressure pulsations 2 	 Hydraulic breaker applications reduce the service life of quick couplers Regular inspection and replacement is required If the couplers are damaged they may restrict hydraulic oil flow and increase pressure pulsations The new flush face couplers [female (P/N 6667807) and male (P/N 6667808)] are available from Melroe Parts Sales and will provide extended service life, however, regular inspection and replacement is still required Refer to BTI 302 for converting to the new flush face quick couplers on loaders Refer to BTI E-045 for converting to the new flush face quick couplers on excavators 3 	 Check the nitrogen chamber pressure in the breaker attachment and charge if necessary The correct pressure is 350 psi at room temperature Refer to the breaker Operation or Service manual for the procedure 4 	 Check and ensure correct auxiliaryhydraulic oil flow and relief pressure at the loader or excavator quick couplers Refer to the machines Service Manual or Tech Service Guide for flow and pressure specifications Continued 2 5 If the correct hose sizes are installed  Normal warranty policy applies and excess pressure pulsations are still observed, the valve seals in the hydraulic breaker need to be replaced Refer to the Hydraulic Breaker Service Manual (P/N 6720280) One each of the following is· required to reseal the valve Order individually from Melroe Parts Sales P/N Description ·Ref 6663943 Seal A 79K-4 0-ring B 6663940 Seal c 6663941 Seal D 6663936 Back-up Ring E 6663935 Seal F 6663933 Seal G 6663934 Back-up Ring H 6663932 Back-up Ring I 6663931 Seal J 6663930 Back-up Ring K 6663929 Seal L Whenever the valve is removed for inspection, new seals must be installed Often seal failure can not be detected by visual inspection Visually inspect the spool and valve for damage Replace if damaged 6P OA ' 9 ' \ 90 \ @ I oc \ 8 oO ' bE FO6G HO61 JO ' K 0 LO t L   e--­ -:::t    3 · DIRECT TO: ·, / / MELROE / DATE: 10May1996 MODEL: 2500 AND 3500 HYDRAULIC BREAKERS SUBJECT: SEAL SERVICE PROCEDURE NOTE: This Service Letter replaces Service Letter dated 19 April 1994 Revised for new kit part numbers and seal identification New seals are installed in model 2500 and 3500 hydraulic breakers The new seals are a Disogrin brand seal The Disogrin seals provide extended seal life Cross hatches are added to the hammer piston to allow the Disogrin seals to be used Important seal installation procedures are provided below The hydraulic breaker service manual (P/N 6720280) will be revised to include installation of the new seals Follow the hydraulic breaker service manual for general service procedures The seals affected are the lower bearing inner seal 0 and the lower housing wiper seal e (see diagram) Original hammer pistons were polished for use with earlier seals When using the Disogrin seals the hammer pistons are cross hatched in the Cross Hatch sealing area The cross hatch pattern helps trap oil to lubricate the Disogrin seals Lower Housing The Disogrin seals and cross hatched hammer pistons are installed at the following serial numbers: 2500 hydraulic breaker (S/N 896706461 & above) and (S/N 705200199 & above) 3500 hydraulic breaker (S/N 897200816 & above) and (S/N 705400144 & above) All units below these serial numbers used poly-pak seals and polished hammer pistons OISOGAINDOC Printed in USA 1 2500 and 3500 hammer piston seal installation procedure: NOTE: The seal kits (P/N 6666550) for 2500 and (P/N 6666551) for 3500 include poly­pak and Disogrin seals We recommend installing the Disogrin seals as described below The approximate seal lD is provided to help identify the correct seal Do not measure on the seal lip Inspect the hammer piston seal area for a cross hatch pattern If there is no cross hatch pattern (polished piston) apply a new cross hatch pattern If there is a cross hatch pattern and it is partially worn smooth, apply a new cross hatch pattern To apply a cross hatch pattern, place the hammer piston on a work bench and hold it in an upright position Use Scotch Brite or emery cloth and move it up and down 0 Hammer Piston Cross Hatch This Aea Only in the area shown while rotating the hammer This will produce very fine surface scratching in a cross hatched pattern 2500 Hydraulic Breaker: Lower housing wiper seal: Discard the original (orange, black or cream) colored seal Install the new 211 O" orange (Disogrin) seal Lower bearing inner seal: Discard the original (yellow or cream) seal Install the new 2140" cream (Disogrin) seal in its place Note: The yellow seal is for hammer pistons that are not cross hatched 3500 Hydraulic Breaker Only: Lower housing wiper seal: Discard the original (gray, spacer and black, orange or cream) colored seal Install the new 2050" orange (Disogrin) seal Lower bearing inner seal: Discard the original (cream or gray) seal Install the 2020" cream colored (Disogrin) seal in its place NOTE: Only cross hatched hammer pistons may be used with the Disogrin seals and only polished hammer pistons may be used with the poly-pak seals Inter-mixing of these parts will result in premature seal failure ·· /'· 3 DIRECT TO: / / MELROE / INGERSOLL-AAND bobcat' Service letter DATE: 6May1996 MODEL: 2560 HYDRAULIC BREAKER SUBJECT: SERIAL NUMBER IDENTIFICATION Melroe Company has determined that an extra numeral has been added to the serial number of some model 2560 hydraulic breaker attachments Normally a nine digit serial number is used The serial numbers on 2560 breakers through serial number 617900999 are correct The next 2560 breaker built had an extra zero added in the middle of the serial number Its serial number is 61790Q1000 (extra zero underlined) This continued through serial number 61790Q2969 Machines serial number 617902970 and above have been corrected Be aware of this serial number discrepancy for your warranty and customer records 617900999 and below Correct 61790Q1000 through 61790Q2969 Additional zero 617902970 and above Correct NOTE: Some of the serial number plates in this group may have had the extra zero ground off, thus making them appear correct 2560SNADOC Printed in USA DIRECT TO: / MELROE / bobcat / DATE: 18 April 1996 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICSTM) SUBJECT: TRACTION LOCK SOLENOID SERVICE REPLACEMENT Loaders equipped with SICS use an electric solenoid to release the traction lock A new style solenoid with associated parts is now installed in current production loaders To ensure proper function of the traction lock solenoid do not mix old parts with new parts When stock of the old solenoids is depleted, they will no longer be available The following information describes the new and old solenoids, and the parts that must be used with each -The traction lock solenoid is located on top of the chain case under the operator cab (853 shown) Refer to the Service Manual for removal and replacement NEW STYLE TRACTION LOCK SOLENOID FOR ALL MODELS (P/N 6667992) The new style traction lock solenoid contains the following parts These parts must be used with the new solenoid Do not substitute any of these parts with parts used with the old style solenoid Solenoid (with sleeve) A Spring (green) B Spring retainer cup C Plunger (3500") D Continued on the reverse side !"'"'- SOLENOIDDOC: Printed in USA 1 OLD STYLE SOLENOID (P/N 6662882) and (P/N 6666304) (model 953 loaders) The old style traction lock solenoid contains the following parts These parts must be used with the old solenoid Do not substitute any of these parts with parts used with the new style solenoid Solenoid (without sleeve) A Spring (red)B Plunger (3400")C PART IDENTIFICATION The new style solenoid can be identified by an extended sleeve The old style solenoid does not have this sleeve The new style plunger can be identified by its length of 3500 inches The old style plunger is shorter at 3400 inches The new style spring is lighter (easier to compress) than the old style spring The new style spring can be identified by a patch of green paint on one end The old style has a patch of red paint on one end The new style solenoid uses an additional spring retainer cup It is located on the end of the spring (see photo page 1) The old style solenoid did not use this retainer 2 DIRECT TO: v' MELROE v' bobcat' v' DATE: 14 March 1996 SUBJECT: NEW BOSS DIAGNOSTIC TOOL CARTRIDGE MEL 1445 For the first time both initialization and diagnostic functions are combined into one cartridge The new MEL 1445 cartridge supersedes both the MEL 1400-7 diagnostic cartridge and the MEL 1400-14 initialization cartridge This new cartridge is required to initialize any current production "BOSS' module including replacement modules It also provides enhanced diagnostics of all current production "BOSS" modules as well as all earlier units NOTE: The old MEL 1400-7 diagnostic cartridge is still required to program the older "BOSS" backup unit (P/N 6661110) If you own or may acquire this unit, do not discard your present MEL 1400-7 diagnostic cartridge The (P/N 6661110) is not the current production "BOSS" backup unit and is the only application which requires the MEL 1400-7 cartridge Should you need to replace your current MEL 1400-7 diagnostic cartridge for use with (P/N 6661110) "BOSS" backup unit, it will be necessary to order MEL 1400-7A The new cartridge is available from Service Tools Division 655 Eisenhower Drive Owatonna, MN 55060 1-800-533-0492 mell 44Sdoc Printed in USA DIRECT TO: / MELROE / / DATE: 12 March 1996 MODEL: 873 (SIN 514111001 -514111231) 873 EUROPEAN (S/N 514211001 -514211039) SUBJECT: BRAKE DISC NOISE A new design brake disc is installed in current production model 873 loaders The new design is a fixed disc design which eliminates the brake disc guide This significantly reduces noise from the brake discs contacting the guide A kit (P/N 6711195) is now available from Melroe Parts Sales This kit installs on earlier machines (see serial numbers listed above) and modifies them to the fixed disc design If you are servicing a machine in this serial number range because of brake disc noise, or what appears to be chain noise, we recommend installing this kit Complete installation instructions (P/N 6724781) are included 87JFIXEDDOC Printed in USA DIRECT TO: / MELROE / / DATE: 7 March 1996 MODEL: 751 AND 653 EXPORT SUBJECT: RECOMMENDED ENGINE SERVICE TOOLS The following tools are recommended to have available in the shop for service of the Peugeot XUD9 engine used in the model 751 and 653 Export loaders MEL1474 Peugeot Engine Tool Kit (all listed below): MEL 1475 Valve Seal Drift MEL 1476 Valve Seal Removal Pliers MEL 1477 Camshaft Seal Installer MEL 1478 Support Rod/Dial Gauge Holder MEL 1479 Crankshaft Seal Installer (Front) MEL 1480 Main Bearing Joint Installer MEL1481 Crankshaft Seal Installer (Rear) MEL 1482 Dial Gauge Support MEL 1483 Dial Gauge MEL 1484 Metric Bolts (3) -Gear Locator MEL 1493 Shims, Joint Installer MEL 1485 Injector Socket MEL 1486 Timing Fixture Lucas Injector MEL 1487 TDC Setting Tool MEL 1488 Injection Pump Removal Tool MEL 1489 Compression Test Adapter (Glow Plug) This Service Letter is provided as technical information Refer to the tool bulletin sent in a previous mailing for applications and pricing The tools are available from: Service Tools 655 Eisenhower Drive Owatonna, MN 55060 ,r--, 1-800-533-0492 7SITOOLDOC Printed in USA DIRECT TO: MELROE / / 	bobcat / DATE: 5 March 1996 MODEL: 873 SUBJECT: RECOMMENDED ENGINE SERVICE TOOLS The following tools are recommended to have available in the shop for service of the Deutz 1011 engine used in the model 873 loader MEL1470 Deutz Engine Tool Kit (all listed below) MEL 1433 Compression Test Adapter MEL 1453 Socket 60 JM P MEL1454 Depth Gauge w/Spacers ,--, 	MEL 1455 Spanner MEL 1456 Valve Spring Assembly Lever MEL 1457 Tone Tool Kit MEL 1458 Adjusting Pin for Crankshaft and Camshaft MEL 1459 Adjusting Pin for Injection Pump Control MEL 1460 Belt Tension Tool for Toothed Belt MEL1461 Crankshaft Seal Tool (front) MEL 1462 Crankshaft Seal Tool (rear) MEL 1463 Camshaft Seal Tool MEL 1464 Valve Stem Seal Tool MEL1465 Crankshaft Gasket Removing Tool MEL 1466 Dolly for Camshaft Gear MEL 1467 Centering Pin, Injection Pump Control Lever This Service Letter is provided as technical information Refer to the tool bulletin sent in a previous mailing for applications and pricing The tools are available from: Service Tools 655 Eisenhower Drive Owatonna, MN 55060 1-800-533-0492 873TOOLDOC Printed in USA DIRECT TO: MELROE 	 ,,,,  	bobcat DATE: 	13 February 1996 MODEL: 	331 EXCAVATOR SIN'S 511920001 & ABOVE 331 EXCAVATOR SIN'S 512911001 -12999 231 EXCAVATOR SIN'S 12000 & ABOVE SUBJECT: PORT RELIEF KIT (PIN 6628092) FOR USE WITH AUGER AND HYDRAULIC BREAKER APPLICATIONS A port relief kit is has been developed for installation in model 331 and 231 excavators listed above We recommend installing this kit in auger and hydraulic breaker attachment applications ,,-, 	The port relief installs in the six spool Gresen hydraulic control valve at the bucket cylinder base end port This port relief limits the pressure in the base end of the bucket cylinder when the bucket spool is in the neutral position This will allow the cylinder to retract if excessive loading occurs, thereby protecting the auger mounting bracket and breaker attachment and pivot pins The relief is set at 3400 PSI Kit (PIN 6628092) is available from Melroe Parts Sales It includes port relief (P/N 6660746) and installation instructions (P/N 6724791 ) Installation time is approximately one and one half hours  r-- 	 Normal warranty policy applies JJIPORTIDOC Printed in USA DIRECT TO: BOBCAT® 	/ / /  D D D D DATE: 20 January 1995 MODEL: ALL LOADERS SUBJECT: NEW IGNITION SWITCH A new ignition switch is now being installed in all current production loaders The new switch is a sealed unit which provides improved protection from moisture and dirt This switch uses a new style key The new key does not work in earlier switches and the earlier keys do not work in the new switch Replacement switches and keys are available from Melroe Parts Sales The new switch is the service replacement for the previous switch (P/N 6519592) The switch panel requires slight modification when installing the new switch in place of the old switch If replacing an old switch order kit (P/N 6724282) This kit contains the following parts: Part No Description Qty 6665606 Switch (w/key) 1 6666202 Key 2 6708693 Ignition plate 1 6708701 Ignition plate 1 6709172 Ignition plate 1 BTI #289 1 (Installation information) When installing the new switch , ensure the ignition plate is in the correct alignment as you  tighten the switch mounting nut When the switch is correctly installed, the ignition plate must match the various key positions The electrical connections to the new switch are the same as the previous switch DIRECT TO: BOBCAT® 	/ / /  D D D D DATE: 23 January 1995 MODEL: 325 and 331 EXCAVATORS SUBJECT: TRACK INTERCHANGEABILITY Model 325 and 331 excavators are available with rubber or steel tracks These tracks are no longer directly interchangeable To change between rubber and steel tracks the rollers, idler wheels, spring spacers and guides must be changed The part numbers for these components are in the parts microfiche Different types of rubber tracks and replacement components have been used Some of these are interchangeable between rubber and steel tracks During service, components may have been replaced with updated components or track upgrade kits may have been installed Because components may have been field installed, it is important to identify the components installed on the excavator before ordering and installing new tracks, track components or track conversion kits BTI E-030 provides component identification for the model 225 excavator BTI E-035 provides component identification for the model 325 excavator BTI E-036 provides component identification for the model 331 and 231 excavators Refer to these BTl's to determine correct part numbers for replacement The following track conversion kits are available (except for excavators sold in Europe) These kits provide the required parts and instructions to convert from rubber to steel or from steel to rubber tracks Kit no Descrition 	Model Instruction no 6589827 Converts from steel to rubber 325 6722984 6589828 Converts from steel to rubber 331 6722985 6589829 Converts from rubber to steel 325 6722986 6589830 Converts from rubber to steel 331 6722987 Printed in USA DIRECT TO: BOBCAT® 	v" v" v" D D D D DATE: 23 January 1995 MODEL: 325 and 331 EXCAVATORS SUBJECT: TRACK INTERCHANGEABILITY Model 325 and 331 excavators are available with rubber or steel tracks These tracks are no longer directly interchangeable To change between rubber and steel tracks the rollers, idler wheels, spring spacers and guides must be changed The part numbers for these components are in the parts microfiche Different types of rubber tracks and replacement components have been used Some of these are interchangeable between rubber and steel tracks During service, components may have been replaced with updated components or track upgrade kits may have been installed Because components may have been field installed, it is important to identify the components installed on the excavator before ordering and installing new tracks, track components or track conversion kits BTI E-030 provides component identification for the model 225 excavator BTI E-035 provides component identification for the model 325 excavator BTI E-036 provides component identification for the model 331 and 231 excavators Refer to these BTl's to determine correct part numbers for replacement The following track conversion kits are available (except for excavators sold in Europe) These kits provide the required parts and instructions to convert from rubber to steel or from steel to rubber tracks Kit no Description Model Instruction no 6589827 Converts from steel to rubber 325 6722984 6589828 Converts from steel to rubber 331 6722985 6589829 Converts from rubber to steel 325 6722986 6589830 Converts from rubber to steel 331 6722987 Printed in USA DIRECT TO: V BOBCAT® V V DATE: 	8 February 1995 MODEL: 	853 (5/N 508411001-508415003) 853 H (S/N 509711001-509715005) 853Plus (S/N 510250001-510250004) 853 Plus H (S/N 510375001-510375004) SUBJECT: 	FUEL TANK CONTACT WITH ENGINE OIL PAN For some time a low profile fuel tank has been installed in production model 853 loaders This provides additional clearance with the engine oil pan If you are servicing a model 853 loader for damage due to contact between the engine oil pan and the fuel tank, we recommend the following: Check the machine serial number against those listed above These loaders have fuel tanks with less clearance with the engine oil pan If this original fuel tank is still in the loader, fuel tank replacement is recommended Order and install fuel tank (P/N 6708527) NOTE: Engine mounts generally require replacement if damage has resulted due to contact of the engine oil pan and fuel tank Refer to BTI 273 for correct engine mount replacement if required  Normal warranty policy applies The original fuel tank can easily be identified It does not have a formed hole through the middle of the tank (see photo) Remove the fuel tank and clean debris from · the underside Through Hole t Identifies Latest Tank Printed in USA DIRECT TO: BOBCAT® ur" ur" ur" D D FIELD MODIFICATION D D DATE: 15 February 1995 MODEL: 325 EXCAVATOR (S/N 511820520 -511820953) SUBJECT: NOISE IN SWING MOTOR CIRCUIT We have received reports of noise coming from the swing circuit when the house is swung left or right and is stopped quickly This noise may come from the counterbalance relief valves which are located at the swing motor This affects only model 325 excavators that are equipped with a counterbalance valve (see serial numbers listed above) A new relief valve has been developed which eliminates this noise This valve is now installed in current production machines serial number 511820954 and above The new relief valve is (P/N 6666876) and is identified by CBCG LDV stamped on the side It replaces the old relief valve (P/N 6665712) which is identified by CBCG LK5 stamped on the side If you are servicing an affected machine for noisy counterbalance relief valves as described above, new relief valves (P/N 6666876) should be installed New relief valves are available from Melroe Parts Sales Melroe Company will give compensation for the cost of new relief valves (P/N 6666876) and one (1) hour labor to install them in an affected machine One (1) additional hour is allowed for travel time for retailed machines This offer expires on 15 February 1997 Printed in USA DIRECT TO: BOBCAT® 	/ / / D D D D DATE: 	17 February 1995 MODEL: 	320, 325 AND 331 EXCAVATORS All 12000 SERIES 220, 225 AND 231 EXCAVATORS SUBJECT: NEW DRIVE MOTOR, OIL CHANGE INTERVAL A new oil change interval is now recommended for the track drive motors in the model excavators listed above These are machines equipped with Kayaba drive motors We now recommend changing the fluid after the first 100 hours of operation and every 1,000 hours there after Two previous recommendations were to change the fluid every 1,000 hours One also required changing after the first 250 hours The other did not This new recommendation replaces both old recommendations The procedures for changing drive motor fluid follows The procedures have not changed MODEL 320 AND 220 (12000) With the machine on a level flat surface, position the motor so the plugs are in the position shown Remove the bottom and top plugs to drain the fluid After all the fluid is removed, install and tighten the bottom plug Add 3 quarts (3 Liter) of SAE 90W gear lube through the top plug hole and install the plug This is an initial fill only Continued on the reverse side Printed in USA Move the excavator until the plugs are positioned parallel to the ground Remove one of the outer plugs Add SAE 90W gear lube through the hole until it is level with the hole Install and tighten the plug Repeat for the other motor CD-7405 MODEL 325, 331, 225 (12000) AND 231 (12000) With the machine on a level flat surface, position the motor so the plugs are in the position shown Remove the bottom and top plugs to drain the fluid After all the fluid is removed, install and tighten the bottom plug Add SAE 90W gear lube through the top plug hole until the fluid is level with the bottom edge of the plug hole This will be approximately 55 quarts (5 Liter) Install and tighten the plug The Operation & Maintenance and Service Manuals are in the process of being updated DIRECT TO: BOBCAT® cY°  cY° cY° 0 0 FIELD MODIFICATION 0 0 DATE: 18 February 1995 MODEL: 231 EXCAVATOR (S/N 12001-12620) SUBJECT: WORK GROUP HOSE REPLACEMENT A new work group hose replacement kit has been developed for 12000 series model 231 excavators This kit provides a new design for the work group hose installation Newly designed hoses, special parts and instructions for machine modifications are included If you are servicing an affected machine with Kit 6595807 repeat work group hose failures (wear through, kinks or breakage) we recommend installing this new kit (P/N 6595807) This kit will reduce the possibility of hose damage in the boom swing frame area and at the frame opening Order the kit from Melroe Parts Sales Melroe Company will give compensati n for the cost of kit (P/N 6595807) and sixteen (16) hours labor to install the kit One (1) dditional hour is allowed for travel time for retailed machines This offer expires on 18 Feb uary 1996 Printed in USA DIRECT TO:  v' / BOBCAT® / D D D D DATE: 20 February 1995 SUBJECT: REPLACEMENT SPOOLS FOR MELROE CONTROL VALVES Replacement spools are now available for Melroe manufactured hydraulic control valves Replacement spools may be installed in place of damaged spools provided the valve body · and spool bore are in serviceable condition For example a spool with wear or pitting in the seal area NOTE: Melroe warranty policy remains the same If the hydraulic control valve is still under warranty and a spool requires replacement, do not replace the individual spool, replace the entire hydraulic control valve When Melroe hydraulic valves are Paint manufactured, spools are selected for proper or fit Currently, three sizes are used The size Number difference between spools is approximately twenty five millionths (000025") Spools are currently identified by a small paint spot on the end of the spool (linkage end) This current paint identification system has been in use since November 1992 MC-1606 Continued on the reverse side Printed in USA · For these valves the color coding provided below can be used for replacement spool selection These are valves with an identification number 22,000 and above For spool replacement in valves with an identification number 19,999 and below, the color code on the end of the spool should not be relied upon for spool replacement For these, follow the procedure for spool selection which follows If the color can not be identified, use the spool selection procedure We recommend dealers stock all three sizes to allow for selection during the spool selection procedure In the near future, production spools will be stamped with a number on the end of the spool This number will indicate the correct replacement spool Spool Part Numbers by Model Machine models: 753, 753H, 753L, 763, 773, 7753, 853, 853H, 2410 articulated, 220 excavator P/N Section Color No Size Note: Color and size 6666576 Lift Red 1 Large identification is for current 6666577 6666578 6666579 Lift Lift Tilt Green Black Red 2 3 1 Med Small Large production only Valve identification number 22,000 and above 6666580 Tilt Green 2 Med 6666581 Tilt Black 3 Small Machine models: 440, 443, 540 series, 640 series, 740 series, 843, (1600, 2000, 2400 articulated) P/N Section Color No Size 6666582 Lift Red 1 Large 6666583 Lift Green 2 Med 6666584 Lift Black 3 Small 6666585 Tilt Red 1 Large 6666586 Tilt Green 2 Med 6666587 Tilt Black 3 Small Note: Color and size identification is for current production only Valve identification number 22,000 and above Continued · r\ Machine models: 450, 553 series   , P/N Section Color No Size Note: Color and size 6666588 Lift Red 1 Large identification is for current 6666589 Lift Green 2 Med production only Valve 6666590 Lift Black 3 Small identification number 22,000 and 6666591 Tilt Red 1 Large above 6666592 Tilt Green 2 Med 6666593 Tilt Black 3 Small Spool Selection Procedure The cause for spool damage must be determined and corrected Any contamination must be completely removed from the system Use a small light and carefully inspect the bore for scratches, scores, or cracks Clean the replacement spool and inspect the spool for any damage from improper handling or manufacture Check for nicks or burrs Inspect the sealing area for scratches which would cause leaks With no spool seals in place, lubricate the spool and bore Carefully install the spool in its bore Place the spool in the neutral position Rotate the spool one turn and check for freedom of movement Move the spool 1 /2" either side of neutral and check for smooth movement The spool may fit snug but must not require excessive force to move A good test to determine if the spool is too tight is to hold the valve side ways over a protective pad Raise the spool almost out of its bore and release The weight of the spool atone must allow the spool to drop to the pad If the spool will not drop through, it must not be used It is either too tight, has damage, or the valve bore has damage If the spool is too tight try the next smallest spool The above part numbers are being added to parts microfiche and manuals as they are updated BOBCAT@ DIRECT TO: v" v" v" D D D D DATE: 21 March 1995 MODEL: 753, 763, 773 AND 853 SUBJECT: GOODYEAR RUBBER TRACKS Goodyear rubber tracks are now approved for model 753, 763, 773, and 853 loaders provided both fron drive chains are removed Removing the front drive chains reduces chain stress and provides longer service life for the remaining rear drive chains This eliminates the effect of front and rear chains working against each other in a rubber track application All new Goodyear rubber track installations must have the front chains removed for warranty coverage We recommend the front drive chains be removed in existing rubber track applications as well Chain removal costs are the dealer's responsibility When installing Goodyear rubber tracks it is important to ensure the track is installed within the recommended crunch level specification The crunch level specification in all current applications is 2"-35" crunch The crunch is the difference between the wrap around length (see diagram) and the track inside length The Goodyear installation manual provides minimum and maximum average tire circumference limits for each track used with a given wheel base It is important to be within these limits The following is an example for 753 track installation Track (P/N 16575150XAXAX23035) The 753 wheel base is 355" The installation manual shows the average tire circumference must be between 953" and 968" to provide the proper crunch If the average circumference is not within specified limits, one or more tires must be replaced cu11wv,,r- DIRECT TO: BOBCAT® 	cY cY cY D D  D V) v-tl-FIELD MODIFICATION D '}--CJerf vPrIfci "" f DATE: 27 March 1995 fd tr1 s(uf MODEL: 331 EXCAVATOR (S/N 511920001 -511920461) 1 ",, ,/ 231 EXCAVATORS (508912469 -508912620) llLj'( , ·t-e  0 r I'/ I> ''"'' 	( 't t-"t' r 4'3"-( -f>o,'ftLJssuBJECT: NEW HYDRAULIC PUMP Melroe Company has determined that Barnes hydraulic pumps installed in model 231 and 331 excavators listed above, do not meet our specifications A new hydraulic pump is now available This hydraulic pump has internal improvements that provide longer service life New hydraulic pumps (P/N 6666930) are being sent to affected dealers Dealers are asked to immediately install the new pumps into machines that have serial numbers listed above Follow the pump replacement procedure provided in the 331 excavator service manual (P/N 6724222) page 2-10 Also follow this procedure for model 231 excavators Melroe Company will give compensation for two (2) hours labor to install the new hydraulic pump One (1) additional hour is allowed for travel time for retailed machines Printed in USA DIRECT TO: BOBCAT@ / / / D D D D DATE: 13 April 1995 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICS™) SUBJECT: NEW SEAT SENSOR MAGNET COLLAR (P/N 6666608) A new seat sensor magnet collar is now installed in current production BIGS equipped loaders The new magnet collar is tapered and provides additional clearance to reduce wear between the magnet collar and sensor body The new magnet collar is easily identified by its light gray color If the seat magnet collar requires replacement, only use new magnet collar (P/N 6666608) The previous magnet collar (P/N 6665521) can still be used as a service replacement in the seat bar sensor The new magnet collar (P/N 6666608) can not be installed in the seat bar sensor ,, ,,, ,, ' /' I , ( : ,  , T J+ afD )? i /'' : : I , :: ! ' : : ,P I Replacement magnet collars are available /: ; : : 7/! I f !: I I from Melroe Parts Sales :: t :: : /7 I o ---i""· I L----- --J The above is provided as technical ' ---, er o : : information Magnet Collar-+ 00 ' I +  I ( ,--,  Printed in USA BOBCAT® DIRECT TO: cY cY cY D D D FIELD MODIFICATION D DATE: 18 April 1995 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICSTM) SUBJECT: NEW SIDE-PIVOT SEAT KIT (P/N 6708913) A new side-pivot seat kit has been developed for BICS equipped loaders With this kit the seat pivots sideways when an operator sits in the seat The side-pivot seat kit replaces the original seat mount in BICS equipped loaders which pivot from front to rear This includes the standard, optional Milsco and Grammer suspension seats The Side Pivot Seat Kit (P/N 6708913) can be installed if the operator is inconvenienced by experiencing temporary interruption of the loader's hydraulic lift and tilt functions If you have received this complaint, order kit (P/N 6708913) from Melroe Parts Sales Follow installation instructions (P/N 6724258) included with the kit Melroe company will give compensation for the cost of the kit and one (1) hour labor for installation One (1) additional hour is allowed for travel for retailed machines This offer expires April 18, 1996 ' '  H: '  ·ff "19 : : -:-:  : u : :/ :: ----: :, : 1 : : -1---· : I : :  e , fl C> C> : :/:-­ I : e I I :/ 1 e :-:-: O I · ---· : : -' : I : I I I ' : ' e e & I ft <ii> e ' ! Installation for Standard Seat Shown Printed in USA DIRECT TO: BOBCAT® 	/ / /  0 0 0 0 DATE: 	9 May 1995 MODELS: 	MODELS 540, 640, 740, 850 SERIES 753 and 553 (W/OPTIONAL CAB ENCLOSURE) SUBJECT: FRONT DOOR WINDOW RETAINER KIT (P/N 6708990) NOTE: This Service Letter replaces Service Letter dated 10 April 1994 Part numbers are revised Retainers have been added to the front window in loaders equipped with the right hinge optional cab enclosure Four retainers are bolted to the front door frame The retainers provide additional support for the front window This will reduce the possibility of the front window separating from the adhesive This change is also made to the front door in field installed kits With the addition of retainers, the window is now replaceable on right hinge doors Previously windows were not replaceable, the entire door frame required replacement The 1/4" thick replacement standard window for models 540, 640, 740, 850 series 753 and 553 is (P/N 6568705) The 1/4" thick replacement standard window for long wheel base models 753L, 763, 773 and 7753 is (P/N 6703755) A kit (P/N 6708990) has been developed for replacing a window The kit is available from Melroe Parts Sales and includes the following parts:  Normal warranty policy applies Printed in USA BOBCAT@ DIRECT TO: / / / D D D D DATE: 12May1995 SUBJECT: PROPYLENE GLYCOL COOLANT NOTE: This Service Letter replaces Service Letter dated 11 April 1994 Typographic correction Propylene glycol (PG) is now available in a full strength concentrated formula Previously it was only available premixed The concentrated formula allows increasing the PG to water ratio in the system if the solution is tested and found to be less than the recommended mixture Concentrated PG is available in one gallon containers (P/N 6724354) Premixed PG is available in one gallon containers (P/N 6724094) Both are available from Melroe Parts Sales The recommended antifreeze to water ratios are: PG and water 53% PG-47% Water Protection to -34° F (-366 C0) Ethylene glycol and water 50% EG-50% Water Protection to -34° F (-366 C0) NOTE: One gallon and one pint of PG (concentrated) mixed with one gallon of water provides the recommended 53%/47% ratio Maximum antifreeze to water ratios are: PG and water 58% PG-42% Water Protection to -50° F (-455 C0) Ethylene glycol and water 60% EG-40% Water Protection to -65° F (-539 C0) DO NOT EXCEED THE MAXIMUM ANTIFREEZE TO WATER RATIOS! The proper ratio of antifreeze and water must be strictly adhered to Too much antifreeze reduces cooling system efficiency and may cause serious premature engine damage Too little antifreeze reduces the additives which protect the internal engine components and reduce the boiling point and freeze protection of the system This may also cause serious premature engine damage Continued on the reverse side Printed in USA When checking the freeze protection level of a cooling system, the following factors must be considered: Adding antifreeze to the system: Premix the solution to the proper ratio before adding to the system Do not add full·-· strength concentrated antifreeze to the cooling system Full strength concentrate may cause engine damage before it gets adequately mixed in the cooling system Premixed propylene glycol can be added to systems which currently use Ethylene glycol Proper testing tool for type of coolant in the system: The type of antifreeze determines the tool required for testing the freeze level Ensure you are using a tool that is specifically designed for the type of antifreeze in the system Consult the tool instructions The refractometer OEM 1044 available from OTC can be used with either type This refractometer has two scales, one for PG and one for EG Make sure you are using the proper scale for the type of antifreeze in the system If the system has a mixture of PG and EG split the difference or use the PG scale Tool calibration, temperature compensation and proper use: For accurate measurements it is imperative that the tool is calibrated and the instructions are followed Some refractometers are not temperature compensated This means you must have the antifreeze and the tool at the same constant temperature Usually at some specific temperature, for example 70° F, or within a specific temperature range If you test out of this range the results can be very inaccurate, depending on the tool Temperature compensated refractometers also have a limited temperature range Hot coolant from the engine on a much cooler refractometer will give inaccurate readings Likewise, cold coolant being tested with a warm (room temperature) refractometer will give inaccurate readings We have experimented with some different tools designed for use with PG antifreeze and have found some to be very inaccurate Use a good quality tool As engines become more efficient and the demands placed on them increase, the cooling system demands also increase Following the recommended interval for antifreeze replacement ensures proper antifreeze additive strength for protecting the cooling system BOBCAT@ DIRECT TO: / / / D D D D DATE: 	17May1995 MODEL: 	225 EXCAVATOR (S/N 12001 & Above) 231 EXCAVATOR (S/N 12001 through S/N 12597) SUBJECT: SWING GEARBOX SEAL LEAKAGE We are aware of a condition which exists in some model 225 and 231 excavators This affects serial number 12,000 series machines only The swing gearbox drain oil flow is currently routed through a drain block, hydraulic control valve, oil cooler, filter then to the reservoir This results in significant drain line back pressure In some cases this results in swing gearbox seal leakage Back pressure of 100-150 psi has been noted If you are servicing a swing gearbox for seal leakage, we recommend changing the drain line routing as described below This will reduce the back pressure to the gearbox seal and help prevent further seal leakage Changing the drain line routing will lower the back pressure to 10 psi or less To change the drain routing you will need to order one each of the following parts This procedure will take approximately one and one half hours to complete P/N Description 6534012 hose 43K-5 4-way cross fitting *36K-5 Cap *36K-6 Cap * Only one cap is required Size determined by machine inspection Continued on the reverse side Printed in USA Remove the seat and seat mount, swing motor cover, front floor panel and the floor panel under the seat The swing gearbox case drain connects to the drain block as shown in the diagram Do not change the gearbox drain hose connections DrainBlock Remove and discard the hose (A) which connects between the drain block and the three spool hydraulic control valve Install the cap fitting (B), (P/N 36K-5) or (P/N 36K-6) onto the open port of the hydraulic control valve NOTE: You may find this hose connected to the drain block at location 0 or @ 0 Remove the three hoses from the tee fitting that is located behind and to the right of the swing motor The three hoses connect to the right hand joy stick drain, the left hand joy stick drain and the reservoir Install the same three hoses onto the new 4-way cross fitting Install one end of the new hose (P/N 6534012) onto the 4-way fitting Connect the other end to the drain r'\ 	block where hose A was removed (location O or@) Ensure the hoses are routed correctly and do not rub on other components Check the connections for leaks Tee Fitting / To Left Joystick Hydraulic Reservoir  Normal warranty policy applies DIRECT TO: BOBCAT@ 	 0 0 0 0 DATE: 	17 July 1995 MODEL: 	853 (S/N 512818874 -512818900) (NON HIGH FLOW ONLY) European 853 (S/N 508418086 -508418095) SUBJECT: REAR AUXILIARY HYDRAULIC KIT (P/N 6706163) INSTALLATION We are aware of a condition which affects the model 853 loaders listed above This condition only affects those machines if you are installing rear auxiliary hydraulic kit (P/N 6706163) This condition DOES NOT affect those machines with optional high flow hydraulics The green/red stripe wire in the left instrument panel must be connected to ground when installing the rear auxiliary hydraulic kit If this wire is not connected to ground, the rear auxiliary hydraulics will not function properly This change is installed in current production machines Remove the left instrument panel Find the green/red stripe wire (57F) and the black pair of wires Both of these have a black 90° connector on the end Attach the two connectors together with jumper lug (P/N 6667530) This jumper lug is available from Melroe Parts Sales Lug 6667530 P-5888 Printed in USA DIRECT TO: BOBCAT@ 	/ / / D D D D DATE: 3August1995 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICS™) SUBJECT: NEW BICS HARNESS CONNECTOR AND REMOTE START SWITCH ADAPTER A new electrical connector is now installed in current production loaders equipped with BICS Because the new connector and old connector are not compatible, an adapter has been designed for use with remote start switch MEL 1429 The adapter is MEL 1429-1 When installing the remote start switch in machines with the new BICS connector, use the adapter See photo of old and new connectors below Old 	New P-5887 This new adapter is being sent to all dealers free of charge who have purchased remote start switch MEL 1429 The adapter will be included with the remote start switch on future orders Printed in USA DIRECT TO: BOBCAT@ 	/ / / D D D D DATE: 16 August 1995 MODEL: ANGLE BROOM ATTACHMENT SUBJECT: ATTACHMENT HARNESS KIT (P/N 6709152) A new harness changes the electrical circuit to prevent fuses from blowing from an overload condition This could most likely occur when additional electric accessories like lights are also used The new harness is now available and provides a dedicated fused  electric power source for the angle broom attachment Order harness kit (P/N 6709152) from Fuse Melroe Parts Sales The kit provides Installation Instructions (P/N 6722954) ToGrd T and harness (P/N 6707346) CP-----{JU!Jl 'iOnnnntJtlllOOtltl!lU'JD!Joounn!l!l!llllltltlOOllllllUOIJllllll!l!l!lllmJOll>-- Disconnect the negative battery cable To +12V 	Fused Power Connect the round lug from the red wire to the "Battery" connector at the starter solenoid Connect the round lug from the black wire to a suitable ground The connector now supplies fused power to supply the angle broom attachment Continued on the reverse side Printed in USA If the loader is equipped with the latest style electric control connectors, disconnect the existing two pin connector with the single red/white wire (located under the cab) Connect the electric control harness connector to the new harness If the loader is equipped with the earlier style electric control connector you will have to improvise a connector for the new harness Remove one or more connectors and use locally supplied mating connectors The power wire for the angle broom electrical connection is a brown or orange wire Both colors have been used in the past Secure the harness to the loader with cable ties  Normal warranty policy applies BOBCAT@ DIRECT TO: / / / D D D D DATE: 18 August 1995 MODEL: TWO-POSITION HYDRAULIC BREAKER FRAME SUBJECT: MODIFICATION FOR USE WITH MODEL 873 LOADER The two position hydraulic breaker frame has been changed for use with the new model 873 loader The two stops on the bottom of the frame are redesigned for use with the model 873 loader These are frames with new part number (6709407) They are easily identified by the new shape of stop (see drawing below) When installing an existing two position frame with old style stops onto a model 873 loader, the old style stops will interfere with the lift arm ends The old style stops must be removed and the new style stops installed Order two new stops (P/N 6709404) from Melroe Parts Sales c- Old New6709404 MC 2178 Continued on the reverse side Printed in USA 1 Measure and record the location of the existing stops from the outside edge of the frame in two locations Measure and record the depth of the stop from the edge of the frame Remove the old stops using a torch and grinder Using a welder, install the new stops in place of the original stops using the measurements you recorded earlier Use a 5/16" fillet weld  No warranty is implied 2 DIRECT TO: BOBCAT® cY' c:Y' c:Y'  D D D FIELD MODIFICATION o DATE: 19August1995 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICS™) (SEE MODEL AND SERIAL NUMBER LIST ON LAST PAGE) SUBJECT: Q) BICS CONTROLLER SOFTWARE CHANGE BICS SAT SENSOR RE-POSITIONING KIT (P/N 6710544) Q) BICS CONTROLLER SOFTWARE CHANGE A software change to the BICS system controller that affects how the seat sensor functions was implemented on loaders manufactured during the week of June 12, 1995 The software change addresses operator inconvenience caused by momentary interruption of the loader's lift and tilt hydraulic  	functions This could occur with short or lightweight operators or in some applications when the loader is used on a slope Under these conditions the operator could raise up off the seat and cause momentary interruption Of the loader's lift and tilt hydraulic fUl"JCtions The software change eliminates the possibility of momentary interruption of the lift and tilt hydraulic functions under the conditions described above Previous loaders had a one second delay in the BICS seat sensor system The new software extends the delay until the operator raises the seat bar The new BICS controller (P/N 6667 468) can be installed· on earlier machines if the operator is inconvenienced by experiencing momentary interruption of the loader's hydraulic lift and tilt functions If you have received this complaint and the machine has the old controller (see machine serial numbers on the reverse side), order and install this new BICS controller (P/N 6667468) from Melroe Parts Sales Follow the removal and installation procedure in the 753, 763, 773 service manual (P/N 672401 )or the 853 service manual (P/N 6724012) for all models After installation, perform the BICS inspection procedure found in the same service manuals Continued on the reverse side Printed in USA 1  BICS SEAT SENSOR RE-POSITIONING KIT (P/N 6710544) The SICS seat sensor has been re-positioned on current production loaders The new sensor position provides added clearance between the magnet collar and the sensor This improvement will help reduce excessive wear or possible breakage of the seat sensor caused by dirt or debris in certain applications If you have this complaint, order seat sensor re-positioning kit (P/N 6710544) from Mel roe Parts Sales This kit provides the parts required to re-position the seat sensor and includes the latest tapered magnet collar (light gray in color) It can be installed on machines with serial numbers listed on the last page of this service letter The kit (P/N 6710544) contains one each of the following parts: P/N DESCRIPTION REF 6724460 Instructions 500-12 Hex lock nut A 25E-10 Washer B 6710539 Screw c 6666608 Magnet collar D 6665000 Connector holder E 6664221 Snap-in Retainer F Install the kit following the installation instructions provided Mel roe Company will give compensation for the cost of the controller and/or the seat sensor re-positioning kit The following warranty compensation for labor will be given: ·one half (1/2) hour labor for installation of the SICS controller One half (1/2) hour labor for installation of the seat sensor re-positioning kit One (1) additional hour is allowed for travel time for retailed machines to install both the new controller and the seat sensor re­positioning kit This offer expires 19 August , 1996 When filing warranty claims electronically use service code 01 R60 Continued on the reverse side - - CD Serial numbers with old BICS controller: DOMESTIC MACHINES: 450 S/N 561711273 & BELOW (EXCEPT 11266) 453 S/N 561811163 & BELOW 553 S/N 513011577 & BELOW 753 S/N 512716001 -512721880 763 S/N 512212001 -512214946 (EXCEPT 14898, 14919 & 14943) 773 S/N 509635001 -509637 443 853 S/N 512816001 -512819409 (EXCEPT 19404) 873 S/N 514111001 -514111108 (EXCEPT 11104 & 11107) 953 S/N 513111001 -513111216 EUROPEAN MACHINES: 450 S/N 562011048 & BELOW 453 S/N 561911337 & BELOW 553 S/N 513030001 -513031666 753 S/N 508693001 -508693865 753 S/N 508630001 -508630600 753H S/N 511476001 -511476342 763 S/N 512440001 -512440327 773 S/N 509616001 -509616263 853D S/N 508418001 -508418108 853DH S/N 509718001 -509718136 873 S/N 514211001 -514211015 953 S/N 513115001 -513115040 Cf) Serial numbers with seat sensor that is not re-positioned (serial numbers are approximate) All machines above these serial numbers have the seat sensor re-positioned DOMESTIC MACHINES: 553 S/N 513011705 & BELOW 751 S/N 514711001 -514711076 753 S/N 512716001 -512723203 763 S/N 512212001 -512215742 773 S/N 509635001 -509637862 853 S/N 512816001 -512820175 873 S/N 514111001 -514111230 953 S/N 513111001 -513111275 EUROPEAN MACHINES: 553 S/N 513030001 -513031802 753 S/N 508693001 -508693940 753 S/N 508630001 -508630826 753H S/N 511476001 -511476379 763 S/N 512440001 -512440331 773 S/N 509616001 -509616295 853D S/N 508418001 -508418137 853DH S/N 509718001 -509718180 873 S/N 514211001 -514211034 953 S/N 513115001 -513115045 NOTE: Model 450 and 453 loaders do not have the seat sensor re-positioned at this time The seat sensor will be repositioned in the near future · 3 DIRECT TO: BOBCAT@ 	/ / /  D D D D DATE: 21August1995 MODEL: 753, 753H, 753L, 763, 773, 7753 and ALL 850 SERIES SUBJECT: NEW BOSS OPERATING UNITS Two new BOSS operating units are now available BOSS unit (P/N 6666916) is now installed in current production loaders listed above Back-up BOSS unit (P/N 6666918) is available for temporary field installation The new units have internal design changes that allow them to be used for each of the models listed above The changes also incorporate improvements that allow the units to be field initialized using the initialization cartridge in the BOSS diagnostic tool They can be initialized for each model listed above The changes do not affect the operation of the machine The new units are available from Melroe Parts Sales Both units are supplied un­initialized (P/N 6666916) must be field initialized for your particular machine model, serial number and hours Replacement BOSS unit (P/N 6666916) can also be ordered initialized at your request Continued on the reverse side Printed in USA 1 The existing diagnostic tool can not accept models 763,773, 753H & 753L, therefore, current operation is as follows: When using the BOSS tool for diagnostics with a model 763, 773, 753H & 753L you must enter model 7753 as follows: Display will show invalid model number: Invalid Model#: Model# XXX The next display will ask you to enter model number You Enter model # MUST enter 7753 DO NOT enter the machine model number Model# 7753 Enter yes After entering 7753 the display will show: Correct? (yes or no) The display will then show: Model# 7753 Update computer? YOU MUST ENTER NO The tool will then provide the (yes or no) correct levels for monitoring system operating parameters DO NOT ENTER YES TO "Update computer?" IMPORTANT: If you enter yes to "update computer?" the BOSS unit will be updated with incorrect operating parameters The BOSS unit will continually provide erroneous warning and shut down information making the machine inoperable NOTE: Normally when asked "Update computer?" yes/no", yes should be entered only when initializing an un-initialized back-up BOSS unit (P/N 6666918) or the old back-up BOSS unit (P/N 6661110) Model 753, 7753 and all 850 series operation is unchanged I 2 DIRECT TO: BOBCAT@ 	/ / / D D D DATE: 21 September 1995 MODEL: 763 S/N 512215736 & ABOVE (ALSO SIN'S 15690, 15702, 15703, 15707, 15716, 15719 & 15735 773 S/N 509638119 & ABOVE EUROPEAN MACHINES 763 S/N 512440332 &ABOVE 763 HIGH FLOW S/N 512612002 &ABOVE 773 S/N 509616302 & ABOVE SUBJECT: NEW SPRING LOADED DRIVE BELT IDLER ASSEMBLY A new spring loaded drive belt idler is now installed on model 763 and 773 loaders (see serial numbers above) The new idler assembly is spring loaded to maintain proper drive belt tension The idler has a visual gauge to indicate proper belt tension With this new design, a spring scale is no longer required for adjusting belt tension A new decal is located inside the tailgate and provides the adjustment procedure This procedure will be added to the service manual Continued on the reverse side Printed in USA 1 SPRING LOADED IDLER ADJUSTING PROCEDURE IMPORTANT I The belt tension Is maintained by a spring The working range Is Indicated by a pointer (Item 1 ) DO NOT use the specifications or the tool PIN MEL 1405 which was used for the previous fixed Idler pulley The tool PIN MEL 1405 can be used a prybar to reset the Idler tension spring 1 The pointer will be at the 1 o'clock position when the idler is not under spring tension Push the idler assembly against the belt (use a prybar) 2 The pointer wlU be at the 3 o'clock position when the idler stop is bottomed out From the 3 o'clock position, raise the idler slighty so that the idler is operating on the spring tension Tighten the mounting bolt (Item 2) to 25-28 ftlbs (34-38 Nm) torque IMPORTANT I DO NOT load the idler against its travel stop in the 3 o'clock position 3 Run the engine for a few minutes Stop the engine and recheck the pointer position Readjust if necessary 4 After the idler has been in service, readjust when the pointer reaches the 1 o'clock position 5 See Service Manual for more detailed information SW 95 6709030 IMPORT ANT: The decal contains an important note to NOT load the idler against its travel stop in the 3 o'clock position This would prevent the spring from performing its intended function and will reduce the service life or cause a failure of the idler assembly and drive belt The new idler assembly (P/N 6705738) is available from Melroe Parts Sales The idler will be serviced as an assembly only Because of the limited supply of idler assemblies, the machine serial number and hours will be required to place an order At this time spring loaded idlers will not be available for other models All replaced idler assemblies must be returned to the Melroe Company Warranty Department Idler assemblies will only be supplied for those models and serial number machines that were originally equipped with the new spring loaded idler assembly 2 DIRECT TO: cY BOBCAT® cY cY  D D SAFETY NOTICE D D DATE: 3 October 1995 MODEL: LOADERS WITH BOBCAT INTERLOCK CONTROL SYSTEM (BICSTM) (SEE MODEL AND SERIAL NUMBER LIST ON LAST PAGE) SUBJECT: CHECK VALVE REPLACEMENT FOR BICS LIFT AND TILT LOCK VALVES A Safety Notice dated 3 October 1995 (attached) was mailed to all owners and dealers of affected loaders This Safety Notice requests owners to immediately make arrangements with their Bobcat dealer to have new check valves with correct compression springs installed in the lift and tilt lock valves Two new check valves per loader are being sent to affected dealers for installation into those loaders with serial numbers listed on the last /"'- page of this letter This modification will be provided at no cost to the owner New check valves with correct compression springs can be identified by the number 4400 stamped on the end of the end cap The new check valves may have a short or tall end cap The (P/N 6665610) has not changed New check valves are now installed in all current production BICS equipped loaders Melroe Company now asks its dealers to take the following immediate actions: 1 	 Contact all owners of affected BICS equipped loaders (listed on the last page) and make arrangements to have the new check valves installed 2 	 Install the new check valves in the lift and tilt lock valves US and Canada dealers must return old check valves to the vendor in the enclosed prepaid return envelopes All other dealers must destroy old check valves See reverse side for installation procedures 3 	 Correct all affected loaders in your dealer inventory Printed in USA 1 The check valve replacement procedure for each model is similar The procedure provides instructions when different for each model A WARNING This service procedure can be performed with the lift arms fully down and the attachment flat on the ground If this procedure is performed with the lift arms raised you must:  	 Remove the attachment  	 Retract the Bob-Tach fully  	 Raise the lift arms and install an approved lift arm support device Never work on a machine with the lift arms up unless the lift arms are secured by a lift arm support device Failure to use an approved lift arm support device can allow the lift arms or attachment to fall and cause injury or death W-2059-0991  	Ensure the lift arms are fully lowered against the lift arm support device AwARNING: If this procedure is not followed the lift arms can suddenly drop and the Bob-Tach can suddenly rotate down when the check valves are removed Engage the parking brake and turn the engine off Raise the operator cab LIFT LOCK VALVE -CHECK VALVE REPLACEMENT (ALL MODELS EXCEPT 450 & 453) Remove the two throttle lever mounting bolts CD Remove the top right side steering panel mounting bolt Remove the red lift bypass knob and jam nut@ 853 & 873 ONLY Remove the right side shock absorber mounting bolt and nut to allow the right side of the panel to be raised 2 873 ONLY Pry up on the right side of the steering panel using an appropriate pry bar Place a short wooden block under the panel (see photo) Remove the check valve and install the new check valve Remove the wooden block and lower the right side of the panel ALL Raise the right side of the steering panel only as far as necessary for valve replacement (panel bent upwards for photo) Remove the check valve and install the new check valve Lower the right side of the panel and install the panel mounting screw 853 & 873 ONLY Reinstall the right side shock absorber, mounting bolt and nut ALL Install the throttle lever mounting bolts Make sure the throttle linkage is properly installed in the throttle lever Install the jamb nut and red lift bypass knob Tighten the jamb nut TILT LOCK VALVE -CHECK VALVE REPLACEMENT (ALL MODELS EXCEPT 450 &453) Remove the old check valve and install the new check valve 753, 763 & 773 Tilt lock valve is located on the right side fender beneath the fuel inlet hose (753 shown) ­ 3 751 The tilt lock valve is located under the hydraulic reservoir (see photo) The check valve is located on the rear most side of the tilt lock valve Access the check valve in the engine compartment by opening the tailgate It is located just forward and to the right of the engine A tubeline is directly in front of the check valve To remove the check valve, disconnect the end of the tubeline from the tilt lock valve This will provide clearance for check valve replacement 853 The tilt lock valve is located on the right side fender The check valve is located on the rear most side of the tilt lock valve (see arrow) The check valve can be removed without removing tubelines Hoses are removed for photo clarity 873 The tilt lock valve is located against the right side fender forward of the lift lock valve The check valve is difficult to reach, however, it can be removed without removing the steering panel For photo clarity the steering panel is removed 873 cont Access the check valve from a point near the hydraulic control valve Use a long extension (3/8" drive) on a socket wrench You may temporarily remove the right side plastic access plug to help hold the socket wrench extension 553 Access the tilt lock valve at the engine compartment through the tailgate area The valve is located on the right r-- 	side just above the battery Replace the check valve located on the bottom of the tilt lock valve LIFT AND TILT LOCK VALVE CHECK VALVE REPLACEMENT FOR MODELS 450 & 453 The lift and tilt lock valve is located under the operator seat The two check valves are side by side on the top of the valve Replace both check valves The front panel is removed for photo clarity Remove the tubelines CD Loosen fitting (?) and move hose slightly to replace the check valves @ ALL MODELS After replacing the lift lock and tilt lock check valves, lower the operator cab and install the cab hold down plate and nut (both sides) Remove the lift arm support device Conduct the SICS inspection procedure described on the next page This inspection procedure can also be found in the Operation & Maintenance manual Check the machine for proper operation 5 BOBCAT INTERLOCK CONTROL SYSTEM (BICS™) Inspecting the BICS Controller (Engine STOPPED ­Key ON) 1 	 Sit in the operator's seat Turn key "ON", lower the seat bar and disengage the parking brake All five (5) BICS Controller lights should be "ON" (Items 1, 2, 3, 4 & 5) [A) 2 	 Engage the parking brake, raise the seat bar fully Seat bar light (Item 2) [AJ, valve light (Item 3) [AJ and traction light (Item 4) [AJ should be "OFF" 3 	 Raise up slightly off the seat Seat light (Item 1) [AJ should be "OFF" NOTE: Record what lights are blinking (if any) and number of blinks Refer to Page 63 4 Exit the 	loader and press traction lock override button Traction light (Item 4) [AJ should be "ON" Press override button again and traction light (Item 4) [AJ should be "OFF" Inspecting the Seat and Seat Bar Sensors (Engine RUNNING) 5 Sit 	in the operator's seat, lower the seat bar and engage the parking brake Fasten the seat belt 6 Start the engine and operate at low idle While raising the lift arms, raise the seat bar fully The lift arms should stop Repeat using the tilt function NOTE: 	The auxiliary hydraulic functions are not affected by the Bobcat Interlock Control System (BICS) Inspecting the Traction Lock (Engine RUNNING) 7 	 Fasten the seat belt, disengage the parking brake, and raise the seat bar fully Move the steering levers slowly forward and backward The traction lock should be engaged Lower the seat bar 8 	 Engage the parking brake pedal and move the steering levers slowly forward and backward The traction lock should be engaged Inspecting the Lift Arm By-Pass Control 9 Raise the lift arms six (6) feet (2 m) off the ground Stop the engine, pull and hold the by-pass control knob Push the "toe" of the left foot pedal and the lift arms should lower slowly MC-2043 Maintenance Clean any debris, dirt or objects from under or behind the operator seat [BJ & [CJ The rear of the seat must move up and down A WARNING Clearance is necessary under the seat spring (Item 1) [CJ and the seat, to allow the seat to move up and down freely With adequate clearance, the seat sensor will be allowed AVOID INJURY OR DEATH to function properly The Bobcat Interlock Control System (BICS) must deactivate the lift, tilt and traction drive Inspect seat bar pivot area for tightness of linkage bolts functions If it does not, contact your dealer for service DO NOT modify the system Replace parts that are damaged Use only genuine W-2151-0394 Melroe replacement parts '-/ 6 Melroe Company will give the following warranty compensation for labor to install the new check valves r--- 	Model 450 & 453 loaders Three quarter (314) hour Model 553 loaders One (1) hour All 700 series loaders One (1) hour Model 853 loaders One and one half (1-112) hours Model 873 loaders Two and one half (2-112) hours One (1) additional hour is allowed for travel time for retailed machines When filing warranty claims electronically use the following service codes determined by model: 400 Series 04R17 500 Series 05R33 700 Series 07R70 800 Series 08R63 DOMESTIC LOADERS 450 SIN'S 561711257, 11259, 11260, 11266, 11269-11347, 11349-11351, 11353, 11355, 11356, 11358, 11359, 11361 & 11362 453 SIN'S 561811152-11154, 11161-11235, 11237, 11239-11245, 11247-11252, 11255 & 11281-11289 553 SIN'S 513011560, 11565-11574, 11578, 11580-11584, 11586, 11587, 11589, 11590, 11592, 11594-11800, 11802-11805 & 11808 751SIN'S514711001-11193, 11195-11324, 11326-11368, 11370-11373, 11375 & 11376 753 SIN'S 512721665-23774, 23777-23796, 23798-23830, 23832-23868, 23870, 23871 , 2387 4-23877 & 23882-23888 763 SIN'S 512214789-16058, 16060-16128, 16130-16137, 16139-16156, 16158-16161, 16163-16166, 16168, 16169, 16172-16178, 16184 & 16186 773 SIN'S 509637363-38155, 38157-38176, 38178-38181 , 38184-38186, 38189 & 38191­38195 853 SIN'S 512819171-19834, 19836-20187, 20189-20483, 20485-20496, 20498-20506, 20508-20516, 20519, 20521-20524, 20526-20530,20532-20542,20544-20545, 20547-20551, 20554-20560, 20563, 20565-20567 & 20569 873 SIN'S 514111098, 11100-11339 & 11342 EUROPEAN LOADERS 450 SIN'S 562011049-11056 & 11059-11068 453 SIN'S 561911333, 11338-11344, 11346-11356, 11358-11390, 11396, 11398, 11400­11414, 11416, 11418-11449, 11451-11459 & 11463 553 SIN'S 513031641-31666 & 31668-31902 751 SIN'S 514911001-514911004 7530 SIN'S 508693836, 93842-93993, 93995, 93996 & 93998 7530H SIN'S 511476336-76340, 76343-76418 & 76420 753E SIN'S 508630546-30975, 30977, 30982, 30983, 30985 & 30986 763E SIN'S 512440327-40338 7630H SIN'S 512612001-512612002 773 SIN'S 509616265-16267 & 16269-16301 8530 SIN'S 508418103-18212 8530H SIN'S 509718133-18227 & 18229 873 SIN'S 514211015-11069 7 DIRECT TO: BOBCAT@ 	/ / / D D D D DATE: 6 October 1995 MODEL: 607, 709, & 811 BACKHOE SUBJECT: BACKHOE SWING CIRCUIT RESTRICTORS Swing circuit hoses installed in backhoe models 607, 709, and 811 have recently been replaced with end fittings requiring a restrictor with a larger outside diameter Some hose installations may have inadvertently received a restrictor with a smaller outside diameter This may allow the restrictor located between the hose and cylinder fittings to shift out of place This shifting condition could cause fluctuating boom swing speeds between each boom swing cycle To remedy a shifting restrictor condition, order and install the larger outside diameter restrictor from Melroe Parts Sales Each backhoe model requires two restrictors I 1 Tv  )estricto Here Restrictor part numbers are on the reverse side Printed in USA Determine the appropriate large outside diameter restrictor for your model as follows: BACKHOE 607 LARGE 00 RESTRICTOR PART NUMBER--6592864 OUTSIDE DIAMETER-550" (1397mm) ORIFICE SIZE--077" (196mm) BACKHOE 709 LARGE 00 RESTRICTOR PART NUMBER-6592853 OUTSIDE DIAMETER--550" (1397mm) ORIFICE SIZE ---090" (229mm) BACKHOE 811 LARGE 00 RESTRICTOR PART NUMBER--6592824 OUTSIDE DIAMETER--550" (1397mm) ORIFICE SIZE -107" (273mm) Determine the appropriate small outside diameter restrictor for your model as follows: BACKHOE 607 SMALL OD RESTRICTOR PART NUMBER---6587339 OUTSIDE DIAMETER-420" (1066mm) ORIFICE SIZE-077" (196mm) BACKHOE 709 SMALL OD RESTRICTOR PART NUMBER---6587338 OUTSIDE DIAMETER--420" (1066mm) ORIFICE SIZE --090" (229mm) BACKHOE 811 SMALL OD RESTRICTOR PART NUMBER--6569312 OUTSIDE DIAMETER--420" (1066mm) ORIFICE SIZE ---107" (273mm)  Normal warranty policy applies 2 BOBCAT@ DIRECT TO: / / / 0 0 0 DATE: 8November1995 MODEL: 450 SUBJECT: ENGINE FUSE AND FUSE DECAL A 20 amp engine fuse replaced the 15 amp engine fuse on model 450 loaders shortly after production start up This was done to eliminate the potential for the 15 amp fuse blowing during high engine speeds and high current demand A decal (P/N 6709733) was developed to reflect this change, however, the decal was not immediately available and is not installed in many of these machines ,,,--,, 	Later, a new wire harness was developed to add separate alternator and engine circuits This change involved the engine harness changing back to a 15 amp fuse and adding a 25 amp alternator fuse A new decal (P/N 6709734) reflects this change If you are servicing a machine because the engine fuse is blown, inspect the fuse block (see page 2) to determine the appropriate fuse and fuse decal to install If the machine is equipped with an original style fuse block the engine fuse should be changed from 15 amp to 20 amp If the machine is equipped with a current style fuse block the engine fuse should be 15 amp Determine the correct fuse decal part number and ensure the correct decal is installed If the wrong decal is installed Order and install the correct decal The fuse block and decal are located on the inside of the left upright in the engine compartment Continued on the reverse side 4FUSEcxx· Printed in USA 1 The original and current style fuse blocks can be identified by the quantity of fuses in the fuse block (see photo) The photo shows the current style fuse block The current style fuse block has three fuses (engine, BIGS and alternator) The correct decal is (P/N 6709734 ) The engine fuse is 15 amp (P/N 6707621 ) CURRENT STYLE DECAL (P/N 6709734) The original style fuse block has two fuses (engine and BIGS) The PWM and BOSS fuse locations shown on the decal are not available The correct decal is (P/N 6709733) The engine fuse is 20 amp (P/N 6707622) ORIGINAL STYLE DECAL (P/N 6709733)  Normal warranty policy applies 2 DIRECT TO: BOBCAT@ 	/ / / D D D DATE: 10November1995 MODEL: 853 AND 873 SUBJECT: HYDROSTATIC PUMP REPLACEMENT CONTROL SLEEVE ( A service replacement control sleeve is now available for model 853 and 873 loaders The control sleeve is located in each hydrostatic pump The new sleeve has the 0-ring relocated down approximately 050 inches This allows the 0-ring to seal on a new location in the bore An external sealing washer is used with this new sleeve to help prevent external contaminants from reaching the 0-rings If you have serviced the control sleeve with new seals and the control spool continues to leak, we recommend installing the new sleeve and seals We recommend installing this new sleeve only if the original sleeve leaks after new seals are installed Continued on the reverse side SLEEVED<X" Printed in USA 1 To install the new control sleeve order the following parts from Melroe Parts Sales This list of parts is for one hydrostatic pump section Order two sets of parts for a complete pump Refer to the loader service manual for the control sleeve removal and replacement procedure P/N Description Qty Ref 6667897 Control sleeve 1 A 6631471 Sealing washer 1 B 25K-20020 0-ring 2 c 6631449 Back-up ring 1 D B  ·';:;, ' ' P-7341 Install the sleeve and seals as shown Always check for proper machine neutral adjustment after control spool replacement Adjust if necessary Refer to the loader service manual for the adjustment procedure Normal warranty policy applies 2 BOBCAT@ DIRECT TO: / / / D D D DATE: 15November1995 MODEL: THREE POINT HITCH ATTACHMENT (P/N 6557905) SUBJECT: MISSING LINK MOUNTING BOLTS We have been made aware that two of the link mounting bolts have been missing on three point hitch attachments The correct number of mounting bolts and nuts are now being installed on current production attachments If you have received a three point hitch attachment that is missing two of the link mounting  	bolts and nuts, order and install the parts listed below Each link should have two mounting bolts and nuts The parts are available from Melroe Parts Sales Tighten the nuts to 65-70 ft-lbs torque PIN Description Qty Ref 38C-1028 Bolt 2 A 850-8 Nut 2 B Do not install the links using standard hardware The correct bolt (P/N 38C­1028) is a shoulder bolt If standard hardware is used the mounting holes may deform causing damage to the rear mounting holes  Normal warranty policy applies JPTIITTCHDOC Printed in USA 1 BOBCAT@ DIRECT TO: v' v' v' D D D DATE: 14December1995 MODEL: 853 AND 873 SUBJECT: HYDROSTATIC PUMP REPLACEMENT CONTROL SLEEVE This Service Letter replaces Service Letter dated 10 November 1995 The part number for the back-up ring on page 2 should be (P/N 6631468) A service replacement control sleeve is now available for model 853 and 873 loaders The control sleeve is located in each hydrostatic pump The new sleeve has the 0-ring  	relocated down approximately 050 inches This allows the 0-ring to seal on a new location in the bore An external sealing washer is used with this new sleeve to help prevent external contaminants from reaching the 0-rings If you have serviced the control sleeve with new seals and the control spool continues to leak, we recommend installing the new sleeve and seals We recommend installing this new sleeve only if the original sleeve leaks after new seals are installed / Continued on the reverse side s11:rv1::?l>(J<" Printed in USA 1 To install the new control sleeve order the following parts from Melroe Parts Sales This list of parts is for one hydrostatic pump section Order two sets of parts for a complete pump Refer to the loader service manual for the control sleeve removal and replacement procedure P/N DescriRtion Qt)l Ref 6667897 Control sleeve 1 A 6631471 Sealing washer 1 B 25K-20020 0-ring 2 c 6631468 Back-up ring 1 D B P-7341 Install the sleeve and seals as shown Always check for proper machine neutral adjustment after control spool replacement Adjust if necessary Refer to the loader service manual for the adjustment procedure Normal warranty policy applies 2 DIRECT TO: BOBCAT@ 	/ / / Servic-eletter D D D DATE: 	12December1995 MODEL: 	PLANER (REXROTH MOTOR ONLY) L T405 TRENCHER SUBJECT: INNER SHAFT SEAL REPLACEMENT We are aware that two types of inner shaft seals have been installed in the motor used in the planer and L T405 trencher attachments which are equipped with a Rexroth motor One seal is a lip type and the other is a quad ring type seal We recommend only using the quad ring type seal whenever installing new seals · Motor seal kit (P/N 6660788) contains only the quad ring type seal If the motor being serviced is equipped with a lip type seal, a new seal holder ring (P/N 6660014) is required to install the quad ring seal The seal holder ring is available from Melroe Parts Sales P-0126 Continued on the Reverse side RlXSlAl:!D(X Printed in USA 1 Cross section drawing of motor showing both seal types used  Normal warranty policy applies 2 DIRECT TO: CK"" BOBCAT® CK"" CK""  0 0 0 DATE: 1 November 1994 0 MODEL: 853 C SERIES SUBJECT: REQUIRED MODIFICATION OF BELT TENSION TOOL MEL1404 Belt tension tool MEL 1404 is used to check drive belt tension in all model 853 loaders We are aware that tilt cylinder tubelines interfere with access when positioning the tool in the new 853 C series loaders To provide easier installation the following simple modification (for additional clearance) must be performed on MEL 1404 before use Grind material from the end of the tool to obtain the shape shown This will provide needed clearance for tool installation and removal The tubelines can be adjusted upwards to provide additional clearance  	The affected tubelines will be changed on future 853 C series machines Printed in USA DIRECT TO: BOBCAT® 	[]" []" []"" 0 0 0 DATE: 2 November 1994 0 SUBJECT: BOB-TACH MOUNTING BRACKET We are making a change to the Bob-Tach mounting bracket on all attachments The locating holes for the Bob-Tach wedges will be revised for improved fit with the current production Bob-Tach The extra inner set of holes has been eliminated The extra set of holes was for use with some earlier production model loaders All attachments will now have one set of mounting holes for the Bob-Tach wedges These holes are· relocated and widened by 140 inch This provides improved attachment mounting This change will be phased in Eventually all attachments will have one set of mounting holes All new attachments will require modification before installing onto most of the following model loaders: 444, 500, 520, 600, 610, 611 , 620, 700, 720, 721, 722 and 825 To determine if the attachment requires modification, measure the distance between the wedges on the loaders Bob-Tach If the distance from wedge center to wedge center is 295 inches (7493 mm) the attachment will require modification Continued on the reverse side Printed in USA To modify an attachment, remove material from the inside edge of each locating hole on the attachment as shown Check for proper fit with the Bob-Tach / / MC2094   ,; DIRECT TO: BOBCAT® cY  cY cY D D D D DATE: 9November1994 MODEL: 553 753, 763, 773, 853 (with BICS™) SUBJECT: GRAMMER SEAT MOUNTING KIT (P/N 6708523) The model loaders listed above use the non-suspension Milsco seat as standard equipment Grammer suspension seat option 6707764 is available as listed in the sales handbook The installation of the optional Grammer suspension seat has been changed in current production loaders This change relocates the seat sensor and spring This provides improved operation of the seat sensor with the Grammer suspension seat A kit (P/N 6708523) has been developed for use with the Grammer suspension seat installed in SICS equipped loaders If you have received one of the following loaders equipped with an optional Grammer suspension seat, we ask you to order and install this kit: 753 (S/N 512717184 & Below), 763 (S/N 512212487 & Below), and 773 (S/N 509635487 & Below) Order kit (P/N 6708523) from Melroe Parts Sales Installation time is approximately two hours Installation instructions (P/N 6724161) are included This kit is not for use with the standard seat or Milsco suspension seat If you have ordered a Grammer suspension seat from Melroe Parts Sales also order and install this kit Order this kit with all future orders for the Grammer suspension seat from Melroe Parts Sales  Normal warranty policy applies Printed in USA DIRECT TO : BOBCAT® W  lY lY D D D D DATE: 14November1994 MODEL: WS18 AND WS12 WHEEL SAW ATTACHMENTS SUBJECT: WHEEL MOUNTING BOLT TORQUE REQUIREMENTS The specification for wheel mounting bolt torque has changed The mounting bolts must be checked for correct torque after the first 2-3 hours of operation The previous specification required rechecking torque after 5 hours operation If the wheel mounting bolts have been removed for any reason, recheck mounting torque again after the first 2-3 hours of operation The correct mounting torque is 190-200 ft-lbs (260-271 Nm) Printed in USA DIRECT TO: BOBCAT® 	c::Y' c::Y' c::Y' 0 0 0 FIELD MODIFICATION 0 DATE: 15November1994 MODEL: 325 EXCAVATOR SIN'S (511820123 -511820625) (STEEL TRACK ONLY) 331 EXCAVATOR SIN'S (511920153 -512911176) (STEEL TRACK ONLY) SUBJECT: TRACK RECOIL SPRING ASSEMBLY SPACERS We are aware that some model 325 and 331 excavators may have the incorrect track recoil spring assemblies installed This only affects units that are in the range of serial numbers listed above and are equipped from the factory with steel tracks The correct track recoil spring assembly does not have spacers Dealers are asked to inspect both recoil spring assemblies (one on each side) on the affected machines listed above If spacers are present, remove the spacers as described on the reverse side Failure to remove the spacers may cause damage to the tracks Continued on the reverse side Printed in USA Follow the procedure in the service manual section 5 to remove the recoil spring assembly NOTE: To simplify removal, bleed the grease cylinder, then remove one track link connecting pin from the front of the idler wheel This allows you to separate the track and remove the idler wheel and recoil spring assembly without removing the entire track Remove the recoil spring assembly Remove the adjusting nut and both spacers NOTE: Use caution when removing the nut It is under spring tension Position the spring assembly in a press to remove the nut Adjusting Nut B-14049 Apply thread sealant LocTite 242 or equivalent to the adjusting nut Adjust the spring to 9110" (2315 mm) It may be necessary to install the spring assembly into a press and compress the spring slightly to start the adjusting nut Re-install the recoil spring assembly and track Adjust track tension L9110" J Repeat this procedure for the other side (2315 mm) B-14 159 Melroe Company will give compensation for four (4) hours labor to remove the recoil spring spacers as described above DIRECT TO: BOBCAT® cY  0 0 0 0 DATE: 	16 November 1994 MODEL: 	331 EXCAVATOR (S/N 511920461 -Approximately 512911140) WITH CABS ONLY SUBJECT: 	FRESH AIR FILTER REMOVAL Model 331 excavators S/N 511920461 & above are equipped with a fresh air filter in the operator cab We are aware that the air filter element may be difficult to remove for cleaning Some machines have cab insulation directly above the filter This insulation has been removed on current production machines If you receive a complaint regarding cab filter element removal, remove the cab insulation as described below Loosen the heater assembly mounting screws as required to gain access for insulation removal Remove the insulation from the cab wall directly above the filter element Make two cuts, one on each side of the element holder Use a knife and straight edge for a neat cut Remove the insulation all the way up to the window Clean the cab surface in the area that foam was removed Lacquer thinner may be used Use caution with flammable cleaners Continued on the reverse side Printed in USA The filter element is cleaned by using compressed air and blowing the contaminates backward through the filter Do not wash the filter element Washing the filter reduces filter element life  Normal warranty policy applies DIRECT TO: cY BOBCAT® cY cY  D D D D DATE: 6 December 1994 MODEL: 753, 763, 773 SUBJECT: IMPROVED DRIVE BELT IDLER BRACKET A new drive belt idler bracket is now installed in the above listed loaders starting in early December 1994 It is now available from Melroe Parts Sales This idler bracket is a result of a team effort to improve the service life of this part After considerable hours of design, testing and in field service, we feel we have developed a superior bracket If bracket replacement is required , install this new bracket Do not continue to install the earlier brackets The bracket is available as a separate part (P/N 6707414) for individual bracket replacement A complete idler assembly with the new bracket is also available as (P/N 6708376) Both are available from Melroe Parts Sales The new bracket is a ductile cast design Earlier designs were a shaft welded to a back plate Identify the new bracket by this one piece cast See photo  Normal warranty policy applies Printed in USA DIRECT TO: rY BOBCAT® LY cY  D D DATE: 9December1994 SUBJECT: PROPYLENE GLYCOL ANTIFREEZE Effective January 1995 all liquid cooled loaders and excavators will be changed from ethylene glycol antifreeze to propylene glycol antifreeze Propylene glycol is environmentally safer while providing equivalent or superior performance Machines using propylene glycol antifreeze will be equipped with a new decal (P/N 6708929) This decal informs owners to fill with propylene glycol when required Owners and Service manuals will be revised Some significant differences exist between ethylene glycol and propylene glycol You must be aware of these differences to properly service cooling systems Propylene glycol is mixed with water to provide the proper concentration level The recommended ratio is 53% propylene glycol and 47% water This will provide freeze protection to -34 ° F Correct propylene glycol mixture ratio can not be tested with a OEM 1044 hydrometer (floating balls) A refractometer is recommended A refractometer is available from Owatonna Tool Company as OEM 1044 This refractometer has a scale for reading propylene glycol and a scale for reading ethylene glycol When using a refractometer you must know if the mixture is propylene glycol or ethylene glycol If the system contains a mixture of propylene glycol and ethylene glycol split the difference between the two scales or use the propylene glycol scale Ethylene glycol and propylene glycol can be intermixed, however, this practice is not recommended Propylene glycol is available from Melroe Parts Sales It is supplied in one gallon containers as (P/N 6724094) It is premixed at the recommended 53/47 ratio to provide protection to ­34° F Propylene glycol installed in new machines and from Melroe Parts Sales is colored purple for identification Printed in USA DIRECT TO: BOBCAT® cY cY -/ cY  D D D D DATE: 16 February 1994 SUBJECT: TAPERED REAMER SHARPENING SERVICE A new service is offered by OTC (Owatonna Tools Company) OTC will sharpen tapered reamers part number MEL-1233 and MEL-1195 These reamers are used to refurbish the tapered holes in the lift arms for the bobtach mounting pins For sharpening of reamers MEL-1233 or MEL-1195, send them to: OTC 655 Eisenhower Drive Owatonna, MN 55060 Attn: Customer Return Department You MUST indicate that the reason for return is to sharpen the reamer They will sharpen the reamer(s) and return it to you The charge is $4500 per reamer plus the cost of return shipping They will sharpen reamers every other week so the turn around time may vary If the reamer is damaged or can not be sharpened properly, the reamer will be returned to you and you will be invoiced for the return shipping charges Printed in USA DIRECT TO: BOBCAT® Dr"" cY Dr"" D D D D DATE: 18 February 1994 SUBJECT: FOAM INSULATION REPAIR SYSTEM A new foam insulation repair system is now available from Melroe Parts Sales This system allows you to repair loose cab headliners, foam in engine compartments and other glued on foam used on Melroe products This system uses a glued on base and plastic retainer Bases, retainers and Installation Instructions are available in a kit Special adhesive and activator are required for installation of the bases The bases and retainers are also available separately The part numbers of each item are listed below Follow the installation instructions provided in the kit Foam insulation kit (P/N 6722862): P/N Description Oty 6664896 Base 12 6664897 Retainer 12 6722904 Instructions 1 Order Speed Bonder and Activator separately: Speed Bonder (P/N 6722902) 17 fluid oz Activator (P/N 6722903) 6 fluid oz Printed in USA BOBCAT® DATE: 28 February 1994 MODEL: 7753 SUBJECT: ADJUSTING CLEARANCE ADJUSTMENT HANDLE FOR OPERATORS SEAT A modification to the operator seat adjustment lever (Item 1) is necessary for all model 7753 loaders (S/N 30945 & Below) ,--  	All model 7753 loaders which have had the Lift Control System-FielG--Medificatieri K-it:s-(P/N-9-70-7-GBg,6 7 07 08-, 6707090 and 6707091) already installed, require this adjustment Also make this adjustment to all model 7753 loaders during the installation procedure of the Lift Control System Field Modification Kits When 	adjusting the operator seat forward, the adjustment lever (Item 1) interferes with the lift arm by-pass 	control knob (Item 2) Use the following procedure to modify the position of the seat adjustment lever on all standard operator seats: NOTE: 	Loaders with optional suspension operator seats also need to be adjusted to prevent interference between the seat adjustment lever and the by-pass control knob The adjustment lever on the optional suspension seat is longer than levers on standard operator seats Pull up on the adjustment lever to eliminate any interference with the by-pass control knob Adjusting Standard Operator Seat Adjustment Lever Raise the loader operator cab until the cab rests S!'lcurely on the cab latching mechanism (Refer to the 7753 loader Service Manual for the correct procedure) Push the operator seat adjustment lever (Item 1) and pull the seat forward as far as possible 00 DIRECT TO: cY cY cY D D D D Printed in USA Place a 7/8" (22 mm) diameter pry bar (Item 1) on top of the seat adjustment lever bracket NOTE: 	Be sure to keep the pry bar held tightly against the metal on the bottom portion of the seat Keeping the pry bar tight against the seat allows the seat adjustment lever bracket to bend properly Be sure the bracket is bending and not the lever The adjustment lever will break if the lever only is being bent Place the box end of a 9/16" wrench over the operator seat adjustment lever Bend the seat adjustment lever bracket until the end of lever is 3/4" (19 mm) from the bottom of the seat edge [i] Slide the operators seat back and forth to various positions and make sure the seat lock operates properly , DIRECT TO: BOBCAT® W W W D D D D DATE: 8 March 1994 MODEL: 753, 7753, 645, 7438(18000 & Above) & 7428(18000 & Above) SUBJECT: NEW MOTOR CARRIER SHAFT SEAL (P/N 6705847) The models listed above have a motor carrier which transfers the rotary motion of the motor to a sprocket which drives the chains A new shaft seal is now installed in the motor carriers The new seal is a one piece design This design offers easier installation and increased service life The new seal is now the service replacement for all machines listed above A new seal installation tool MEL-1420 is required for installation This tool is available from OTC NQTE: No 0-rings are used with this seal New one piece seal (P/N 6705847) New seal installation tool MEL-1420  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® Dr" cY Dr""  D D D DATE: 11 March 1994 D MODEL: 220 EXCAVATOR (S/N 11501 & Above) 320 EXCAVATOR (S/N 20661 & Below) SUBJECT: SWIVEL JOINT MOUNTING The mounting of the swivel joint has been changed The four mounting bolts (Item 1) are now installed with Loctite 242 or equivalent A nut (Item 2) (P/N 1 DM-8) is installed above the weld nut on each bolt and tightened The addition of this nut provides a more secure installation If you are servicing an excavator listed above for a loose swivel joint mounting, check for these nuts If there are none, install the swivel joint as described above If servicing a machine with these nuts in place, remember to remove them before removing the bolts from the weld nuts 1DM-8 I I ©-! I 8-14102 NOTE: This letter does not apply to 320 excavators (S/N 20662 & Above) These machines use a different swivel joint and mounting hardware This is provided as technical information Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® []/""" cY cY D D D D DATE: 	14 March 1994 MODEL: 	542B ALL 543B (S/N 11525 & Below) 543 (S/N 26550 & Below) SUBJECT: 	HYDROSTATIC PUMP REPLENISHING AND REPLENISHING/RELIEF VALVE LOCATION We are aware that some hydrostatic pumps in the models listed above may have the replenishing valves and the replenishing/high pressure relief valves installed in the wrong locations The serial numbers listed are approximate This condition has been ?--corrected in current production machines / This is provided as technical information NO field modification is planned In the -· event a hydrostatic pump is overhauled, it is recommended that the replenishing valve be installed in the correct location The following diagram shows the valves incorrectly and correctly installed Correct location 	Incorrect location Printed in USA DIRECT TO: cY BOBCAT® cY cY  D D D D DATE: 8 April 1994 MODEL: 225 Excavator (S/N 11001 -13043) SUBJECT: TRACK DERAILING This service letter replaces service letter dated 20 October 1993 A new kit (P/N 6722969) with new parts and instructions has been developed If a model 225 excavator (S/N 11001-13043) experiences repeat track derailing, a new kit (P/N 6722969) is available to correct this condition This kit contains new rollers with an added center rib to better guide the track Spacers are added to the grease cylinder to improve tension on the track This kit is available from Melroe Parts Sales Estimated installation time is five hours Kit (P/N 6722969) includes the following parts: P/N DESCRIPTION QTY REF NOTE: If new spacers P/N 6589053 and 6722968 Track roller 6 A 6589143 have been installed previously, 6589053 Spacer 2 B then it is not necessary to add the 6589143 Spacer 2 c spacers which come with the kit 6722970 Instructions Continued on the reverse side Printed in USA (P/N 6722968) NEW double "V" groove roller (P/N 6534244) OLD Single "V" groove roller  Normal warranty policy applies I I I I DIRECT TO: BOBCAT® Cll""" Cll""" cY D D D DATE: 6 April 1994 D MODEL: 325 EXCAVATOR SUBJECT: TRACK DERAILING Current production 325 excavators are equipped with a track frame with idlers and rollers that can accommodate either rubber or steel tracks If the excavator is equipped with rubber tracks and repeat track derailing occurs, a kit (P/N 6722936) is available to correct this condition This kit contains idlers and rollers that have a larger center rib to better guide the track Spacers are added to the grease cylinders to improve tension on the tracks This kit is available from Melroe Parts Sales Installation time is approximately five hours Kit (P/N 6722936) includes the following parts: P/N DESCRIPTION 6588999 Front idler 6589006 Track roller Refer to parts 6589054 Spacer 6589143 Spacer 6589129 Decal 6722937 Instructions  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® c:Y W W D D D D DATE: 7 April 1994 MODEL: 	853 STANDARD (S/N 512811001 -512811883) 853 Base (S/N 510126792 & Above) 853 Plus (S/N 510250692 & Above) 853 Deluxe (S/N 508415216-508415311) SUBJECT: 	AUXILIARY HYDRAULIC CIRCUIT CHANGE FOR OPTIONAL AUXILIARY PORT RELIEF The auxiliary hydraulic circuit in current production 853 loaders has been changed We have determined that in the machines listed above, the optional auxiliary port relief valve is not in the proper circuit Do to this, high pressure protection for the attachment cylinder in machines using the grapple or combination bucket attachment does not exist When performing scheduled service on machines listed above, we recommend reversing the auxiliary hydraulic circuit as described below It is important to perform this procedure in those affected machines which are known to be operating with grapple or combination bucket attachments This does not affect the normal operation of the machine The following procedure reverses the outlet ports of the auxiliary hydraulic circuit The procedure can be performed in less than one-half (1/2) hour Raise the operator cab Follow the procedure in the Service Manual Reverse the electrical connections at the hydraulic control valve auxiliary solenoids Lower and secure the operator cab Continued on the reverse side Printed in USA Reverse the hydraulic hose connections in the auxiliary hydraulic circuit  I ,-' 1Male : Coupler 'J I Female I Coupler I I I I I I ' I I /, / / aA   rf:::ii I I ,,! ,,"' /'V Q I I / I //--/ I I / To Hydraulic ,,,/ I · / Control Valve !­ ,, / '-(Auxiliary Spool) ,, "' Male Coupler To v This Fitting  Normal warranty policy applies DIRECT TO: V BOBCAT® V -v DATE: 15 April 1994 SUBJECT: LOW SULFUR FUEL The new US Environmental Protection Agency regulations requmng low sulfur diesel fuel for on highway use went into effect on October 1, 1993 The regulation restricts sulfur content to less than 05% by volume This is reduced from the 5% by volume maximum which is now allowed for off highway use only The aromatics are also limited to 35% and in California limited to 10% Hydroprocessing is the refining process used to remove sulfur and aromatics from the fuel A positive result of this is that the reduced sulfur decreases the acids formed in the engine combustion chambers which can help extend engine life The disadvantages are the reduction of aromatics in the fuel may result in lower lubricity of fuel and potential problems with seals 1 Lower fuel lubricity No current standards for lubricity exist, therefore fuel lubricity may vary with suppliers Rotary type fuel pumps seem to be the most affected by this condition We use rotary pumps on the Isuzu and Perkins engines Plunger style fuel injection pumps as used on Kubota engines are typically not affected Because processes and quality vary with suppliers, a fuel additive (P/N 6663957) which increases lubricity may be good insurance against premature wear, especially in the rotary type fuel injection systems 2 Seal leakage Nitrile (Buna N) seals have a tendency to draw the aromatics out of the fuel causing the seals to swell When the new low sulfur fuel with less aromatics is used the aromatics tend to leach back into the fuel causing the seals to shrink This stress on the seals can cause the seals to crack The seal problem is mostly with dynamic type seals and on the older seals that may have been in the swelled condition for a long time The Kubota fuel system does not have dynamic seals, therefore we expect·no problems Seals made from viton material are not affected by the aromatics in the fuel To avoid these concerns we recommend continued use of the off highway fuel (with blue dye) If this fuel is not available locally a fuel additive may be beneficial Customers and dealers should address these concerns directly with their fuel supplier Fuel conditioner (P/N 6663957) is available from Melroe Parts Sales  Melroe Company DOES NOT warranty damage to engines or engine components due to low lubricity diesel fuels Printed in USA DIRECT TO: cY BOBCAT ® cY W  D D D DATE: 18 April 1994 D MODEL: 5428, 5438, 753, 7753 and 853 LOADERS SUBJECT: NEW 808-TACH MOUNTING PIN KIT A new Bob-Tach mounting pin and bolt are now available The new pin has a hollow center The mounting threads are at the base end of the pin This design provides improved torque retention of the 8ob-Tach pin A new mounting bolt is required with this pin This new pin (P/N 6707042) and bolt (P/N 17C-1064) are a direct replacement for the existing pin (P/N 6700301) and bolt (P/N 17C-1028) For your convenience a kit (P/N 6707521) is available from Melroe Parts Sales (to do both sides you must order two kits) The kit includes installation instructions (P/N 6722967) Reuse the existing washer or order replacement washer (P/N 6555455) If you have an existing stock of 8ob-Tach pins (P/N 6700301) and/or bolts (P/N 17C­1028) we recommend installing these in model 5428 and 5438 loaders only If you have a limited amount of 500 size loaders in your area you may return your stock to Melroe Parts Sales in Chicago for credit as part of your dealer annual parts return ·  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® c::Y'  c::Y' c::Y' D D D D DATE: 19 April 1994 MODEL: 2500 AND 3500 HYDRAULIC BREAKERS SUBJECT: SEAL SERVICE PROCEDURE New seals are now installed in model 2500 and 3500 hydraulic breakers The new seals are a Disogrin brand seal The Disogrin seals provide extended seal life Cross hatches are added to the hammer piston to allow the Disogrin seals to be used Important seal installation procedures are provided below The hydraulic breaker service manual (P/N 6720280) will be revised to include installation of the new seals Follow the hydraulic breaker service manual for general service procedures The seals affected are the lower bearing inner seal (item 1) and the lower housing wiper seal (item 2) (see diagram) caJ-Lower Bearing Original hammer pistons were polished for use with earlier seals When using the Disogrin seals the hammer pistons Cross Hatch ! are cross hatched in the sealing area / The cross hatch pattern helps trap oil to lubricate the Disogrin seals -Lower Housing The Disogrin seals and cross hatched hammer pistons are installed at the following serial numbers: 2500 Hydraulic breaker (S/N 896706461 & Above) and (S/N 705200199 & Above) 3500 Hydraulic breaker (S/N 897200816 & Above) and (S/N 705400144 & Above) All units below these serial numbers used poly-pak seals and polished  hammer pistons j" Continued on the reverse side Printed in USA 2500 and 3500 hammer piston seal installation procedure: NOTE: The seal kit (P/N 6660116) includes poly-pak seals and Disogrin seals We recommend installing the Disogrin seals as described below The approximate seal lD is provided to help identify the correct seal Do not measure on the seal lip Inspect the hammer piston seal area for a cross hatch pattern If there is no cross hatch pattern (polished piston) apply a new cross hatch pattern If there is a cross hatch pattern and it is partially worn smooth, apply a new cross hatch pattern To apply a cross hatch pattern, place the hammer piston on a work bench and hold it in an upright position Use Scotch Brite or emery cloth and move it up and down in the area shown while rotating the hammer This will produce very fine surface scratching in a cross hatched pattern Hammer Piston -  Cross Hatch This Area Only 2500 hydraulic breaker: Lower housing wiper seal: Discard the original (orange or cream) colored seal Install the new 2110" cream (Disogrin) seal NOTE: Some earlier kits do not have a 2110" cream seal, install the 2110" orange seal in its place Lower bearing inner seal: Discard the original (yellow or cream) seal Install the new 2140" cream (Disogrin) seal in its place Continued 3500 hydraulic breaker only: Lower housing wiper seal: Discard the original (gray, spacer & black or cream) colored seal Install the new 2050" cream (Disogrin) seal NOTE: Some earlier kits do not have a 2050" cream (Disogrin) seal, install the spacer and new 2040" black seal in its place (spacer first) Lower bearing inner seal: Discard the original (cream or gray) seal Install the 2020" cream colored (Disogrin) seal in its place NOTE: Only cross hatched hammer pistons may be used with the Disogrin seals and only polished hammer pistons may be used with the poly-pak seals Inter-mixing of these parts will result in premature seal failure DIRECT TO: BOBCAT® 	[]t"" []t"" ur"' 0 0 0 0 DATE: 	10May1994 MODEL: 	320 EXCAVATOR (S/N 20662 & Above) 325 EXCAVATOR (S/N 20179 & Above) 331 EXCAVATOR (S/N 20098 & Above) SUBJECT: 	NEW SWIVEL JOINTS A new swivel joint is now installed in model 320, 325 and 331 excavators starting at the serial numbers listed above The new swivel joint offers many quality improvements The torque required to rotate the rotor end is approximately 50% less The seal design is also improved providing longer seal life NOTE: A welded pin is used in place of the stop bolt (C) for model 220 and 320 If servicing the swivel joint in an earlier 200 or 300 series excavator, be observant for the following items: CONDITION 	RESULT REF Low seal life Repeat seal replacement A Worn or scored internal parts Part replacement B Broken stop bolt Hose damage, part replacement C Loose/broken mounting Hose damage D Continued on the reverse side Printed in USA If repeat failures of the swivel joint or mounting occurs in earlier models, installation of the new swivel joint should be considered The following BTl's are being produced and will be sent to s when complete They will provide detailed information for swivel joint replacement BTI MODEL E-029 220 (S/N 11500 & Below) E-032 220 (S/N 11501 & Above) E-028 225 (S/N 11001-11999) E-031 225 (S/N 12001 & Above) E-027 231(S/N11001-11999) E-026 231 (S/N 12001 & Above) E-026 331 (S/N 20001-20097) To be determined 320 (S/N 20001-20661) To be determined 325 (S/N 20001-20179)  Normal warranty policy applies BOBCAT® DATE: 12May1994 MODEL: 943, 974, 975 & 980 LOADERS 2410 & 1600 ARTICULATED LOADERS SUBJECT: VITON 0-RINGS DIRECT TO: Dr" Dr" Dr" D D D D The a-rings used in Melroe products are continually monitored for performance · Melroe products use special a-rings with carboxilated nitrile compound This material is more resistant to compression set Some time ago many a-rings were crossed from a 70 durometer nitrile a-ring (black) to 90 durometer nitrile a-rings (black) The 90 durometer a-rings reduced oil leaks 90 durometer a-rings are harder than the 70 durometer a-rings  	0-rings made from viton material (usually brown) are now available The viton material can withstand very high operating temperatures They are installed in many locations in those models listed above The following are part numbers for converting the older 70 durometer o­rings to the 90 durometer a-rings These are nitrile a-rings 70 	90 Durometer Durometer 91F-3 79K-4 91F-5 79K-6 91F-6 79K-8 91F-7 79K-10 91F-8 79K-12 91F-9 79K-14 91F-10 79K-16 91F-11 79K-20 If leaks are encountered with the 90 durometer nitrile a-rings you may install the equivalent viton a-ring in its place We find this most beneficial in face seal applications 90 Durometer Viton 58K-219 77K-219 58K-21 77K-21 79K-4 78K-04 79K-6 78K-06 79K-8 78K-08 79K-10 78K-10 79K-12 78K-12 79K-14 78K-14 79K-16 78K-16 79K-20 78K-20  Normal warranty policy applies Printed in USA DIRECT TO: []"""' BOBCAT® cY cY D D D DATE: 9 June 1994 D MODEL: 540 SERIES, 645, 7428, 7438, 753 SERIES and 7753 LOADERS SUBJECT: NEW 808-TACH MOUNTING PIN KIT NOTE: This Service Letter replaces Service Letter dated 18 April 1994 The models have been revised and serial number breaks are provided A new Bob-Tach mounting pin and bolt are now available The new pin has a hollow center The mounting threads are at the base end of the pin This design provides improved torque retention of the Bob-Tach pin A new mounting bolt is required with this pin Instructions (P/N 6722967)  )!(- Bolt (P/N 17C-1064) -INITftUCTIONS- -------·IGi:)] ------------ ·-­ ::= -1=---- 0 :-----·--­ -·--­ Pin '(P/N 6707042) C\@ Kit (P/N 6707521) This new pin (P/N 6707042) and bolt (P/N 17C-1064) are a direct replacement for the existing pin (P/N 6700301) and bolt (P/N 17C-1028) For your convenience a kit (P/N 6707521) is available from Melroe Parts Sales (to do both sides you must order two kits) The kit includes installation instructions (P/N 6722967), one pin (P/N 6707042) and one bolt (P/N 17C-1064) Reuse the existing washer or order replacement washer (P/N 6555455) Continued on the reverse side Printed in USA If you have an existing stock of 8ob-Tach pins (P/N 6700301) and/or bolts (P/N 17C­1028) we recommend installing these in model 540 series loaders only If you have a limited amount of 500 size loaders in your area you may return your stock to Melroe Parts Sales in Chicago for credit as part of your dealer annual parts return The new pin and bolt are installed starting with the following serial numbers 543 26831 & Above 5438 11946 & Above 645 11966 & Above 7428 19987 & Above 7 438 25808 & Above 753 512712377 & Above 7530 508691053 & Above 753DH 511475068 & Above 753L 512211005 & Above 7753 509614884 -509629999 7753 509631470 & Above  Normal warranty policy applies DIRECT TO: BOBCAT® W' ,,,/-\ W' W' 0 0 0 DATE: 21June1994 0 MODEL: LT204 TRENCHER ATTACHMENT (S/N 106 -283) EXCEPT SIN'S 278 & 281 SUBJECT: CHAIN TENSION GREASE CYLINDER INSTALLATION We are aware of a condition that may exist with the above listed L T204 trencher attachments If the attachment is assembled with the chain guide mounting bolts installed before the grease cylinder piston is extended, the chain guide mounting bolts will prevent extension of the grease cylinder piston This has the following effect: The end of the grease cylinder piston will press against the chain guide mounting bolts to maintain chain tension While the trencher is in service the chain guide mounting bolts may shear off This will loosen the chain When the operator applies more grease the piston will then extend past the broken bolts and tighten the chain The bolts (P/N 84G-3712) may require replacement Continued on the reverse side Printed in USA The factory assembly procedure is changed to correct this condition in machines serial number 284 & Above (also 278 & 281 ) The chain tensioning grease cylinder is extended with the chain guide mounting bolts removed After the chain is tensioned the chain guide mounting bolts are installed This ensures the chain tensioning piston is fully extended past the chain guide mounting bolts Dealer service departments should be aware of this condition If you have an attachment that you suspect may have this condition, we recommend simply removing the chain guide mounting bolts and setting correct chain tension After the chain is adjusted, install the chain guide mounting bolts This ensures the grease cylinder piston is fully extended past the chain guide mounting bolts  Normal warranty policy applies DIRECT TO: BOBCAT® cY  cY W D D D D DATE: 12 July 1994 MODEL: 	231 EXCAVATOR (12000) SERIES 331 EXCAVATOR SUBJECT: 	NEW SWING MOTOR RELIEF VALVE (6665480) NOTE: This Service Letter replaces Service Letter dated 15 December 1993 Remove and destroy the 15 December 1993 Service Letter An improved relief valve is now available from Melroe Parts Sales An improved swing relief valve is now available The new relief valve is (P/N 6665480) It is a direct replacement for the original relief valve (P/N 947639) and replacement valve (P/N 6664959) If replacement is required, we recommend using this new relief valve The pressure setting of this valve is 2066 psi which is the same as the valve it replaces Continued on the reverse side Printed in USA It is very likely that one of the swing motor relief valves requires replacement if one of the following symptoms is reported Both relief valves may require replacement if the symptoms are reported in both directions: 1 When the house is moved and the lever is released, the house does not stop quickly, and when operating on a slope the house has a tendency to drift in the down hill direction 2 When the house is moved and the lever is released, the swing relief valve makes a loud squealing or squawking sound Relief valve (P/N 6665480) can be identified by the numbers 32041-LA3 stamped on the end  Normal warranty policy applies / DIRECT TO: BOBCAT® 	 cY cY  D D D D DATE: 14 July 1994 MODEL: 325, 331, 231 & 225 EXCAVATORS SUBJECT: 2500 HYDRAULIC BREAKER MOUNTING PACK KIT (P/N 6722795) We have received reports of broken hydraulic breaker mounting pins This has occurred when the model 2500 hydraulic breaker is installed on model 325, 331, 231 or 225 excavators in heavy duty applications The mounting pin (P/N 6536163) fails at the cross drilled hole of the pin A kit is available for use in these applications This kit provides heavy side plates for increased pin support New solid mounting pins provide increased service life Grease fittings (supplied in the kit) must be installed in the arm and dipper for lubricating the solid  / 	pins We have found the installation of this kit greatly improves the service life of the mounting pins The kit is part number 6722795 It is available from Melroe Parts Sales The kit comes with installation instructions (P/N 6724030) Installation time is approximately one hour  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® cY  cY cY D D D FIELD MODIFICATION o DATE: 8 August 1994 MODEL: 853 SUBJECT: NON RETAILED DRIVE MOTOR REPLACEMENT We are aware of a process change in the manufacture of 853 drive motors This change has resulted in low hour motor failures The process has been corrected All current production machines and motors in stock in Melroe Parts Sales are manufactured with the correct process We have developed a drive motor return procedure which affects the following machines only: All non retailed machines prefix 5128 with the following serial numbers 11531-13035, 13037-13039, 13041, 13042, 13044-13047, 13049, 13052, 13057-13059, 13063, 1'3064, 13066, 13068, 13069, 13071, 13076, 13077, 13105, 13113-13116, 13118, 13121-13123, 13125, 13126, 13133, 13135 & 13140 All non retailed machines with motor date codes 11 94 through 27 94 If you have one of these non retailed machines, order two service replacement motors (P/N 6662313), 0-rings (P/N 25K-30508) & Bushings (P/N 6513681) from Melroe Parts Sales Motor kit (P/N 6722529) which consists of one each of the previous parts is not presently available, therefore order the parts separately You will then be contacted by Melroe Service for machine verification A warranty claim, motor return tags and return shipping labels will be sent to you Continued on the reverse side Printed in USA Inspect all removed drive motors to determine if further machine servk;e is required Disassemble the drive motors to remove the star and rollers Inspect the star; rollers an9 end plate for damage The first sign of damage will likely be a frosted appearance on the surface of the rollers and/or star Further damage will result in galling or other wear· of the rollers, star or end plate If the galling (remova·I of material) is significant, we then recommend removal, cleaning and inspection of the hydrostatic pump(s) I Roller Star P-3829 IMPORTANT: Affix the warranty parts tag (supplied) onto each returned motor Ship all motors removed from these non retailed machines directly to the manufacturer Use the return shipp·ing labe,1·provided Melroe ·company wilf ive warranty compensation for the cost of the motors and three and one-half (35) hours labor to remove, replace and inspect both drive motors Normal warranty policy will apply for hydrostatic pump service only if required as described above Shipping costs to the manufacturer will be reimbursed NOTE: This Service Letter applies for non retailed 853 loaders only 853 loaders that have been retailed or are in your dealer rental fleet will be handled under normal warranty policy Our experience with this indicates less than 10% will fail and most of these will be within the first 40 hours ­ DIRECT TO: BOBCAT® 	cY cY cY  D D D FIELD MODIFICATION D DATE: 8August1994 MODEL: 853 SUBJECT: NON RETAILED DRIVE MOTOR REPLACEMENT We are aware of a process change in the manufacture of 853 drive motors Tllis change has resulted in low hour motor failures The process has been corrected All current production machines and motors in stock in Melroe Parts Sales are manufactured with the correct process We have developed a drive motor return procedure which affects the following machines only: All non retailed machines prefix 5128 with the following serial numbers 11531-13035, 13037-13039, 13041, 13042, 13044-13047, 13049, 13052, 13057-13059, 13063, 13064, 13066, 13068, 13069, 13071, 13076, 13077, 13105, 13113-13116, 13118, 13121-13123, 13125, 13126, 13133, 13135 & 13140 All non retailed machines with motor date codes 11 94 through 27 94 ;r If you have one of these non retailed machines, order two service replacement motors (P/N · 6662313), 0-rings (P/N 25K-30508) & Bushings (P/N 6513681) from Melroe Parts Sales Motor kit (P/N 6722529) which consists of one each of the previous parts is not presently available, therefore order the parts separately You will then be contacted by Melroe Service for machine verification A warranty claim, motor return tags and return shipping labels will be sent to you Continued on the reverse side Printed in USA Inspect all removed drive motors to determine if further machine service is required Disassemble the drive motors to remove the star and rollers Inspect the star, rollers and end plate for damage The first sign of damage will likely be a frosted appearance on the '--/ surface of the rollers and/or star Further damage will result in galling or other wear of the rollers, star or end plate If the galling (removal of material) is significant, we then recommend removal, cleaning and inspection of the hydrostatic pump(s) Star Roller ,1 P-3829 IMPORTANT: Affix the warranty parts tag (supplied) onto each returned motor Ship all motors removed from these non retailed machines directly to the manufacturer Use the return shipping label provided  for the cost of the motors and three and one-half (35) hours labor to remove, replace and inspect both drive motors Normal warranty policy will apply for hydrostatic pump service only if required as described above Shipping costs to the manufacturer will be reimbursed NOTE: This Service Letter applies for non retailed 853 loaders only 853 loaders that have been retailed or are in your dealer rental fleet will be handled under normal warranty policy Our experience with this indicates less than 10% will fail and most of these will be within the first 40 hours DIRECT TO: BOBCAT® cY' cY' cY' 0 0 D DATE: 9 August 1994 D MODEL: 7753 (S/N 11130 -12101) SUBJECT: DRIVE MOTOR CASE DRAIN BYPASS A case drain bypass was installed on the drive motors in model 7753 loaders starting with serial number 12102 This bypass significantly reduces the case drain pressure at the motor carrier shaft seal If repeat motor carrier shaft seal replacement is encountered or a drive motor is replaced, we recommend adding this case drain bypass to the motor(s) This affects machines serial numbered 11130 through 12101 only Machines serial numbered 11129 & Below do not have a bypass port in the motors which is required for this update D-2143 Continued on the reverse side Printed in USA To install the case drain bypass onto a loader with a serial number listed above, the following parts are required Order from Melroe Parts Sales Part No Description Qty Ref 6558510 6661022 21K-5 6578804 15K-5 6700025 17K-5 6704787 6578209 Elbow fitting Filter Tee fitting Hose Adapter Hose Elbow fitting Hose Connector 1 2 2 2 1 1 2 1 1 A B c D E F G H I Remove the bypass plug in both motor end housings (see photo) Install the elbow fitting item (G) and hose item (D) Remove existing parts as required and install the new parts as shown / existing E  -----1 ,,     @17-----: " jl'   0 / !::::::: 1 \ -: F p-J ,       7 : : -i---------J ,/ /'E ' B C,:      rz:L' : y Ba, D ! c ,'U ! ----ti( ' ,, G-------------- -------1 1 : : ,/Y ! : 7 ---,--> I \J--existing : ·: fl-/ I L   I r--I !J--  ,, -n --­ --vl ·- E-2 164 · Normal warranty policy applies DIRECT TO: BOBCAT® W W cY D D D D DATE: 19August1994 SUBJECT: BOSS TOOL OPERATIONAL CHARACTERISTICS The use of the BOSS diagnostic tool requires special operation with 763 and 773 loaders The current BOSS tool does not recognize loader models 763 and 773 A new BOSS tool cartridge will be available for using the BOSS diagnostic tool with these loaders Until the new cartridge is available the following procedure for using the diagnostic tool must be followed When using the BOSS tool with a model 763 or 773 loader the display will show invalid model number: Invalid Model#: Model#XXX The next display will ask you to enter model number You MUST enter 7753 DO NOT ENTER 763 OR 773 Enter model # After entering 7753 the display will show: Enter yes Model# 7753 Correct? (yes or no) The display will then show: Model# 7753YOU MUST ENTER NO The tool will then provide the correct Update computer? levels for monitoring system operating parameters DO NOT (yes or no) ENTER YES TO "Update computer?" IMPORTANT: If you enter yes to "update computer?" with ANY model number, the BOSS unit (computer) will be updated with incorrect operating parameters The BOSS unit will continually provide erroneous warning and shut down information making the machine inoperable You would then have two alternatives for placing the machine back into operation Continued on the reverse side Printed in USA 1 	 Contact your District so that he can initialize the BOSS unit He can return the 763 or 773 back to normal operating condition 2 	 Install a service replacement backup BOSS unit (P/N 6661110) and update computer as "'---/ a 7753 This will allow temporary normal operation of the machine until your District can initialize the original BOSS unit NOTE: Normally when asked "update computer yes/no", yes should be entered only when initializing a temporary BOSS backup unit (P/N 6661110) NOTE: The model 763 and 773 BOSS units are internally dedicated to that model only Never install an BOSS unit into a 763 or 773 model loader from a different model loader and vice versa Other models do not have this dedicated information and therefore will not have the required parameter information NOTE: This letter pertains to model 763 and 773 loaders only The model 753 BOSS unit has not changed Normal operation, diagnostic and service procedures apply DIRECT TO: BOBCAT® W  W W D D D D DATE: 	22AUGUST1994 MODEL: 	753H 843H WITH DUAL RELIEF KIT (P/N 6704615) INSTALLED SUBJECT: 	DUAL RELIEF VALVE (P/N 6661225) Dual relief valve (P/N 6661225) is installed in the hydraulic control valve in model 753H and some model 843H loaders This valve performs at two pressure levels It relieves normal system pressure and when in high flow operation it relieves at a higher system pressure We are aware that some dual relief valves (P/N 6661225) may not function properly in high flow operation This can result in major damage to the gear pump, ie cracked end cap If you are servicing a 753H or 843H (with this relief installed) with suspected over pressure damage to the hydraulic pump, inspect the relief valve to determine if it is of the latest design (see below) If not, replace the relief valve Before returning the loader to service, P-3859 check the system low and high pressure relief settings and adjust if necessary The 753H checking and adjusting procedure starts on page 2-8A in the 753H Service Manual (P/N 6720326) The 843H checking and adjusting procedure is on hydraulic flow chart #6722305 in the 843 Service Manual (P/N 6566091 ) All valves installed in current production model 753H loaders are equipped with corrected valves All valves in Melroe Parts Sales are also corrected These valves can be identified by an R stamped on the valve or a date code 02671 or later The date code and R are located on the side of the valve on one of the flats  Normal warranty policy applies DIRECT TO: cY BOBCAT® cY cY 0 0 0 0 DATE: 11 October 1994 MODEL: LOADERS 753, 763, 773, 853 WITH BOSS AND BICS™ SUBJECT: AIR FILTER SWITCH (P/N 6665371) AF2 WARNINGS We are aware of a condition that may exist with some air filter switches used in BOSS equipped loaders This condition only affects loaders equipped with BOSS and SICS These loaders have a sealed connector at the air filter switch This condition results in intermittent AF2 warnings on the BOSS display This is caused by pressure build up inside the switch If you are servicing a BIGS machine for intermittent AF2 warnings, we suggest the following repair: Drill a 030"-040" diameter hole through the connector wall of the air cleaner switch while disconnected (see photo) Install the switch so the hole points downward This will prevent water from entering the contact area and will provide a vent for the switch If a 030"-040" diameter drill is not available, replace the switch All replacement switches (P/N 6665371) are vented  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® Dr"" Dr"" Dr"" D D D D DATE: 13 October 1994 MODEL: 325 & 331 EXCAVATORS SUBJECT: NEW FUEL CAP (P/N 6665423) For some time fuel caps (P/N 6661114) installed on model 300 series excavators have been modified during production The plastic lip on the cap was trimmed for clearance with the tank neck This ensures that the cap inner seal properly seats against the filler neck A new cap is now used which fits directly to the tank with no modifications If you receive a complaint that fuel is seeping around the cap, it may be caused from a cap that was not modified during production If the seal does not seat against the filler neck, we recommend installing this new cap (P/N 6665423) The original caps are green The new cap is black  Normal warranty policy applies Printed in U S A DIRECT TO: []-"" BOBCAT® []-"" []-""  0 0 0 0 DATE: 2 September 1994 MODEL: 325 AND 331 EXCAVATOR SUBJECT: BOOM PIVOT GREASE FITTING CONTACT WITH HOSE We are aware that boom pivot grease fitting may contact one of the work group hoses on model 325 and 331 excavators This may' cause hose damage To eliminate this potential for hose damage, the grease fitting and mounting location will be changed The grease fitting will change to a straight fitting (P/N 1 OH-25) It will be counter bored into the pivot bushing Old Boom P-2905 This change can be made to earlier production machines if damage to hoses has occurred Follow the instructions provided on the reverse side Printed in USA Curl the bucket in completely Move the arm completely under the boom Lower the boom to the ground Stop the engine and remove the key Remove the existing grease fitting Support the boom with a chain or nylon sling Refer to Service Manual (P/N 6722918) Partially remove the boom mounting pin Only move the pin until the pin passes by the hole for the grease fitting Do not remove the pin Drill a 332" diameter pilot hole (drill size Q) in the existing grease fitting location Drill completely through to the bushing center Drill a 3/4" (19 mm) diameter counter bore hole Drill this hole to a depth of 59" (149 mm) for model 331 excavators Drill this hole to a depth of 39" (98 mm) for model 325 excavators Counter bore depth is measured from the point of the drill Important: Do not drill the counter bore too deep Use a drill stop device Tap the hole using a 1/8-27 NPTF tap Only tap far enough so you can thread the new grease fitting (P/N 10H25) in 1 1/2 -2 turns by hand Do not over tap this hole Clean the mounting pin bore Install a new grease fitting (P/N 1 OH25) Replace the boom mounting pin Add grease to the fitting  only Normal warranty policy applies DIRECT TO: Ck"' BOBCAT® Ck"' Ck"'  0 0 0 0 DATE: 2September1994 MODEL: 325 AND 331 EXCAVATOR SUBJECT: BOOM PIVOT GREASE FITTING CONTACT WITH HOSE We are aware that boom pivot grease fitting may contact one of the work group hoses on model 325 and 331 excavators This may cause hose damage To eliminate this potential for hose damage, the grease fitting and mounting location will be changed The grease fitting will change to a straight fitting (P/N 1 OH-25) It will be counter bored into the pivot bushing Old Boom · P-2905 This change can be made to earlier production machines if damage to hoses has occurred Follow the instructions provided on the reverse side Printed in USA Curl the bucket in completely Move the arm completely under the boom Lower the boom to the ground Stop the engine and remove the key Remove the existing grease fitting Support the boom with a chain or nylon sling Refer to Service Manual (P/N 6722918) Partially remove the boom mounting pin Only move the pin until the pin passes by the hole for the grease fitting Do not remove the pin Drill a 332" diameter pilot hole (drill size Q) in the existing grease fitting location Drill completely through to the bushing center Drill a 3/4" (19 mm) diameter counter bore hole Drill this hole to a depth of 59" (149 mm) for model 331 excavators Drill this hole to a depth of 39" (98 mm) for model 325 excavators Counter bore depth is measured from the point of the drill Important: Do not drill the counter bore too deep Use a drill stop device Tap the hole using a 1/8-27 NPTF tap Only tap far enough so you can thread the new grease fitting (P/N 10H25) in 1 1/2 -2 turns by hand Do not over tap this hole Clean the mounting pin bore Install a new grease fitting (P/N 1 OH25) Replace the boom mounting pin Add grease to the fitting  only Normal warranty policy applies DIRECT TO: BOBCAT® cY cY cY D D D DATE: 14 September 1994 D MODEL: SKID STEER LOADERS EQUIPPED WITH BOBCAT INTERLOCK CONTROL SYSTEM BICS™ ONLY SUBJECT: TEMPORARY INSTRUCTIONS FOR SERVICING WITH NO REMOTE START SWITCH This Service Letter provides the recommended temporary procedure for performing service under the operator cab with the engine running until a remote start switch is available A remote start switch for SICS equipped loaders will be available shortly You will be notified as soon as it is available 1 	Stop the loader on a level surface Lower the lift arms Place the loader on jack stands Follow the prncedur-e in the loader-Service Manual ­ A WARNING Engage the brake, lift and block the loader Check that the wheels are clear See Service Manual for more instructions Failure to obey warnings may cause injury or death 2 	 Remove both cab hold down nuts and plates 3 	 Raise the lift arms and engage the lift arm support device Follow the procedure in the loader Operation & Maintenance Manual 4 	 With the engine running , engage the brake and exit the loader Continued on the reverse side Printed in USA 5 	If required for the service procedure you are going to perform, press the traction lock override button A (the green traction light on the Controller will go on) and/or the mode switch (auxiliary button) B while standing in front of the loader NOTE: The traction lock override button will unlock the traction drive when the operator is NOT in the seat and the seat bar is raised The traction lock override button will function if brake pedal is in the engaged or disengaged position 6 	 Raise the operator cab and perform the service required Lower the operator cab when service is completed or to shut off the engine 7 	 To shut off the engine, press the traction lock override button to lock the traction drive The green traction light on the Controller will go off Sit in the operators seat Turn the key to the off position If you have any questions concerning these temporary instructions please call the Melroe Service Department at 701-678-6465 DIRECT TO: cY BOBCAT® cY cY  D DATE: 23 September 1994 D D D MODEL: 607 & 709 BACKHO E SUBJECT: TRANSPORTING BACKHOE We are aware of instances in which model 607 and 709 backhoes have been damaged while in transport This Service Letter describes this damage and how to avoid it When transporting a 607 and 709 backhoe the operator should use proper care to avoid contact with the backhoe dipper or bucket and the ground If the operator is traveling at higher speeds and runs into rough terrain the following can occur The loader tips forward until the backhoe bucket or dipper contacts the ground This places excess loading onto the backhoe boom There is a high probability that when this happens damage to the boom will occur Operators should be instructed to transport the backhoe at lower speeds and to avoid the backhoe dipper or bucket contacting the ground If traveling at high speeds backhoe bucket or dipper contact with the ground must not occur Also instruct operators to fully extend the bucket cylinder clearance for transport This will provide additional dipper and bucket ground The above is provided for your information This type of damage to covered under our warranty policy a backhoe is not Printed in USA DIRECT TO: BOBCAT® cY cY cY  D D FIELD MODIFICATION D D DATE: 23September1993 MODEL: 231 EXCAVATOR (S/N 12001 & Above) SUBJECT: BROKEN FRONT ENGINE TIMING COVER NOTE: 	This Service Letter is revised on 19October1994 The procedure has been expanded to add a notch to the frame cross member We are aware of some 231 excavators which encounter front engine timing cover contact with the frame cross member If left alone this can cause severe engine damage due to loss of oil When this condition is reported or when a model 231 excavator is being serviced, we recommend inspecting the bottom of the front engine timing cover (see diagram) If the timing cover is broken or there are signs of contact with the frame cross member, perform the following procedures Read this entire Service Letter before ordering parts or performing service Continued on the reverse side Printed in USA 1 FRONT TIMING COVER REPLACEMENT: Inspect the front engine timing cover to determine if replacement is required If replacement is required, order and install the following parts: P/N Description Oty 1 6655479 Front timing cover 6653806 Gasket 1 3974461 Gasket 1 3974895 Gasket 1 15EM-180 Washer 1 3966515 0-ring 2 6655162 0-ring 2 3966530 0-ring 1 6631664 Shaft seal 1 3974577 Shaft a-ring 1 6635392 Gasket 1 3974995 Gasket 1 NOTE: When transferring components to the new timing cover it is important to maintain the proper fuel rack stop adjustment Measure and record the depth of the rack stop pin in the existing timing cover (see diagram) Install the rack stop into the new timing cover Adjust the stop pin depth for the distance recorded NOTE: After the new timing cover is installed, the high idle RPM must be checked and adjusted to 2600 RPM if necessary This adjustment is made by throttle cable length and throttle limit screws Refer to the 231 excavator Service Manual for timing cover replacement information We recommend engine removal Important: before removing the engine, measure and record the distance between the top of the fan and the inside top of the fan shroud This distance is required for procedure four later in this Service Letter I I I \ \  - ,,,, FUEL RACK STOP ADJUSTMENT   / MEASURE DEPTH RACK """j""----STOP PIN Continued 2 CROSS MEMBER NOTCH: A notch will be added to the cross member for additional clearance for the two lower timing cover bolts With the engine removed, mark the frame cross member in the location shown Clean the surrounding area of fuel, oil and dirt A WARNING Eye and body protection is requred when welding or grinding Wear approved goggles, helmet and clothing Failure to wear eye and body protection can result in serious injury W-2009-1285 Using an acetylene torch, cut in the area shown and remove the section Take care to make a clean cut because the area will be · enclosed Cut a piece of heavy 1 1/2" angle iron and weld in place along both long edges Make two square end pieces using 1/4" steel Weld these in place on the ends as shown Clean the area and paint Rear of Excavator 6500" B-14247 5250"5250" L--' 0 0 : 1 1,k--­   (/\-====J I Weld four sides I B-14247 Continued on the reverse side 3 ENGINE MOUNT REPLACEMENT: Order and install four (4) new engine mounts (P/N 6534256) Install the two front engine mounts (closest to the fan) 90 degrees from their original position This increases the spring rate of the mounts and reduces engine movement When the front mounts are installed with this method the coolant recovery bottle mounting bracket must be modified Modify the bracket as follows: Remove the bottle by pulling straight up At the weld, bend the bracket toward the rear of the excavator Partially straighten the original 90 degree bend in the bracket to approximately a 40 degree bend The bottle mounting surface is again perpendicular See the diagram Important: Ensure the hose to the recovery bottle is routed properly It must not be bent too tight causing restriction to coolant flow The recovery bottle must not contact the rotated mount or interfere with the hood when closed ORIGINAL MODIFIED POSITION POSITION Coolant ("'- r- Bottle    1 1 I ,t', I I It/ '' I I t ( ' I I I ', ) J 4 SPACER INSTALLATION: Before removing the engine or replacing engine mounts measure the distance between the top of the fan and the inside top of the fan shroud If the clearance is 9" or greater install four engine mount spacers (P/N 6588967) Perform the following spacer installation procedure: If the excavator is equipped with a wire cage fan guard, do the following before installing spacers: Continued A Install a new solenoid mounting bracket(P/N 6588966) OR B Remove the end of the existing fuel stop solenoid mounting bracket Cut the bracket where shown This will provide clearance with the wire cage when the engine is raised Remove the vertical wire nearest the fuel stop solenoid Cut the wire where shown Loosen each upper engine mount nut and install one spacer between the rubber mount and the engine mount bracket Tighten each engine mount nut to 52 ft­lbs (70 Nm) Melroe Company will give compensation for the cost of parts and eight (8) hours labor for engine removal, timing cover replacement and notching the frame cross member One (1) additional hour is allowed for travel time for retailed machines DIRECT TO: cY BOBCAT cY cY D D D D DATE: 8 January 1993 MODEL: 753 S/N 16141 & Below SUBJECT: LIFT ARM REPLACEMENT A new style lift arm (P/N 6703136) is installed on 753 loaders S/N 17962 & Above The old style lift arm (P/N 6579543) is no longer available If installation of the new lift arm is required on earlier machines S/N 16141 & Below, the new lift arm must be modified for tilt cylinder clearance as described below or the tilt cylinder must be replaced with the latest cylinder This is required on these machines due to interference between the tilt cylinder fitting and the new lift arm Lift arm modification: Before installing the lift arm onto the loader, attach the enclosed template to the right side tilt cylinder pocket (see diagram) Scribe around the shaded area and remove the template Remove the material to the scribed line with a hand grinder Ensure a smooth surface along the length of the line There must not be any burrs or nicks A WARNING AVOID INJURY OR DEATH Wear safety goggles to prevent eye injury when drilling or grinding W-2108-1 186 Paint the surface  No warranty is implied Printed in USA en 0 CY) LC> cc et: LaJ c ::z:    >­ !$:! c:> C) ::::E a::: LaJ < 0::: UJ    c:> C) I­ a::: c::> 3: LaJ a::: C) C) cc CY) LC> BOBCAT DIRECT TO: [X] 00 00 o      o      14 January 1993 D---­231 EXCAVATOR (S/N 12280 & Below) D---­ FUEL STOP SOLENOID TIMER KIT (P/N 6587636) A timer module is now installed in current production 231 Excavators (S/N 12281 & Above) The timer modules' function is to provide pull-in current to the fuel solenoid for only a short duration This provides longer fuel solenoid service life and also allows for more starter cranking power Installation of this timer module into earlier machines is normally not necessary, however, if a machine is experiencing repeat fuel solenoid failures, installation of the timer module may reduce this occurrence A Timer module kit (P/N 6587636) is available for these earlier machines The kit includes Installation Instructions (P/N 6722324) With the use of the timer module, when the key is moved to the off position, pause 3 seconds before returning the key to the ignition or start position This ensures resetting of the timer module  Normal warranty policy applies Printed in USA DIRECT TO: cY BOBCAT cY cY  D D D D DATE: 5 February 1993 MODEL: 853 & 853H (WITH 4-BOL T EXHAUST MANIFOLD) SUBJECT: NEW EXHAUST PIPE GASKET (P/N 6705793) A new exhaust pipe to manifold gasket is now available The new gasket (P/N 6705793) provides improved service life If the original gasket needs to be replaced, install this new gasket Tighten the mounting nuts to 35 ft-lbs (47 Nm) torque  Normal warranty policy applies Printed in USA DIRECT TO: cY BOBCAT cY cY D D D D DATE: 9 February 1993 MODEL: 2500 AND 3500 HYDRAULIC BREAKER SUBJECT: IRREGULAR CYCLING We are aware of a condition of irregular hydraulic breaker cycling This condition can be recognized by a varying cycle rate of the breaker which if continued results in breaker stall With the breaker stalled, if the operator turns auxiliary oil flow off and then on again, the breaker will not cycle The breaker does not start to cycle again until after an extended delay If this condition exists, the most likely cause is defective push pins This can be deformation, wear or burrs The corrective action is push pin replacement There are two push pins (P/N 6630643) in both the 2500 and 3500 hydraulic breaker An 0-ring (P/N 58K-238) is also required Refer to the Hydraulic Breaker Service Manual (P/N 6720280) for the correct replacement procedure The irregular cycling condition must not be confused with a hydraulic breaker stall Occasionally during certain types of operation the hydraulic breaker may stall A stall condition can be recognized by an immediate return to operation if the operator turns auxiliary oil flow off then on again  Normal warranty policy applies Printed in USA DIRECT TO: []""' BOBCAT W W D D D D DATE: 2 March 1993 MODEL: 1250 & 1250X HYDRAULIC BREAKER SUBJECT: RETURN PRESSURE COMPENSATING VALVE (RPC) Two model 1250 hydraulic breakers are available The model 1250 (P/N 6531570) is for model 443, 540 and 640 series loaders The model 1250X (P/N 6531578) is for model 220 and 225 excavators The difference between these two hydraulic breakers is in the configuration of their return pressure compensating valve (RPC) The RPC valve can be configured either activated (excavator use) or deactivated (loader use) This difference in configuration requirements is due to the lower return line back pressure of the excavators In instances where the back pressure is high (loaders) the RPC valve must be deactivated Conversion from an activated to deactivated RPC valve is done by changing the parts in the valve The required parts for both conditions is shown below The following parts are required to activate a deactivated RPC valve Ref P/N A 6650372 B 6650373 c 6650374 D 6650295 Description SPRING SHIM 0-RING PLUG Qty 1 4 1 1 Remove the spacer, 0-ring and plug Install the spool, spring, 3 shims, 0-ring and plug The hydraulic breaker is now setup to operate with excavators Add or subtract one shim to achieve optimum performance Continued on the reverse side Printed in USA The following parts are required to deactivate an activated RPC valve Ref P/N Description Qty A 6650375 SPACER 1 B 6650374 0-RING 1 c 6650376 PLUG 1 Remove the spring, shims, 0-ring and plug Install the spacer, spool, 0-ring and plug The hydraulic breaker is now setup for operating with loaders DIRECT TO: cY BOBCAT cY cY D D D D DATE: 4 March, 1993 SUBJECT: ARRIVAL CONDITION ANTI-FREEZE INSPECTION Inspection of the engine coolant can be as basic as checking the fluid level in the recovery bottle This Service Letter outlines the recommended inspection items for cooling system arrival condition 1 COOLANT LEVEL The coolant level should be checked in two locations The radiator should be full and the recovery tank should be at the prescribed level 2 RADIATOR CAP The radiator cap must be of the correct pressure rating and free of defects A pressurized system increases the boiling point of the coolant mixture This extends the high temperature range of protection 3 COOLANT MIXTURE The recommended mixture is 50% ethylene glycol and 50% water This ratio provides the best balance between the following factors and corrosion protection A concentration of more than 50% ethylene glycol may cause premature engine damage Freezing point: A 50/50 antifreeze/water mix provides protection to -34°F Increasing the amount of ethylene glycol to 68% lowers the freezing point to a low of -92°F Increasing the strength of the mixture past 68% actually raises the freezing point Specific heat: Simply stated this is an indicator of the effectiveness of the coolant mixture to pull heat from the engine A 50/50 mix is 80% as effective as water 100% ethylene glycol is only 57% as effective as water Viscosity: Viscosity affects the coolant circulation in the system A high viscosity has poor circulation and can cause uneven temperature throughout the system The viscosity increases dramatically with an increase in ethylene glycol over 50% 100% ethylene glyc0I is too viscous for proper circulation through the engine Boiling point: Increasing the amount of ethylene glycol raises the boiling point Additives: Pure water should never be used as a coolant in Melroe products Ethylene glycol has anti-corrosion and water pump lubricant additives Continued on the reverse side Printed in USA TESTING When testing for the proper 50/50 mixture, the sample should always be taken from the radiator The recovery bottle mixture is not necessarily accurate Someone may have recently added a mix to the bottle This would give you a false indication of the system mixture There are two common tools available for testing the mixture; an optical and a squeeze bulb type The optical type is typically more accurate and can detect an over  strength mix more easily Optical type: MEL-10643 Follow the instructions provided with the tool Check for a correct reading of -34°F A reading off scale indicates a mixture of more than 50% ethylene glycol Adjust the mixture accordingly Bulb type: MEL-10014 Check for a reading of -34°F With ANY reading below -34°F, water should be added and thoroughly mixed with the existing coolant until a correct reading of -34°F is achieved This is required because most bulb type testers can not measure mixtures with more than 50% concentration DIRECT TO: BOBCAT 	ct"' ct"' ct"' · 0 0 0 0 DATE: 9 March 1993 MODEL: ALL 50 SERIES MODEL LOADERS SUBJECT: NEW ENGINE MOUNTS New engine mounts are now installed on current production 50 series machines These new engine mounts provide increased service life New mounts were installed at the following serial numbers: 753 20257 & Above (also S/N 20254 & 20255) 7753 12891 & Above (also S/N 12889)  j 853BASE 510125803 & Above 853 510250321 & Above o-c¥-­ 853H 510375155 & Above 853 508415122 & Above (Europe only) A-@ ' j 853H 509715163 & Above (Europe only)  I c-Q i Each mount consists of the following new parts: 8-$; Ref Part No Description A 6661785 ENGINE MOUNT B 6661787 SNUBBING WASHER c 6706043 SPACER D 6705106 WASHER E 17C-848 BOLT (753 & 7753) E 17C-852 BOLT (853) If engine mount replacement is required for machines with earlier style engine mounts, all four mounts must be replaced Two engine mount kits are available for these machines Refer to BTI 273 dated 1 March 1993 for the correct kit numbers  Normal warranty policy applies Printed in USA DIRECT TO: c:Y' BOBCAT c:Y' c:Y' 0 0 0 0 DATE: 	10 March 1993 MODEL: 	753 (S/N 12218 & Below) 7753 (S/N 12371 & Below) 853 (S/N 510260161 & Below) 853H (S/N 510375092 & Below) 853 (S/N 508415055 & Below) 853H (S/N 509715096 & Below) SUBJECT: 	CAB GROUND A new cab harness is now installed in all 50 series loaders The new harness provides a separate direct ground connection from the cab to the frame This provides a ground current path for lights, windshield wiper, etc In earlier machines, the ground is shared with the system operating unit A separate ground connection from the cab to the frame can be added to the machines listed above This may be required if one of the following conditions are reported: The fuel, battery, engine oil pressure or coolant temperature display changes level when the lights are turned on A fuel code 7 is indicated on the display when the lights are turned on Order ground strap (P/N 6705978) from Melroe Parts Sales Raise the operator cab Install the large end of the ground strap to the harness clamp on the frame (next to the hydraulic tank) Connect the other end to the solenoid mounting bolt on the rear of the cab (see photo) Ensure proper electrical contact  Normal warranty policy applies Printed in USA DIRECT TO: c::tr" BOBCAT c::tr" c::tr"  0 0 0 0 DATE: 5 April 1993 MODEL: ALL SUBJECT: COOLANT RECOVERY BOTTLE FILL LEVEL All current production liquid cooled engines use a recovery type coolant system This system uses a coolant recovery bottle to hold excess coolant Coolant escapes from the radiator due to expansion and enters the recovery bottle As the system coolant cools down, it contracts and draws coolant from the recovery bottle This system maintains a full radiator at all times It is important that the recovery bottle does not become empty This would allow air to enter the system thus reducing system efficiency The recovery bottle should be checked daily while the system is cold The coolant level should be within the MIN COLD (minimum cold) and MAX COLD (maximum cold) levels Some earlier recovery bottles do not have these level indicators These should be kept at approximately 1/3 full when cold Always use a 50/50 mix of water and anti-freeze Printed in USA DIRECT TO: []!"" BOBCAT C11"" C11"" D D D D 12 April 1993 7438 (S/N 18000 & ABOVE) ANY 643/743/7438 W/ ENGINE SHUTOFF KIT 6705289 6648496 HEATER KIT A wire harness (P/N 6703041) has been added to heater kit (P/N 6648496) This harness includes a diode which eliminates feedback voltage from the heater fan motor Without a diode, this heater kit may cause short term engine run-on in the machines listed above These machines have an electric engine shutoff When 	installing this heater kit in the machines listed above, ensure that the kit has the diode 	installed The diode is located in the wire harness (see diagram) If the diode is not present, do one of the following: - / 	1 Order wire harness (P/N 6703041) and install in place of wire harness (P/N 6648457) in the kit 2 Install a 3 amp diode (P/N 3675725) in the wire harness as shown ;ARNESS 6703041 IDIODEHERE !,,\-,  Normal warranty policy applies Printed in USA DIRECT TO: rn' BOBCAT rn' rn'  	D D D D FIELD MODIFICATION DATE: 	15 April 1993 MODEL: 	853 (S/N 508411001-11963-except 11950, 11959 & 11960) 853H (S/N 509711001-11133) SUBJECT: 	EXHAUST SYSTEM IMPROVEMENT NOTE: This Service Letter Replaces Service Letter dated 15 March 1993 A radiator hose bracket and bolt are added to kit (P/N 6722451) When installing kit (P/N 6722451) do the following Inspect the kit for hose bracket (P/N 30H-60) and bolt (P/N 1CM-812) If they are not included, order them from Melroe Parts Sales ! r-The engine exhaust tube in current production 853 and 853H loaders has a four bolt mounting flange Machines with serial numbers listed above have exhaust tubes with a two bolt mounting flange The four bolt exhaust system has proven to be a superior design An upgrade kit is now available This kit (P/N 6722451) provides the required parts to convert to a four bolt exhaust system The kit also includes four of the current production style engine mounts Because engine movement affects exhaust tube life, the addition of the new engine mounts will further improve the service life of the new exhaust tube NOTE: 853 machines (S/N 508411001 ­508411010) require different engine mounts Refer to BTI 273 for the correct engine mounts We recommend installing this kit in those machines listed above which have had exhaust tube failure and are exposed to extremely heavy duty service Melroe Company will give compensation for the cost of the kit and eight (8) hours labor for installation One (1) additional hour is allowed for travel for retailed machines This offer expires on 15 March 1994 Continued on the reverse side Printed in USA When installing kit (P/N 6722451 ), refer to the 853 Service Manual (P/N 6720755) and BTI 273 for installation information Engine removal is not necessary to complete installation of this kit When installing the exhaust manifold and exhaust tube, we recommend fastening the tube (with gasket) to the manifold first" Fasten this to the engine as an assembly Ensure that the muffler inlet is re-sized properly The new exhaust tube must go into the muffler far enough for secure clamping REVISION: Install the bolt and hose bracket (Ref 0 & P) onto the exhaust manifold Secure the radiator hose KIT (P/N 6722451) Qty Part No Description 4 6705106 WASHER 4 6661786 MOUNT 2 6705105 SPACER (1570" ) TAILGATE SIDE 2 6705128 SPACER (1470" ) PUMP SIDE 4 6661787 WASHER 1 6660989 GASKET 1 6659933 MANIFOLD 2 6658215 STUD 6 6513049 BOLT 1 6705793 GASKET 4 6631734 STUD 1 6660665 EXHAUST TUBE 4 6625291 SPACER 4 2DM-10 NUT 1 1CM-812 BOLT 1 30H-60 HOSE BRACKET Ref A B c c D E F G H J K L M N 0 p  · f,,,,,,'-··· r<::::>-A I ! ®-e I0-c ' -0 < \    / H DIRECT TO: Dr" BOBCAT Dr" Dr"Bobcat ,Specialist D D D D DATE: 19 April 1993 MODEL: 231 EXCAVATOR (S/N 12001 -12380) SUBJECT: DUAL PRESSURE RELIEF VALVE KIT FOR TRACK DRIVE I Dual pressure relief valves are now installed in current production model 231 excavators (S/N 12381 & Above) This addition provides increased pressure capability for higher track drive torque The increased relief pressure is activated automatically whenever the operator drives one or both tracks A kit (P/N 6587690) is available to provide earlier machines (S/N 12001-12380) with this feature With this kit, the main relief valve is set at 2500 PSI (1735 kPa) for digging functions The main relief increases to 3000 PSI (20682 kPa) for travel Installation Instructions (P/N 6722403) are included Order from Melroe Parts Sales 231X DUAL PRESSURE RELIEF VALVE KIT 6587690  No warranty is implied Printed in USA DIRECT TO: BOBCAT® V 1 P-"" D DATE: 7 June 1993 0 MODEL: 4408, 443 & 4438 5428, 543 & 5438 SUBJECT: DIAGNOSING HYDRAULIC SYSTEM AIR ENTRY Melroe Company has been made aware of some hydraulic pumps with cracks on their mounting flange This affects only the models listed If you are servicing one of these model loaders with symptoms of air in the hydraulics, be aware the hydraulic pump mounting flange may be the cause Two symptoms of air in the hydraulics are abnormal noise in the hydraulic pump and erratic lift arm or tilt operation  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® 	c::Y' c::Y' W 0 0 0 0 DATE: 	12 July 1993 MODEL: 	753 S/N 511525425 & BELOW 753 S/N 508690328 & BELOW 753 S/N 511350666 & BELOW 7753 S/N 14154 & BELOW 743B S/N 22310 & BELOW 645 S/N 11425 & BELOW 231X S/N NOT AVAILABLE 1600 S/N NOT AVAILABLE SUBJECT: 	FUEL STOP SOLENOID SILICONE BOOT (P/N 6664286) A new fuel stop solenoid is installed in current production 753, 7753, 7438 and 645 model skid steer loaders, model 1600 articulated loaders and model 231 excavators This solenoid features a protective boot made from a silicone material The silicone material provides more flexibility at cold temperatures This results in improved operation of the solenoid There is no visual difference between the old and new boot If an earlier machine (with a serial number listed above) experiences fuel stop solenoid inoperation, the old style boot may be the cause This would be most common in colder environments The symptom of this is the engine won't start This occurs because the fuel stop solenoid does not fully retract If the loader is equipped with a fuel stop timer module, the fuel stop solenoid will start to pull in but then returns to the off position after a short moment If you are servicing a machine for this condition, a service replacement silicone boot (P/N 6664286) is now available The boot is held in place with a cable tie (P/N 6610510) Order both from Melroe Parts Sales  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® 	cY cY cY D D D D DATE: 13 July 1993 MODEL: 231 12,000 SERIES SUBJECT: SWING FRAME MOUNT -HOSE PINCH POINT We have been made aware of a potential hose pinch point If replacement of a work group hose is required, check the swing frame mount and ensure there is no pinch point as described below Inspect the swing frame mount side plate for an abrupt step If this step is the cause of hose abrasion, it must be removed Follow the steps below to remove the step Remove the paint in the area at the end of the step Build up the surface with a few short passes of weld in front of the step Grind the surface of the side plate for a smooth slope This will allow 	the hoses to ride over the side plate Paint Repeat for the other side if required ;r-- Normal warranty policy applies GRIND SMOOTH Printed in USA DIRECT TO: Dr" BOBCAT® cY Dr"  	D D D D DATE: 	14 July 1993 MODEL: 	853BASE S/N 510126110 & BELOW 853 S/N 508411354 -508415187 & 508411351 853 S/N 510250448 & BELOW 853H S/N 510375213 & BELOW 853H S/N 509715221 & BELOW SUBJECT: REVERSE FLOW HARNESS 	-FRONT AUXILIARY A new auxiliary control harness is now installed in all current production model 853 loaders This new harness allows an operator to select reverse flow of the front auxiliary while continuous flow (detent) is selected If this is attempted on earlier 853 loaders, the front auxiliary flow will stop A harness is available for adding this feature onto earlier machines with serial numbers listed above Order harness (P/N 6705284) from Melroe Parts Sales and install as shown below Install the harness between the three-pin connectors of the right hand steering lever A ten-pin connector plugs into the auxiliary control module Connect the harness wire into the pin D location of this connector TO AUXILIARY WIRE HARNESS RIGHT HAND LEVER w A  HARNESS u x M · 0 D u L IDPIND E  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® 	V V V ----, ! DATE: 3 August 1993 MODEL: 231 EXCAVATOR S/N 12000 & ABOVE SUBJECT: HYDRAULIC RESERVOIR NOISE The hydraulic reservoir is equipped with a sealed cap We have received reports that some 12000 series 231 excavators make an annoying popping noise This occurs most often during operations with maximum return oil to the reservoir such as when the boom is lowered rapidly while the dipper is extended A vented hydraulic reservoir cap is now available which eliminates this noise This cap has a filtered vent which prevents reservoir pressurization The cap is available from Melroe Parts Sales Order (P/N 6664220)  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT® 	cYService Manag;r cY cY 0 0 0 0 DATE: 5 August 1993 SUBJECT: REAR AUXILIARY -DIVERTER VALVE IMPROVEMENT An improvement has been made to diverter valve (P/N 6649686) The diverter valve is a component in some rear auxiliary options and field installed kits It diverts hydraulic flow to rear auxiliary quick couplers by the operation of an electric switch located in a steering lever Two improved pilot to open check valves are being installed in this diverter valve These provide less flow restriction This increases flow and allows the rear stabilizers to move up or down faster If slow rear stabilizer operation is reported, the installation of two new pilot to open check valves (P/N 6664212) will provide faster operation To identify a diverter valve which has new pilot to open check valves, check the markings on the end of both valve cartridges The old cartridges are marked 10PC1­ 50 The new cartridges are marked 10PC1-SPF New pilot to open check valves (P/N 6664212) are available from Melroe Parts Sales NOTE: A third pilot to open check valve is installed in the diverter valve This cartridge has no relation to this symptom Replacing it is not necessary DIVERTER VALVE 6649686 r--, The above is provided as !Pchnical information Normal warranty policy applies Printed in USA DIRECT TO: Dr"" BOBCAT Dr"" Dr"" 0 0 0 0 DATE: 18 August 1993 MODEL: 231 EXCAVATOR S/N 12000 & ABOVE SUBJECT: LOW ENGINE PERFORMANCE Melroe Company is aware that some 231 excavators may experience a reduction in engine performance when the fuel level in the tank is low This most likely can occur when the fuel level is 1/2 full or less If a 231 (12000 series) excavator is experiencing one of the following symptoms when the fuel level is low, we recommend installing an electric fuel pump 1 Hard starting 2 Failure to start 3 Loss of RPM (Reduced power) Order the following parts from Melroe Parts Sales: P/N DESCRIPTION QTY equipped with an in-line fuel filter, remove this filter and install the pump in this location This filter is not required and was removed on later units Continued on the reverse side Printed in USA Attach the fuel line from the canister filter to the bottom fitting on the electric pump Attach the fuel line from the fuel injection pump to the top fitting of the electric pump NOTE: If an in-line fuel filter is not present, the fuel line must be cut Connect the (+) wire of the fuel pump to the fuel pump connector in the engine harness This connector is hidden in the conduit near the canister fuel filter The above is provided as technical informaion Normal warranty policy applies DIRECT TO: BOBCAT Dr"  Dr" Dr" D D FIELD MODIFICATION D D DATE: 23 September 1993 MODEL: 231 EXCAVATOR (S/N 12001& Above) SUBJECT: BROKEN FRONT ENGINE TIMING COVER We are aware of some 231 excavators which encounter front engine timing cover contact with the frame cross member If left alone this can cause severe engine damage due to loss of oil This condition may be noticed by oil leakage from the bottom of the front engine timing cover It can also sometimes be identified by noise when the timing cover comes in contact with the frame When this condition is reported or when a model 231 excavator is being serviced, we recommend inspecting the bottom of the front engine timing cover (See diagram) If the timing cover is broken or there are signs of contact with the frame cross member, perform the following three procedures Read this entire Service Letter before ordering parts or performing service Continued on the reverse side Printed in USA 1 FRONT TIMING COVER REPLACEMENT: Inspect the front engine timing cover to determine if replacement is required If replacement is required, order and install the following parts: P/N Description 	Oty1 6655479 Front timing cover 6653806 Gasket 1 3974461 Gasket 1 3974895 Gasket 1 15EM-180 Washer 1 3966515 0-ring 2 6655162 0-ring 2 3966530 0-ring 1 6631664 Shaft seal 1 3974577 Shafto-ring 1 6635392 Gasket 1 3974995 Gasket 1 NOTE: When transferring components to the new timing cover it is important to maintain the proper fuel rack stop adjustment Measure and record the depth of the rack stop pin in the existing timing cover (see diagram) Install the rack stop into the new timing cover Adjust the stop pin depth for the distance recorded NOTE: After the new timing cover is installed, the high idle RPM must be checked and adjusted to 2600 RPM if necessary This adjustment is made by throttle · cable length and throttle limit screws Refer to the 231 excavator Service Manual for timing cover replacement information We recommend engine removal Important: before removing the engine, measure and record the distance between the top of the fan and the inside top of the fan shroud This distance is required for procedure three later in this Service Letter     ,,, FUEL RACK STOP ADJUSTMENT ( - MEASURE DEPTH RACK ----sToP , Continued 2 ENGINE MOUNT REPLACEMENT: Order and install four (4) new engine mounts (P/N 6534256) Install the two front engine mounts (closest to the fan) 90 degrees from their original position This increases the spring rate of the mounts and reduces engine movement When the front mounts are installed with this method the coolant recovery bottle mounting bracket must be modified Modify the bracket as follows: Remove the bottle by pulling straight up At the weld, bend the bracket toward the rear of the excavator Partially  straighten the original 90 degree bend in the bracket to approximately a 40 degree bend The bottle mounting surface is again perpendicular See the diagram Important: Ensure the hose to the recovery bottle is routed properly It must not be bent too tight causing restriction to coolant flow The recovery bottle must not contact the rotated mount or interfere with the hood when closed ORIGINAL MODIFIED POSITION POSITION Coolant r-- 1 I I I J 3 SPACER INSTALLATION: Before removing the ngine or replacing engine mounts measure the distance between the top of the fan and the inside top of the fan shroud If the clearance is 9" or greater install four engine mount spacers (P/N 6588967)  Perform the following spacer installation procedure: If the excavator is equipped with a wire cage fan guard, do the following before installing spacers: Continued on the reverse side A Install a new solenoid mounting bracket (P/N 6588966) OR B Remove the end of the existing fuel stop solenoid mounting bracket Cut the bracket where shown This will provide clearance with the wire cage when the engine is raised Remove the vertical wire nearest the fuel stop solenoid Cut the wire where shown Loosen each upper engine mount nut and install one spacer between the rubber mount and the engine mount bracket Tighten each engine mount nut to 52 ft­lbs (70 Nm) Melroe Company will give compensation for the cost of parts required as described in this letter Two levels of labor compensation will be as follows: 1 Seven (7) hours for those machines which require engine removal and front timing cover replacement 2 Five and one-half (55) hours for those machines which require engine removal only and do not require front timing cover replacement One (1) additional hour is allowed for travel time for retailed machines This offer expires September 23, 1994 DIRECT TO: rn-' BOBCAT rn-' rn-' D D D FIELD MODIFICATION D DATE: 18 October 1993 MODEL: 231 EXCAVATOR (12,000 SERIES ONLY) SUBJECT: TRACK DERAILING Current production 231 excavators are equipped with a track frame with idlers and rollers which can accommodate either rubber or steel tracks If it is equipped with rubber tracks and repeat track derailing occurs, a kit (P/N 6722842) is available to correct this condition This kit contains idlers and rollers which have a larger center rib to better guide the track This kit is available from Melroe Parts Sales Installation Instructions are included in the kit /"'\ Kit (P/N 6722842) includes the following parts: NOTE: This kit must be removed and original parts installed if PLN DESCRIPTION QTY REF installation of steel tracks is 6588999 Front idler 2 A desired 6589006 Track roller 8 B 6589054 Spacer 2 c 6589143 Spacer 2 D 6589129 Decal 2 E 6722843 Instructions 1 Melroe Company will give compensation for the cost of the kit and five (5) hours labor for installation One (1) additional hour is allowed for travel for retailed machines Printed in USA DIRECT TO: BOBCAT® []""' cY  cY D D D DATE: 20 October 1993 D MODEL: 225 EXCAVATOR (12,000 SERIES ONLY) SUBJECT: TRACK DERAILING Melroe Company is aware that some 225 Excavators may experience track derailing in some applications We have investigated this condition and have determined that grease cylinder spring force and travel are the major contributing factors Two spacers are available to optimize the spring function Order two spacers (P/N 6589053) and two spacers (P/N 6589143) from Melroe Parts Sales Install the spacers onto the grease cylinder spring of each track as shown: Refer to the 225 Service Manual (P/N 6720875) when directed A WARNING AVOID INJURY OR DEATH Put jackstands under the blade and rear corners of the under carriage before working under the machine Failure to block up the machine may allow it to move or fall and result in injury or death Place the excavator on four jack stands Two under the corners of the blade (with the blade fully raised) and two under the undercarriage Stop the engine (See photo) Remove the track Refer to page 5-12 Disassemble the track frame to remove the grease spring cylinder Page 5-13 Continued on the reverse side Printed in USA Remove the nut and the end plate collar from the grease spring cylinder Install the small spacer (P/N 6589143) (item 1) onto the threaded shaft (This spacer limits spring travel) Install the large spacer (P/N 6589053) (item 2) between the spring and the end plate collar (This spacer increases spring force) NOTE: Make sure the large spacer is B-14049 centered onto the end plate collar Apply Loctite 242 or equivalent onto the nut Install the nut and tighten until the spring is compressed to 92" (2335 mm) NOTE: It may be necessary to install the grease spring cylinder assembly into a press and compress the spring slightly to start the nut Install the grease spring cylinder into the track frame Reassemble the track frame and install the track Repeat this procedure for the other track After the new springs are installed, each track should be rotated slowly to ensure the track is centered Stop the engine Perform the track tension adjustment procedure as provided in the Service Manual starting on page 5-11  Normal warranty policy applies DIRECT TO: BOBCAT® cY cY cY I D D D D DATE: 14 December 1993 MODEL: 50 SERIES WITH BOSS OPTION SUBJECT: REMOTE START SWITCH MODIFICATION We are aware of a condition that can occur with remote start switch MEL1398 During periods of very cold coolant temperatures, when the remote start switch is in the ignition position, the starter solenoid can energize causing the starter to attempt to turn A simple modification will prevent this condition and will not affect any of the remote start switch functions Perform this modification on all of the remote start switches MEL1398 at your dealership Notify all technicians of this modification Remote start switch modification: 1 	 Cut the blue/black wire near the pin at the large connector 2 	 Remove the switch box cover 3 	 Cut the other end of the blue/black wire near the switch 4 Remove the blue/black wire 5 Install the switch box cover Because this modification takes approximately 5 minutes to perform, no warranty compensation is provided OTC has performed this modification on all units in their stock Printed in USA DIRECT TO: BOBCAT® cY  cY cY D D D D DATE: 15 December 1993 MODEL: 231 EXCAVATOR (12000 SERIES) 331 EXCAVATOR SUBJECT: NEW SWING MOTOR RELIEF VALVE (P/N 6664959) An improved swing motor relief valve is now available The new relief valve is (P/N 6664959) It is a direct replacement for the original relief valve (P/N 947639) and will provide improved service life We recommend using the new relief valve whenever replacement is required The pressure setting on the new relief valve is the same as the old valve If a 231 (12000) series excavator or a 331 excavator has a swing motor relief with internal leakage, the following symptoms will be observed: 1 When the house is moved and the lever released, the house does not stop quickly 2 When operating on a slope the hose has a tendency to drift in the down hill direction If these symptoms are reported it is very likely that one of the swing motor relief valves requires replacement If the symptoms are reported in both directions, both relief valves may require replacement  Normal warranty policy applies Printed in USA DIRECT TO: IX] BOBCAT IX] 00 D      o      D---­ o      DATE: 	13 January 1992 MODEL: 	231 -11000 SERIES 225X (S/N 11999 & Below) 220X (S/N 11001-11999) SUBJECT: 	HIGH TEMPERATURE SEAL KIT FOR DIVERTER VALVE The auxiliary high flow option, for the excavators listed above, uses a diverter valve (P/N 6657013) to control high oil flow to the front auxiliary quick couplers Improved high temperature seal kits are now available as service parts The new kits feature viton seals which withstand high temperatures Order the following kits for applications with repeat seal failures P/N QTY REF ITEM D 6660338 3 SET A \ 6660798 1 SET B 6660800 1 ITEM C ITEM C #)" 6660799 1 ITEM D SETA C-3245 The above is provided for technical information Normal warranty policy applies Printed in USA DIRECT TO: 00 BOBCAT 00 00 D      o      D---­D---­ DATE: 14 January 1992 MODEL: 231 EXCAVATOR (ALL) SUBJECT: ENGINE AIR FILTER ELEMENT The part number for the service replacement engine air filter listed in the parts microfiche is incorrect The correct engine air filter element for 231 Excavators is (P/N 6598492) Please make this correction This will be corrected in the next microfiche revision The incorrect air filter element (P/N 6598749) will not cause any harm, however it will have a reduced service life If you have (P/N 6598749) filter element in stock, it may be used on 2000 series articulated loaders The above is provided for technical information Normal warranty policy applies Printed in USA BOBCAT DATE: 15 January 1992 MODEL: 220 Excavator (S/N 12917 & Below) SUBJECT: SWING PINION GEAR CLEARANCE DIRECT TO: [!] [!] 0---­0---­0---­0---­ The swing drive pinion gear has been lowered 140 inches (36 mm) on 220 Excavators (S/N12298 & Above) This ensures full pinion to ring gear contact This was accomplished by lowering the swing motor mount in the upper structure With this change, the track frame has also been modified to ensure pinion gear clearance If the upper structure frame (P/N 6536581) is replaced on machines (S/N 12917 & Below), the pinion gear clearance with the track frame must be checked If there is not sufficient clearance, material must be removed from the track frame This will prevent damaging the swing motor drive pinion gear while rotating  Normal warranty policy applies FOLLOW THESE STEPS 1 	With the ring gear installed securely, place a straight edge in the notch of a ring gear tooth as shown in figure 1 2 	 With the straight edge against the notch, the tip of the straight edge must extend at least 4 mm ( 160 inch) beyond the bottom of the ring gear before it touches the track frame Check at several points See figure 2 3 	 If the straight edge does not extend the proper distance, re­move the ring gear and grind material from the track frame to achieve the desired clear­ance 0 RING GEAR 0 STRAIGHT EDGE AGAINST NOTCH Fi ure 1 PROPER CLEARANCE 4MM OR MORE t Fi ure 2 INCORRECT Printed in USA DIRECT TO: !Y BOBCAT IY IY 0 0 FIELD MODIFICATION 0 0 DATE: 16 January 1992 MODEL: 753 (With 709 Backhoe) SUBJECT: STOP DEVICE KIT# 6722098 Note: This service letter replaces service letter dated 16 December 1991 Current production 709 Backhoe mounting kit (P/N 6538707) includes two bolt on stop devices These stops bolt to the underside of both lift arms They ensure that the backhoe mount doesn't contact the tubelines which are on the underside of the lift arms These stops are now available for installation onto existing 753 loaders which are equipped with 709 backhoes Melroe Company recommends installing these stops in all existing 753's which are equipped with 709 backhoe mounting kit (P/N 6538707) To make ordering these parts easier, they have been put into kit form Order kit (P/N 6722098) The instructions in the kit explain the correct installation procedure Melroe Company will give compensation for the cost of the kit and one ( 1 ) hour labor for installation One (1) additional hour is allowed for travel for retailed machines Parts List -Kit# 6722098 6586470 STOP 2 73G-620 SCREW 2 6722099 INSTRUCTIONS 1 t SCREW MC -1605 Printed in USA ' -, I DIRECT TO: BOBCAT 	lXJ [Kl 00 o      o      o      o      DATE: 	17 March 1992 MODEL: 	225 EXCAVATOR (S/N 12001 -12302) W/CANOPY 231 EXCAVATOR (S/N 12001 -12033) W/CAB SHELL SUBJECT: 	DISPLAY BACKLIGHT A new wire harness (P/N 6586429) is now installed on current production machines which are equipped with canopies This change provides for continuous display panel illumination while the key is in the run position This wire harness may be added to earlier machines (with canopies) which have serial numbers listed above To install the wire harness you will need to gain access to the ignition switch and the underside of the display panel Connect one end of the harness to the ignition switch "I" terminal and the other end to the cab connector which is not being used The cab connector, has 2 pins with one gray and one black wire  Normal warranty policy applies CAB CONNECTOR GRAY & BLACK WIRES I TO KEY SWITCH "I" TERMINAL 	TO CAB CONNECTOR t------;Efl-"--1  WIRE HARNESS (6586429) ­ 0-2093 Printed in USA DIRECT TO: BOBCAT 	lXI lKJ lXJ D      o      o      o      DATE: 17 April 1992 MODEL: 50 SERIES LOADERS 	753 S/N 16852 & Above 7753 S/N 11381 & Above 853 S/N 12286 & Above 853H S/N 11255 & Above SUBJECT: DRIVE BELT IDLER ASSEMBLY NOTE: 	THIS SERVICE LETTER REPLACES SERVICE LETTER DATED 31 MARCH 1992 THE CHANGES ARE MARKED WITH A SOLID BAR A new drive belt idler assembly is now installed on current production 50 series loaders The new idler assembly offers many improvements over the previous design which provide for increased service life The new design also requires some specific service procedures The purpose of this service letter is to inform dealers of the servicing requirements of this new idler assembly DRIVE IDLER ASSEMBLY 6704419 BRACKET- The new idler assembly features double tapered roller bearings and a dust cap There are two idler assemblies, (P/N 6704419) for 753 and 7753 machines and (P/N 6704476) for 853 machines Both are identical except forthe mounting bracket These new idler assemblies are a direct replacement for the old idlers A loader Service Manual Revision provides a complete disassembly and re-assembly procedure Revision 750-006, 7753-003 and 850-005 are near completion and will be mailed soon See the reverse side for more service 	information Printed in USA The following lists some important service requirements which service technicians must be familiar with 1 	 Recommended oil replacement at 1000 hour intervals 2 	 Only use 15W/50 synthetic oil (Mobil One is an example) Use of any other oil product is not recommended Oil capacity is critical Fill to exact level shown (see diagram below) The correct 13 amount is 3/4 oz (20cc) See the Service Manual for assembly instructions 4 	 Service the seal and wear sleeve as a pair 5 	 The bearings, cups and spacers are a matched set and must be replaced as a unit 6 	 After re-assembly, end play must be checked The correct end play is 005-013 inch (013-033 mm)  Normal warranty policy applies THE OIL LEVEL SHOWN IS WITH NO TRAPPED AIR OIL LEVEL -2­ DIRECT TO: BOBCAT 00  IK] 00 D      D      o      o      DATE: 20 April 1992 MODEL: 7753 SUBJECT: SOLID TIRES AND TRACKS Solid tires are NOT factory authorized for use on model 7753 loaders Solid tires are NOT listed in the sales handbook as a tire option or field accessory Melroe Company will NOT provide warranty compensation due to damage caused by the use of unauthorized options, such as solid tires on 7753 loaders Other items which are NOT factory authorized for use on 7753 loaders are Industrial Grapple, Foam Filled Tires, IATCO Segmented Tires, Solid Tires and Fluid Filled Tires The above is provided for warranty policy clarification Printed in USA DIRECT TO: BOBCAT 	IX] IK] IX] · o      o      o      o      DATE: 15 May 1992 MODEL: 753 SUBJECT: FENDER BRACES KIT (P/N 6704593) A 753 fender repair kit (P/N 6704593) is available from Chicago Parts This repair kit provides repair and reinforcement if a crack has formed on the top of the fender, from severe duty The kit includes braces for both sides and installation instructions -/ 1 NOTE: IF A CRACK EXTENDS DOWN THE INSIDE OF THE CHASSIS, THE ENGINE MAY NEED TO BE REMOVED FOR ACCESS TO FACILITATE CORRECT REPAIR The above is provided for technical information Normal warranty policy applies ' l Printed in USA ·· :·F1e1a··:oo·1F1cA-r10N· · o -' - : : · -· :·--- - -: "·-- -· ­  :· -· 	 '  ' ' DATE: 1s·My· 12· ·:·;·: 0: , · MODEL!  :,,$1N$iQw::'· : , ': : :?7753siN;:t:or2o'f&;BEtOWJEXCEPT$/N 111·91 & 11198) ·: :·  ' ' - :' ·-: ::::;: ;:>?·:<:' :: ·' : 	 ·: · · SUBJECT: JUEL'fIL-fEfi;MQQNT·ceiN' pJ04322) 	·'· '  - -  - ' ·: · : :-: ', - - :' : ··' :,', -: -:· :, : : --: i 	 · ·: · :: ·current prodqtio 753 ar)d ·7753 ioad'rS ae equipped with a'new fuel filter mot· lhe ' ·nawJuei filtr :mountprovid a$61J<::fJ¢·cation for thefilter how;ing The riew :mourit prevents·xce8syibratfon o:f;ttiecfueffjfrr which can reduce·filter performanc: · : · · ·· · ·"·:·: ··· · :: :: ·: · :  : :< <-· ·: ;· ::::b:: ··: : · :·::· :·: " " : '·::·"" · · : A new fuel'flltar :molint·fu:el"filtt andi1Jttaching boltsare being ·Sent to dealers·for · ·instaUaticiri on·tha··affe'etaafiiadiine-serial· numbers:· iiSted above· · · · ' · ' r '   ·,\' !",;' ',·'; ·:::::· :': ' "<'  , h 	: Mefroe Co,mpanYvvil'IQ'iVeco rrlperiatjJorone (1) hourlaborfor installation cifthe:n-w· fuel fllter:mountone:(1J additional hour is allowed ·fortravel for ·etailed units :· :  - : ' --:: : : " · --  , lnstallatio'n:' · : · : ,) 	···  - -:: ::: · : ·  = --,--,,-- ,, ,, -,----------·   :: " "r::' "'"':" ··,,-­Remove··the ·filter ·housfr19 and ·dis"'" : SOLID FuEL'flLTER MOUNT card bot11: mounting bp,lts " · · : "  - 	 · DIRECT TO: BOBCAT 	00 IX] 00 D      o      o      o      DATE: 20 May 1992 MODEL: 7753 SUBJECT: NON-APPROVED ATTACHMENTS AND OPTIONS This letter replaces the Service Letter dated 20 April 1992 The subject of the previous service letter was shown as solid tires and tracks Tracks are an approved option and were incorrectly listed in the subject title Approved attachments and options for the 7753 are shown in the Sales Handbook Items not shown in the Sales Handbook such as solid tires, and industrial grapples are not approved Should a defect in materials and/or workmanship occur, the use of unapproved attachments or tires will be evaluated to determine warrantability The above is provided for warranty policy clarification Printed in USA DIRECT TO: BOBCAT 00  IK] 00 D      o      FIELD MODIFICATION D---­o      DATE: 	22 May 1992 MODEL: 	853 (S/N 12186 & Below) 853H (S/N 11229 & Below) SUBJECT: 	FUEL RETURN LINE Improvements have been made to the 853 and 853H fuel return line These improvements eliminate fuel line bleed down by extending the fuel return hose to the bottom of the fuel tank Fuel line bleed down causes hard starting If an 853 or 853H, with a serial number listed above, exhibits intermittent hard starting, we recommend upgrading the fuel return To upgrade amachine listed above, order the following parts and install as shown P/N DESCRIPTION QTY 6579554 HOSE 1 6661213 CLAMP 1 6553411 GROMMET 1 6598908 FITTING 1 1 Remove 	the injector return line from the 90 degree fitting on the fuel tank 2 Remove 	the return line, grom­met and fitting 3 Lightly lubricate the new grom­met inside and outside Install the grommet into the fuel tank 4 Assemble the fitting, hose and clamp as shown Push this as­sembly into the tank through the grommet 5 Re-attach 	the injector return fuel line to the fuel tank return fitting                             for the cost of parts and one ( 1) hour for installation This offer expires on May 22, 1993 Printed in USA DIRECT TO: 00 BOBCAT 00 00 o      o      D---­D---­ DATE: 25 May 1992 MODEL: 753 SUBJECT: ENGINE PERFORMANCE CHECK Preliminary checks of timing, compression, injector function etc should normally be performed before any major engine work is contemplated Sometimes low engine perfor­mance is caused by external components, injectors, fuel pump, timing, etc It is important that the Technician can identify proper engine performance To identify low engine performance, engage the front auxiliary function (couplers discon­nected) while monitoring high idle engine RPM If the RPM's drop by more than 600, low engine performance is indicated Use the diagnostic tool (BOSS tool) to monitor the engine RPM's Before this check is valid, the machines hydraulic relief pressure setting must be to specification If low engine performance is indicated by this test, the Technician should then continue troubleshooting by eliminating sources of low engine performance These include but are not limited to fuel quality, timing, and injector performance Printed in USA DIRECT TO: ar" BOBCAT ar" ar" D D D FIELD MODIFICATION D DATE: 2 June 1992 MODEL: PLANER ATTACHMENT Hand Crank (S/N 052300719 & Below) Hydraulic (S/N 303600115 & Below) SUBJECT: HEAVY DUTY MOTOR COVER AND SEAL KIT A new heavy duty motor cover is available for planers which have S/N's listed above If you are servicing a planer with a bent or bulged cover the new cover and seal kit should be  installed Excess pressure develops if the Planer is operated with the motor case drain removed or restricted This causes the cover to warp Excess pressure also develops if the operator starts or stops the drum rotation while at full RPM The operator should be instructed to avoid starting and stopping the drum at high RPM The operator should also be instructed to avoid extending the side shift cylinder fully, while operating the planer When the heavy duty cover is installed, the seals may receive excess pressure if the planer is still operated incorrectly To protect from this, seal kit 6722161 must also be installed The following is a list of parts needed to install the new cover The parts can be ordered from Melroe Company Chicago Parts If the heavy duty cover (3/8") is already installed, only the seal kit will be needed P/N Description Oty 6660136 Cover 1 7CM-1220 Bolt 8 6722161 Seal Kit 1 6650201 0-ring 1 · Printed in USA Refer to the Planer Service Manual for the following Remove the motor Remove old cover and discard cover, bolts and 0-ring Install new 0-ring, cover and bolts Install Seal Kit 6722161 Follow Installation Instructions supplied with the kit NOTE: Pack the bearings with grease during assembly NOTE: After assembly the motor must be full of oil before it is rotated See filling the motor case with oil in the service manual Mel roe Company will give compensation for four (4) hours labor for installation One ( 1) additional hour is allowed for travel time for retailed machines The warranty policy is for a period of one year ending 2 June 1993 DIRECT TO: BOBCAT 	00 lXJ 00 D      D      o      o      DATE: 10 June 1992 MODEL: 7753 (S/N 11326 & Above) SUBJECT: 35 INCH TILT CYLINDER (P/N 6539931) A new tilt cylinder is installed on current production 7753 loaders The new cylinder has a 35 inch bore This larger bore provides increased tilt rollback (break-out) force This 35 inch tilt cylinder MUST NOT be installed on a model 753 loader The model 753 loader is not designed to withstand the added structural loading this cylinder would produce Damage caused by the use of a 35 inch tilt cylinder on a 753 loader will NOT be covered under our warranty policy The above is provided for warranty policy clarification The new 35" tilt cylinder can be 	identified by its base as shown below right 325" CYLINDER (P/N 6539145) Printed in USA DIRECT TO: BOBCAT OO  !X)>arts Manager [K] o      o      o      o       DATE: 18 June 1992 MODEL: 843 HIGH HORSEPOWER HYDRAULICS SUBJECT: NEW DUAL PRESSURE RELIEF VALVE KIT #6704615 A new dual pressure relief valve is now available for 843H machines The new relief valve is activated hydraulically when high flow operation is selected This new valve is available as kit #6704615 and may be installed in all existing 843H machines Installation and adjustment instructions are included -­ When the 843H is in normal auxiliary operation, the diverter (selector) valve directs oil from the high flow pump to return This provides low pressure pilot oil in the dual relief valve, for normal operation The pressure should be set to relieve at 2250-2400 PSI When high flow operation is selected, the diverter valve directs oil through the high flow couplers to the attachment The attachment provides resistance to oil flow, which causes the pressure to rise This increase in pressure, in the pilot hose ofthe relief valve, causes the valve to relieve at a new high pressure level This high pressure level should be set at 3000 PSI  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT 00 IKJ 00 o       o      o      o       DATE: 19 June 1992 MODEL: 753 S/N 12156 & BELOW SUBJECT: HYDROSTATIC PUMP BUSHING REPLACEMENT WITH BEARINGS Current production 753 loaders feature hydrostatic pumps with tapered roller bearings on the pintle shafts Previous units were equipped with polymer lined bushings The tapered roller bearings reduce the steering lever force required to operate the loader If the bushings on machines with serial numbers listed above, require replacement, we recommend upgrading to tapered roller bearings on the pintle shaft For convenience, a kit# 6722046 contains the parts required for conversion to bearings Instruction number 6722075 will be available shortly Until the instructions are completed, the hydrostatic pump component repair manual number 6570269 also provides complete pump repair and bearing installation instructions Ensure that your manual has revision 006 16 March 1992 The above is provided for technical information Normal warranty policy applies Printed in USA DIRECT TO: CB""' BOBCAT CB""' CB""' D D FIELD MODIFICATION D D DATE: 22 June 1992 MODEL: 853 (S/N 11863 & Below) Also (11899-11901, 11910, 11914 & 11918­11924) 853H (S/N 11119 & Below) Also (11121-11130 & 11151-11153) SUBJECT: CHARGE PRESSURE SENSOR RELOCATION The charge pressure sensor is relocated from the hydrostatic pump to the left side chassis This provides torextended service life If a machine with a serial number listed above has had repeat charge pressure sensor failure, we recommend relocating the sensor to the chassis as shown below Order the following parts from Melroe parts sales: P/N Description Qty 6563922 ADAPTER 1 83F-3 ELBOW 1 6530901 HOSE 1 85F-3 ELBOW 1 30H-31 CLAMP 1 6704319 MOUNT 1 42H-24 CLAMP 1 17C-416 BOLT 2 850-4 NUT 2 A 1 /4" electrical eyelet connector will also be required Remove the existing adapter and charge pressure sensor from the hydrostatic pump Install the adapter (P/N 6563922) and elbow (P/N 83F-3) in their place Build the sub-assembly as shown above, with the sensors hydraulic fitting pointing up Printed in USA NOTE: 	THE TWO EXTRUDED PROTRU­SIONS ON THE SENSOR CASE, MUST BE LOCATED SO THEIR CENTERLINE WILL BE AT A 45 DEGREE ANGLE FROM THE LOADER CHASSIS (SEE DIAGRAM) Strip back the conduit from both the Yellow/ Lt Blue and Black charge pressure sensor wires until they will reach the left side of the machine The Black wire will be found inside the conduit NOTE: 	DO NOT CUT AND SPLICE THE CHARGE SENSOR WIRES A RESIS­TOR IS CONNECTED INSIDE THE CONDUIT Connect the Yellow/Lt Blue wire to the charge pressure sensor Remove the existing connector from the Black charge pressure sensor wire and install a 1 /4" eyelet connector Install the sub-assembly into the holes pro­vided on the left side of the chassis using the two (2) mounting bolts and nuts Install the Black sensor wire under one of the sub-assembly mounting nuts Connect the hose from the sub-assembly to the elbow on the hydrostatic pump Install the hose clamp under the port block mounting bolt Check for leaks and proper sensor operation Melroe Company will give compensation for the cost of parts and one ( 1 ) hour labor for installation One ( 1) additonal hour is allowed for travel for retailed machines This offer expires on 22 June 1993 -2­ " DIRECT TO: BOBCAT [XJ  [Kl IX] o      o      D---­ D-----­ DATE: 8 July 1992 MODEL: 5428 (S/N APPROXIMATE EARLY 12000'S -13009) SUBJECT: ENGINE FLYWHEEL Melroe Company has determined that some 5428 engine flywheels have been machined incorrectly This engine has electronic ignition and the timing is determined by teeth cast in the flywheel For a period of time these cast teeth were located incorrectly causing the timing to be to advanced Symptoms of this may be one or more of the following: engine run-on (dieseling), hard starting and detonation  (pinging) If a 5428 with a serial number listed above, exhibits some or all of the symptoms above, the machine should be inspected to determine if it has the correct flywheel Follow the procedure below to determine if the correct flywheel is installed If a defective flywheel is indicated, it should be replaced Follow the replacement procedure in the service manual Flywheel inspection (engine timing check): 1 Connect an induction timing light to the no 1 cylinder 2 With the key OFF, remove the plastic plug from pin 5 on the ignition module Connect a ground wire to pin 5 Leave this ground in place continually during the timing check NOTE: ON SOME IGNITION MODULES, PIN 5 MAY NOT HAVE A PLUG YOU MUST DRILL A SMALL HOLE TO GAIN ACCESS IGNITION MODULE The inspection procedure continues on the reverse side Printed in USA 3 Wait ten (10) seconds Turn the key to the ignition position and wait for another ten (10) seconds 4 Start the engine and check the timing while at idle The timing should be approximately 10 degrees BTDC If the timing is far advanced {approximately 15 degrees or more) this indicates a defective flywheel Replace it 5 Seal the hole at pin 5 with the plastic plug or suitable sealer The above is provided for technical information DATE: MODEL: SUBJECT: BOBCAT 16 July 1992 753 (S/N 17945 & BELOW) 7753 (S/N 11474 & BELOW) FUEL SHUT-OFF SOLENOID TIMER MODULE DIRECT TO: 00 [X] 00 o      o      D---­ D----­ A timer module (P/N 6661372) is installed on current production 753 and 7753 loaders The timer modules' function is to provide pull-in current to the fuel solenoid for only a short duration This provides longer fuel solenoid service life and also allows for more starter cranking power Installation of this timer module into earlier machines is normally not necessary, however, if a machine is experiencing repeat fuel solenoid failures, installation of the timer module may reduce this occurrence With the use of the timer module, when the key is moved to the off position, pause 3 seconds before returning the key to the ignition or start position This ensures resetting of the timer module  Normal warranty policy applies To install the timer module into machines with serial numbers listed above, the following parts will be needed P/N DESCRIPTION QTY 6661372 TIMER MODULE 1 35C-516 FLANGED HEAD BOLT 1 83D-5 NUT 1 A 7/16 electrical eyelet connector will also be needed Mount the timer module to the bottom rear door hinge using the bolt and nut Disconnect the electrical harness from the fuel shut-off solenoid and connect it to the timer module harness Installation Instructions are continued on the reverse side Printed in USA NOTE: 753 MACHINES SERIAL NUMBER 11001-11589 HAVE A SHORT WIRE HARNESS (P/N 6703137) CONNECTED BETWEEN THE ENGINE WIRE HARNESS AND THE FUEL STOP SOLENOID THIS HARNESS MUST REMAIN WITH THE ENGINE WIRE HARNESS Connect the timer module to the fuel shut-off solenoid Remove the white/blue wire from the terminal on the starter solenoid Remove the existing eyelet connector and install a 7/16 inch eyelet connector Connect the white/blue wire to the battery terminal of the starter solenoid WIRING DIAGRAM OF 753n753 WITH FUEL STOP SOLENOID FIELD INSTALLED BLACK RED/BLUE TO SHUTDOWN RELAY WHITE/BLUE STARTER SOLENOID BATIERY TERMINAL DIRECT TO: BOBCAT [X]  [Kl [XI D      o      D---­ D---­ DATE: 22 July 1992 MODEL: ALL 853 SERIES LOADERS SUBJECT: NOTCH FOR IMPROVED BATTERY REMOVAL A notch has been added to the bottom of the rear upright on 853 series loaders to provide improved battery access This notch may be added to all previous 853 series loaders The dimensions and location are provided below Continued on reverse side Printed in USA The notch may be formed by grinding or cutting torch NOTE: Remove the battery and cover any combustible areas with flame retardant mate­rial before welding or grinding AVOID lNJURY OR DEATH Have good ventilation when welding or grind­ing painted parts Wear dust mask when grinding painted parts Toxic dust and gas can AWARNING be produced W-2111-0687 Eye and body protection is required when welding or grinding Wear approved goggles, helmet and clothing Failure to wear eye and AWARNING body protection can result in serious injury W-2009-1285  Normal warranty policy applies DIRECT TO: cY BOBCAT cY cY D D FIELD MODIFICATION D D DATE: 10 August 1992 MODEL: 753 (With 607 or 709 Bakhoe) SUBJECT: STOP DEVICE KIT #6722098 NOTE: 	This service letter replaces service letter dated 16 January 1992 The mounting kit is used for both 607 and 709 backhoes Current production Backhoe mounting kit (P/N 6538707) includes two bolt on stop devices These stops bolt to the underside of both lift arms They ensure that the backhoe mount doesn't  contact the tubelines which are on the underside of the lift arms These stops are now available for installation onto existing 753 loaders which are equipped with a 607 or 709 backhoe Melroe Company recommends installing these stops in all existing 753's which are equipped with backhoe mounting kit (P/N 6538707) To make ordering these parts easier, they have been put into kit form Order kit (P/N 6722098) The instructions in the kit explain the correct installation procedure Melroe Company will give compensation for the cost of the kit and one (1) hour labor for installation One (1) additional hour is allowed for travel for retailed machines Parts List -Kit #6722098 Part No Description Oty 6586470 STOP 2 73G-620 SCREW 2 6722099 INSTRUCTIONS 1 I STOP ---+du I n t SCREW MC-1605 Printed in USA DIRECT TO: BOBCAT 00 [Kl IXJ o      o        o       o      DATE: 8 September 1992 MODEL: 753 (S/N 17983 & BELOW) 7753 (S/N 11474 & BELOW) SUBJECT: NEW ENGINE OIL FILL TUBE (P/N 6703738) A new engine oil fill tube is installed on This provides a more convenient location for adding oil This tube {P/N 6703738) may be added to earlier machines which have serial numbers listed above Parts needed for conversion: P/N DESCRIPTION QTY 6703738 OIL FILL TUBE 1 3974461 GASKET 1 6703736 CAP 1 Order parts from Melroe Parts Sales Engine oil fill tube installation procedure: Remove the fuel stop linkage from the engines' stop lever Remove the fuel stop solenoid and throttle linkage bell crank Remove both nuts which fasten the belt shield to the fuel solenoid mount {Item A) Pull the shield away from the engine a small amount You may need to loosen the 2 bottom shield mounting bolts {not shown) Continued on the reverse side Printed in USA Grind the belt shield for filler tube clearance as shown MODIFY SHIELD FOR CLEARANCE AS SHOWN A WARNING Eye and body protection is required when grinding or welding Wear approved goggles, helmet and clothing Failure to wear eye and body protection can result in serious injury Remove the 2 remaining nuts, fuel solenoid mount and old gasket Install the new gasket (P/N 3974461 ), filler tube, belt shield, throttle linkage bell crank and fuel stop solenoid Adjust the shut-off linkage for a 050" (127mm) gap between the lever and stop when the solenoid plunger is seated (run position)(see diagram) Check proper throttle linkage operation and ensure no oil leaks at the new filler tube  No warranty is implied ' ' ' ' ' GASKET 050" (1,27 mm) DIRECT TO: BOBCAT !XI  IKJ 00 D      o      o      o      DATE: 10 September 1992 MODEL: 2500, 3500, 5500 BREAKER ATTACHMENT SUBJECT: CHARGE VALVE ADAPTER New charge valves are now installed on model 2500, 3500 and 5500 breakers These charge valves require a larger diameter charge tool fitting Current charge kit #6568037 (available from Melroe Sales Gwinner) has these larger fittings installed This allows servicing of old and new charge valves An adapter fitting (P/N 6661802) will be required to upgrade existing charge kits for use with the new charge valves Check your kit and order the adapters from Melroe Parts Sales if required Two adapters (one for each end of the tool) will simplify the charging process DIRECT TO: BOBCAT CB""' CB""' CB""' 0 0 0 DATE: 14 September 1992 0 MODEL: 7753 SUBJECT: LIFT CYLINDER FRAME CLEARANCE We are aware of lift cylinders rubbing against the uprights on 7753 loaders The clearance between the frame and cylinder tube is minimal and oftentimes the cylinder base forces itself out and contacts the frame A washer (P/N 27E-18) may be installed between the lift cylinder base and the outside upright This will take up the clearance and keep the cylinder tube away from the frame This washer is not required with the inertia welded cylinders INERTIA WELD (SMOOTH BEAD) NORMAL WELD 0 0 DO NOT INSTALL WASHER A BUSINESS UNIT OF CUIRK EQUIPMENT COMPANY Printed in USA DIRECT TO: BOBCAT CB' rn'  rn' 0 0 0 0 DATE: 17 September 1992 MODEL: 853H (S/N 11373 & Below) SUBJECT: SIDE SHIFT MOTORING SPOOL AND LOCK VALVE The auxiliary spool in the Melroe hydraulic control valve performs the side shift function when a hydraulic planer attachment is used This same spool operates the optional rear auxiliary hydraulics, if equipped This spool has been changed to a motoring spool with lock valve in current production machines S/N 1137 4 & Above This motoring spool prevents side shift drift of the planer attachment The motoring spool may be installed in machines S/N 11373 & Below, if the planer attachment exhibits side shift drift during operation To upgrade an existing machine to include a motoring spool, order the following parts from Melroe Parts Sales If the 853H loader is already equipped with rear auxiliaries, only the motoring spool is needed P/N Description Qty Ref 6586512 MOTORING SPOOL 1 A 6630527 LOCK VALVE 1 B 6702511 AUX TUBELINE 1 c 6702512 AUX TUBELINE 1 D 15K-5 CONNECTOR 2 E 17K-5 ELBOW 2 F 17C-560 SCREW 1 G 25E-15 WASHER 1 H 850-5 NUT 1 I Motoring spool and lock valve installation: 1 	 Raise the lift arms Install the lift arm support device (See the Service Manual for the correct procedure) 2 	 Raise the operator cab (See the Service Manual for the correct procedure) 3 Install the 15K-5 and 17K-5 fittings on the lock valve Continued on the reverse side Printed in USA 4 Remove the bolt, washer and nut from -the tubeline clamp 5 	 Install the lock valve on the top of the tubeline clamp Use the new (longer) bolt, washer and nut Do not tighten the nut until the tubelines are installed 6 	 Connect the tubelines to the lock valve straight fittings 7 	 Connect the other end of the tubelines to the control valve 8 	 Connect the existing side shift hoses to the lock valve elbow fittings 9 	 Remove the auxiliary spool end cap, spring, and spool 10 	 Install the motoring spool, spring, and end cap Replace the 0-ring seal if it is defective 11 	 Add hydraulic fluid if required Check for leaks and ensure correct operation of the planer attachment  Normal warranty policy applies DIRECT TO: BOBCAT IX]  IKJ 00 D      o      D ---­ DATE: 13 August 1992 o        MODEL: 220 EXCAVATOR (S/N 13121 & Below) SUBJECT: NEW HYDRAULIC RESERVOIR INLET SCREEN (P/N 6587234) 220 Excavators have an inlet screen located in the top filler neck of the hydraulic reservoir A new service replacement inlet screen is now available This new screen (P/N 6587234) has an extended solid tube which protects the screen from the tanks edge This edge is removed on all machines above serial number 13121 When servicing these excavators, check the inlet screen for damage If replacement is necessary, install this new screen  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT ar  ar ar D D D D DATE: 20 October 1992 MODEL: 220 EXCAVATOR (12000 Series) (S/N 12998 & Below) SUBJECT: BOOM TO ARM PIVOT PIN A straight pin and retaining bolt connects the boom to the dipper arm on 12000 series 220 excavators This was improved on machines S/N 12999 & Above by replacing the straight pin with a threaded pin and nut The threaded pin and nut prevents the joint from spreading open 12000 series machines can be adapted for use with the threaded pin as described below The parts required are available from Melroe Parts Sales P/N Description Oty 6539760 THREADED PIN 1 1EM-240 WASHER 1 49DM-24 NUT 1 STOP 1 The stop must be produced locally Dimensions are provided on the reverse side 1 	 Fully lower the boom and attachments 2 	 Remove hoses and tubelines as required for welding and grinding access Installation is continued on the reverse side 3 	 Weld the stop in place as shown 4 	 Grind the bushing to remove Grind · the boom surface smooth Be careful not to damage the boom surface A WARNING Eye and body protection is required when grinding or welding Wear approved goggles, helmet and clothing Failure to wear eye and body protection can result in serious injury  750" (20 mm) 375" (9 mm) 'I 1:r-J a 2" (50 mm) 	WELD STOP \ REMOVE BUSHING 104 " (264 mm) 5 	 Insert the threaded pin and discard the straight pin 6 	 Install the washer and nut Tighten to 440 ft-lbs (600 Nm) torque 7 	 Install the hoses and tubelines which were removed earlier 8 	 Check for leaks and proper operation This Service Letter is provided as technical information Normal warranty policy applies DIRECT TO: BOBCAT 00  00 00 D      o      o      o      DATE: 16 November 1992 MODEL: 231EXCAVATOR12000 SERIES SUBJECT: WORK GROUP HOSE INSTALLATION When replacement or service is required on hydraulic hoses, it is important that they are routed properly They must not rub other objects or be stretched This Service Letter provides the procedure for installation of 231 excavator work group hoses The hoses must be covered with nylon hose guard material Place the hoses around the swing post as shown in the diagram below All cylinder base end hoses go on the right side of the post and all rod end hoses go on the left side (as viewed from operator seat) Bring the boom cylinder hoses towards the center and attach them to their respective fittings on the cylinder 8-13828 Continued on the reverse side Printed in USA Place the remaining hoses under the hose clamp in the order shown Leave the hose clamp loose Measure the length of each hose from the center of the hose clamp Adjust each hose for the proper length as shown Bucket hoses 295" (749 mm) Arm hoses 285" (724 mm) Aux hoses 27" (686 mm) Tighten the hose clamp Complete the hose connections After all connections are made, operate the excavator and ensure proper hose positioning through­out the range of boom and boom swing movement DIRECT TO: CB"" BOBCAT CB"" CB"" 0 D FIELD MODIFICATION 0 D DATE: 17 November 1992 MODEL: 231 EXCAVATOR (S/N 12001 -12216) SUBJECT: BOOM CYLINDER PISTON REPLACEMENT A new boom cylinder piston is installed in 231 excavators (S/N 12217 & Above) The new piston reduces the extended length of the cylinder and provides improved cushioning The extended length was shortened to ensure that the boom would not contact any portion of the cab If an excavator (S/N 12216 & Below) has a boom which contacts the cab, the new boom cylinder piston and seal kit should be installed There are two versions of boom cylinders in 231 (12000) excavators Order the correct piston and seal kit for the serial number machine as listed below PISTON SEAL KIT THREAD SIZE MACHINE S/N 6587574 6661051 1"-14 UNF THREADS 12001 -12151 6587573 6586748 1125"-12 UNF THREADS 12152 -12216 Melroe Company will give compensation for the cost of parts and one (1) hour labor for installation One (1) additional hour is allowed for travel for retailed machines This offer expires on 17 November 1993 Printed in USA DIRECT TO: Clr"" BOBCAT Clr"" Clr"" 0 0 FIELD MODIFICATION 0 0 DATE: 4 December 1992 MODEL: 811 BACKHOE (S/N 001 THROUGH 440) SUBJECT: STABILIZER LOCK KIT (P/N 6722159) The current production 811 backhoe features a mechanical stabilizer storage lock This lock provides a mechanical catch to ensure that each front stabilizer remains in the storage position A new stabilizer lock kit (P/N 6722159) is available and may be installed on earlier machines Melroe Company will give compensation for the cost of the kit and four (4) hours labor for installation One (1) additional hour is allowed for travel for retailed machines This offer expires on 4 December 1993 During installation of the kit, the stabilizer cylinders must be removed and the base end bushings trimmed Follow Installation Instructions (P/N 6722160) which are included with the kit WAllHING ,    ·r ------(Q =:::=­ u  ! STABILIZER LOCK KIT  6722159 Printed in USA BOBCAT DIRECT TO: cY' c:Y' W D D D D DATE: 08 December 1992 MODEL: 220 EXCAVATOR (S/N 11309 & Above) 225 EXCAVATOR (S/N 11105 & Above) 231 EXCAVATOR (S/N 11137 & Above) SUBJECT: FUEL TANK DRAIN The fuel tank is equipped with a solid drain plug on the model excavators listed above If the fuel becomes contaminated with water, this plug must be removed and the water drained out If fuel contaminated with water is a reoccurring problem, this plug can be fitted with a drain valve Order drain valve (P/N 72F-1) from Melroe Parts Sales Siphon the fuel from the tank Remove the drain plug Drill and tap the center of the drain plug for a 1/8"-27 pipe thread Install the drain valve and drain plug into the fuel tank Fill with fuel Check for leaks The addition of this drain valve will simplify draining water from the fuel tank Earlier S/N machines were equipped with drain valves }{ FUEL TANK ····················· ··· ··· ···· ············ :::::::::::::::::::::::::::::::::::::::::::: -DRAIN PLUG  / DRILL & TAP FOR A DRAIN VALVE 1/8"-27 72F-1 c::I:::i  No warranty is implied Printed in USA DIRECT TO: cY BOBCAT cY cY D D D D DATE: 3 January 1991 MODEL: 443, 5428, 543, 6428, 742, 3022 & 220 Excavator SUBJECT: Sealed Starter A sealed starter is available as a service replacement for installation on machine models listed above The sealed starter will provide better protection against dust and debris when operating in severe conditions The sealed starter, part number 6658841, can be ordered from Melroe Parts Marketing, Chicago (This starter is o!:!! y available through Melroe Parts Marketing) Starter, 6658841, will directly replace starter, 6599152 and 6658835 on these models and is offered as a field accessory  only No warranty is implied Printed in USA DIRECT TO: c:Y' BOBCAT c:Y' W 0 0 0 0 DATE: 11 January 1991 MODEL: T208 SUBJECT: Servicing the Air Cleaner Proper procedure must be followed when servicing the engine air cleaner Extra care must be used to assure that the filter assembly is clean, properly oiled and correctly assembled before installing it onto the mounting base Periodic cleaning of the foam pre-cleaner is essential to assure proper engine operation The following step-by-step procedure will assure a dust proof installation: 1) Service the air cleaner in an area free from dusty conditions 2) Remove the end cover and filter assembly Wipe the cap and base clean, with a clean cloth 3) Wash the foam element in kerosene or liquid detergent and hot water Wrap the foam element in clean toweling and squeeze dry CAUTION: DO NOT USE GASOLINE, CARBON TETRACHLORIDE OR PAINT THINNER FOR CLEANING 4) Saturate the foam element in light oil, then squeeze out excess oil 5) Install the foam element over filter element and install them into the cap (Figure 1) 6) Press together FIRMLY (Figure 2) 7) Install the assembly on the base and close the two latches 8) Replace air cleaner assembly every 50 hours of operation Engine failure due to improper air cleaner maintenance is not warrantable Figure 1 Figure 2 Printed in USA DIRECT TO: BOBCAT cY  cY cY 0 0 0 0 DATE: 28 January 1991 MODEL: 4408 SUBJECT: Hard Starting/Stalling Engine Hard starting of engine or engine stalling problem may be due to a sticking inlet needle valve A carburetor kit is available for correcting this problem The kit, P/N 6648829, can be ordered from Melroe Parts Marketing The kit contains an inlet needle with pull-off clip and a replacement gasket The clip prevents the needle from sticking in the seat (The kit also contains a needle with coil type spring This needle is for a different mode engine and can be discarded) The above is provided as technical improvement information only Normal warranty policy applies Needle W/Clip Installed Needle W/Clip on Float Adj Tab Installing Float/Needle W/Clip Printed in USA DIRECT TO: BOBCAT Dr""  Dl""" Dl""" D D D D DATE: 29 January 1991 MODEL: 2500, 3500 Breaker SUBJECT: Tilt Stop The tilt stops on the present production breaker mounting frame, P/N 6575712, have been revised to allow clearance when used on the 750 & 853 Series loaders If an older (740 & 843 Series) mounting frame is used on the 750 & 853 Series loader, it is necessary to remove about 1/4 inch of material from the stop, as shown This will prevent interference and limiting of the tilt angle of the breaker frame 190"  only Printed in USA DIRECT TO: cY BOBCAT cY cY  D D D D DATE: 30 January 1991 MODEL: 225 (11000) Series; 231 (11000) Series SUBJECT: Ground Wire for Fuel Sender Erratic tank level indication on the fuel gauge may be caused by improper grounding of the fuel sender This condition can be remedied by adding a 14 gauge black wire, 72 inches (1830 mm) long with 1/4" (6 mm) ring terminals, to the sender circuit ' To install the ground wire: 1 	 Remove the seat and swing motor cover 2 	 Install the wire in a 1/4" conduit and fasten one end to one of the sender mounting screws 3 	 Route the wire along the existing sender wires and fasten the other end to the mounting screw for the large relay  only Normal warranty policy applies Printed in USA DIRECT TO: cY BOBCAT cY cY D D D D DATE: 30 April 1991 MODEL: All Loaders with Melroe Valve SUBJECT: NEW SEAL FOR CONTROL VALVE SPOOL A new improved seal has been designed for the control valve The new seal, P/N 6659554, is of different design and material (color­ orange) and is a direct replacement for the formerly used seals, part numbers 25K-30020, 6632204 or 6646372 Part numbers of Seal Kits have changed as a result of the new seal Old Seal Kit New Seal Kit Model Used On 6531567 6539276 440, 4408, 443, 540, 543, 641, 642, 6428, 643, 741, 742, 7428, 743, 7438, 743DS, 843, 8438, 1600, 2000, 2400, 2410 6532864 6539277 440, 443, 540, 5428, 543, 640A, 641, 642, 6428, 643, 741, 742, 7428, 743, 7438, 743DS, 753, 800A, 843, 8438, 853, 1600, 1600A, 2000, 2400, 2410 6532866 6539278 753, 853 6593675 6539279 630A, 800A, 1213, 1600A 6593676 6539280 1213 6593677 6539281 630A, 800A, 1213, 1600A 6594238 6539282 4408 6594239 6539283 4408 The new seal 6659554 is available from Melroe Parts Marketing and will service all versions of the Melroe valve A special tool, (MEL-1408) is available from Owatonna Service Tools for installing the seal in the control end counterbore of EARLY BUILT valves The tool will compress the seal lip to clear the counterbore chamfer for easier installation Attempting to install the seal in early built valves without using the tool can result in damage to the seal Later production valves will have a larger chamfer entering the counterbore, therefore, seals can be installed without the tool on those valves PROCEDURE FOR INSTALLING VALVE SPOOL SEALS Melroe Valve with Counterbore (Early) 1 	Remove the bonnet Pull spool, retainer bushing and old seal out together Remove the seal from the front counterbore also Discard the old quad ring or 0-ring seals (Figure 1) Figure 1 2 	Install the new seal into the rear counterbore, with the lip facing IN, toward the center of the valve Install the spool, slowly pushing it through the rear seal (Figure 2) 3 	Install the bonnet and install and tighten the screws With the spool in place, slide the new seal over the spool with the lip facing IN, toward the valve (Figure 3) Seal Figure 3 4 	Using the special tool, MEL-1408, slide the tool over the spool and against the seal Push the tool until a slight "snap" is felt, which indicates that the seal lip has entered the counterbore Install the retainer bushing, rubber boot and the screws (Figure 4) Figure 4 Melroe Valve W/lnternal Seal Grooves (No Counterbores) 5 	Remove the spool and old seals from the grooves Install the new seals in the front and rear grooves, with lips facing IN toward center of valve (An 0-ring Pie is helpful in guiding the new seals into the grooves) (Figure 5) 6 	Using a belt sander or fine grinding wheel, remove the sharp edge from the first groove of the spool Round it off This is the only edge on the spool that will need to pass through the front seal The sharp edge will damage the seal if it is not removed by sanding or grinding before installing the spool (Figure 6) Figure 6 7 	Install the spool through the rear of the valve The spool will pass through the rear seal easily When the spool reaches the front seal, slowly press and turn the spool through the front seal Install the rear bonnet and screws (Figure 7) CAUTION: 	Do not attempt to pull the spool out, or the rear seal will be destroyed Figure 7 On Future Production Melroe Valve (Counterbore W/Larger Chamfer) 8 	The new seal can be pushed into the valve by the retainer bushing The larger chamfer on the counterbore helps guide the seal in No tool is required (Figure 8) Figure 8 -4­ DIRECT TO: []!""" BOBCAT Dl""" Dl""" D D D FIELD MODIFICATION D DATE: 17 May 1991 MODEL: 220 Excavator S/N 11501 thru 12529 SUBJECT: ENGINE SHUTDOWN CABLE The engine shutdown cable 6653726 has been replaced by an improved cable, 6659263, on present production machines The new cable (6659263) has also been made the replacement service part If cable P/N 6653726 fails, replace it with cable P/N 6659263 Melroe Company will give compensation for one (1) hour labor to replace the failed cable with the improved cable One (1) additional hour is allowed for travel time for retailed units Printed in USA DIRECT TO: Dr"" BOBCAT cY cY 0 0 0 0 DATE: 	20 May 1991 MODEL: 	641, 643, 741, 743, 743DS, 843, 843, 974, 980, 1600, 2400, 3023 SUBJECT: 	GEAR REDUCTION STARTER NOTE: This replaces dated 3 August 1990 Present production Bobcat loaders models listed above have model 28MT Delco gear reduction starters installed on the engine The formerly used model 22MT and 27MT starters are no longer available, except as remanufactured units The new gear reduction starter directly replaces the old starter A new support bracket is used with the new starter on the Model 643, and Model 843 with Isuzu Engine When installing the gear reduction starter on earlier Model 643 or 843 (W/lsuzu Engine) loader, the following parts will also be needed: MODEL 	P/N DESCRIPTION QUANTITY 643 6701847 Bracket 1 843 6701618 Bracket 1 843 6701628 Spacer 1 843 5CM-1016 Screw 1 843 5CM-1030 Screw 1 Service Parts for the old starters will continue to be available from Melroe Parts Marketing, in Chicago Service Parts for the gear reduction starters are available from Melroe Parts Three different gear reduction starters are currently being used in production of Bobcat Loaders and the Model 3023 Trencher Printed in USA The following part number starters are used for Loader Models, as indicated The attached Illustrations show the breakdown of the starters and which parts are serviced: STARTER P/N 6649676 6651636 6651210 STARTER (Delco 1113273) 4 1 I 3 5 ,? I :----fl -l-----L ! 6-fl· ' I :, 7 I 13 12 : I I r-o-() 24  (B®l I II I I I II 14 	i I 17 18 I 22 23 25 i ep 1& 19 20 21 I  	! r----------------------------------------' : : 26 10 28  ,--;;L ! 8 L- !H--:--1 I 29 I j : r-------------------------a    J ' 33 I ' : 37 34 {';, 30 I 35 36 I 38 ,-34 31 Ii I I I et° I L--{)(D(!!ll9-ct-- 0 @· · = 39 I I I I 40 	41 32 11 MODEL T-440, 643, 743, 7438, 743DS, 753, 825, 1600, 3023 980 631, 641, 731, 741, 843, 8438, 853, 943, 974, 1213, 2000, 2000RTF, 2400, 2410 STARTER (Cont'd) (Delco 1113273) Ref Part No Number Ooocrtptlon RU ,, D-2119 1 2' 3'   NSS- STAKlK SCREW SOLENOID 1 2 1 4' 5'  · 15658572 1E­ BOLT LEVER WASHER 1 1 1 7  7DM--6 13G­6658566 NUT SCREW BRUSH 1 2 2 10· 11 · 12' NS5 NSS PIN BOLT PLUG 1 1 1 13", 15· NS5 6658567 WASHER WASHER BUSHING 1 1 1 17' 18' ,  6658579 NSS H58573 HOUSING DRIVE RING STOP 1 1 1 20· 21· 1 9 6658579 1658571 · DRIVE SUPPORT SUPPORT -'""'"' 1 1 1 22· 23· 24' , NSS NSS DRIVE SHAFT WASHER WASHER 1 1 2 25 26' 27 ' """ 6658577 NSS WASHER SUPPORT BOLT m'llture 1 1 1 28' 29· 30 """ 6658580 NSS GASKET FRAME ASSY SCREW 1 1 2 31· 32· 33· NSS 6658575 13Glll-408 WASHER FRAME SCREW 2 1 2 34· 35 35 M58565 NSS 11658518 BRUSH SPACER BEARING 2 1 1 37· 38' 39· 6658574 6658570-- ARMATURE BEARING SPRING 1 1 40' 41' 6658511 1"1VLUCnASSY 0-RING b<uoh 1 1 -2­ -, STARTER STARTER !Delco 11132761 !Delco 11132761 Ref Part No Number Descrio1ion Remarks Serial Number Q1y 4 s;I 3 I I 1 :-----/----I I I I t ·---------ca> l 6" rS, : I : 7 16 : 13 12 I : I I 0 14@    r - Ll  -?®a@ ' ®=-i ' n 111 I I I 24 : , 19 I 21 22 : ·cp 211 : 15 I I r--------------------------------------- I ! I i i r-AL JJ 10 L--fJlJ==-L:?-:----1 J7 29 d'-1 l r--------------------------------JI I I 33 : £:, L--@@---, 0 31 39 lif I 40 41 1 2 3 6651636 NSS 6658562 STARTER SCREW SOLENOID 1 2 1 4 5 6 1CM·650 6658572 1EM·60 BOLT LE VER WASHER 1 1 1 7 8 9 7DM·6 13GM·404 6658566 NUT SCREW BRUSH 1 2 2 10 "12 N» NSS NSS PIN BOLT PLUG 1 1 1 13 14 15 NSS NSS 665B567 WASHER WASHER BUSHING 1 1 1 16 17 18 66585B5 NSS 6658573 HOUSING RING STOP drive 1 1 1 19 20 21 6658583 6658578 6658571 DRIVE DRIVE CENTER suppQr1 support 1 1 1 22 23 24 6658576 NSS NSS DRIVE WASHER WASHER shaft 1 1 2 25 26 27 NS> 6658577 NSS WAHER ARMATURE BOLT support 1 1 1 28 29 30 NoS 6658580 NSS GASKET FRAME SCREW assy 1 1 2 31 32 33 N» 6658575 13GM·40 8 WASHER FRAME SCREW 2 1 2 34 35 36 6658565 NSS 6658569 BRUSH SPACER BEARING 2 1 1 37 38 39 6658574 6658570 6658568 ARMATURE BEARING SPRING 1 1 4 40 41 6658564 6658581 BRUSH O·RING holder assy 1 1 STARTER (Cont'd) STARTER !Delco 11132811 (Delco 1113281 1 Ref Part No Number Descric1ion emar s um ' ly , IN be 0 :, 5 / I 1 r-----j I·/---- I I ------cC) : 6-fj; l I f 1 1 6 : 13 1 2 r-0-"" 14 I %,) I -- 24 (© II -? @=-: , 1111 I I I I n ' 19 2G 21 22 l I '  : r--------------------------------------- I I I i i 10 ,-;; L  Jr=t :---1  3 1 ! I I r--------------------------------J I I 33 -33 : I : 34-1 31 L--{l@-©--& Q [Jr·- i I I I I I 1-­ 1 31 31 11 17 11 41 32 , 2 3' 6651210 NSS 6658562 STARTER SCREW SOLENOID I 2 1 4' 5 · 6' 1CM·650 6658572 1EM·60 BOLT LEVER WASHER 1 1 1 7' 8 ' 9' 70M·6 13GM·404 6658566 NUT SCREW BRUSH ' 2 2 10 "12 NSS NSS NSS PIN BOLT PLUG ' '1 13 14 15' NSS NSS 6658567 WASHER WASHER BUSHING 1 1 1 16 ' 17 18' 6658586 NSS 6658573 HOUINU DRIVE RING STOP 1 1 1 19 ' 20 ' 21' 66585ts:J 6658578 665857 1 DRIVE DRIVE SUPPORT CENTER SUPPORT '1 1 22 · 23 24 665ts576 NSS NSS DRIVE HAFT WASHER WASHER 1 1 2 25 25· 27 NSS 6658577 NSS WAHER SUPPORT BOLT Armature 1 1 1 28 29· 30 NSS 6658580 NSS GASKET FRAME ASSY SC REW 1 1 2 3 1 32" 33 NSS 6658575 13GM·408 WASHER FRAME SCREW 2 1 2 34" 35 36 ' 6658565 NSS 6658569 BRUSH SPACER BEARING 2 '1 37 ' 38 ' 39 ' 6658574 6658570 6658568 ARMATURE BEARtNG SPRING 1 '4 40 ' 4 1 6658564 6658581 8RUSH HOLDER 0 -RING Assy 1 1 ( -3­ DIRECT TO: BOBCAT IY  IY IY 0 0 0 0 DATE: 3 June 1991 MODEL: 3022/3023 SUBJECT: DIODE ADDED TO PROTECT PARKING BRAKE A Diode has been added to the wiring harnesses of the Trencher Power Units This change causes the travel motor to automatically shift to High Range whenever the parking brake is engaged, and reduces the ability to drive through the brake The harness change became effective on machine serial numbers 11056 (3022) and 11720 (3023) The above is provided as product improvement information only DIRECT TO: BOBCAT Ol""'  Ol""' Ol""' D D FIELD MODIFICATION D D DATE: 13 June 1991 MODEL: 2400 SUBJECT: BUCKET POSITION VALVE The Anti-Rollback feature used on the model 2400 MTC was replaced by the Bucket Position Valve system upon introduction of the model 2410 MTC The Bucket Position Valve (BPV) feature is being offered as a Field Modification kit to replace the Anti-Rollback mechanism used on the 2400 MTC loader Conversion Kit, P/N 6538802, contains the necessary parts and can be ordered from Melroe Parts Marketing for conversion of machines Installation Instructions are included in the kit Melroe Company will give compensation for the cost of the parts plus eight (8) hours labor for installation This offer expires on 31 July 1992 Printed in USA DIRECT TO: []!""" BOBCAT cY cY D D SAFETY NOTICE D D DATE: 	28 June 1991 MODEL: 	843 S/N 23999 & Below SUBJECT: 	SERVICE LETTER-SAFETY NOTICE "Bobcat Loaders Equipped with Cab Heater Kit, P/N 6564520", dated 12 Nov 1990 On 12 November 1990 Melroe Company issued a Safety Notice advising all Bobcat Dealers to inspect Heater Kit, P/N 6564520 for a hose insert (fitting) which did not meet engineering specifications The Model 843 loader, S/N 23999 & Below, was not included among the affected models It has now been determined that serial number machines listed above are also affected Dealers are instructed that these machines are also included in this Field Modification Program A copy of the original is provided for your information and instructions Printed in USA DIRECT TO: cY BOBCAT cY cY D D D D DATE: 15 July 1991 MODEL: 220 Excavator SUBJECT: FRAME TO SWING CIRCLE MOUNTING PROCEDURE When installing the frame onto the swing circle, one of two procedures will need to be followed One procedure uses screws with tapered heads The other uses alignment pins Both procedures ensure correct 	placement of the swing motor within the swing circle Determine which procedure to use by inspecting the frame, see figure 1 If the frame doesn't have the three locating holes then the tapered screw procedure must be used If the frame r- has the three locating holes then use the pin alignment procedure / NOTE: 	All service replacement frames have the three locating holes and the pin alignment procedure must be used Fig 1 Three 2 inch holes shown with alignment pins installed Printed in U,S,A TAPERED SCREW PROCEDURE Using an overhead hoist, lower the frame to the swing circle Continue to support the frame with the hoist Install the three tapered screws P/N 6539680 into the swing circle an equal distance apart Lower the frame to the swing circle as you continue to turn the screws evenly into the swing circle The tapered screws guide the frame into alignment When the tapered screws are tight, install the proper mounting bolts in the remaining holes (use LocTite) Tighten to 45 ft-lbs (61 Nm) torque NOTE: If lock washers were used with the original bolts, replace them with hardened washers P/N 27E-6 Remove the three tapered screws and install the 3 remaining bolts in their place (use LocTite) Tighten to 45 ft-lbs (61 Nm) torque Remove the hoist Install the swing motor Remove caps or plugs from the swing motor Do not install hoses Check the swing motor to swing circle gear engagement Ensure that there is backlash between the gears through 360 degrees rotation Check for backlash by moving the frame back and forth at several points throughout its rotation There must be some backlash present PIN ALIGNMENT PROCEDURE Using an overhead hoist, lower the frame to the swing circle Continue to support the frame with the hoist Apply LocTite to the swing circle bolts Install the bolts through the frame into the swing circle but do not tighten them NOTE: If lock washers were used with the original bolts, replace them with hardened washer P/N 27E-6 Remove paint from the three alignment pin holes Insert the three alignment pins P/N 6539805 into their holes The frame may need to be repositioned until all alignment pins are installed The pins ensure alignment of the swing motor, see figure 2 The tapered end of the alignment pin will locate itself between the teeth of the swing circle -2­ Fig 2 Remove the hoist Tighten the frame to swing circle mounting bolts to 45 ft-lbs (61 Nm) torque Remove the alignment pins Install the swing motor Remove caps or plugs from the swing motor Do not install hoses Check the swing motor to swing circle gear engagement Ensure that there is backlash between the gears through 360 degrees rotation Check for backlash by moving the frame back and forth at several points throughout its rotation There must be some backlash present Tapered Screw P/N 6539680 Alignment Pin P/N 6539805 This procedure is provided as technical improvement information only No warranty is implied The above information will be added to the Service Manual in the near future -3­ BOBCAT DATE: 6 August 1991 MODEL: 843, 8438 SUBJECT: Pump Alignment Specifcation Change DIRECT TO: cY cY cY D D D D The height specification is changed to improve the U-Joint and pump alignment The former specification of 1140" is changed to 1152" (Fig 1) B-6938 When using MEL-1395 (Pump/Engine U-joint Alignment Tool) add a flat washer, 0120" thick, to each front (2) and rear (1) spacer, MEL 1395-3 & MEL 1395-4  only Service manual revision is forthcoming DIRECT TO: []""' BOBCAT cY cY D D D D DATE: 15 August 1991 MODEL: 753, 7753 & 853 SUBJECT: DRIVE BELT IDLER BEARING Drive belt idler bearings currently being installed on 753, 7753 & 853 loaders are labeled "NTN" All service replacement bearings must also be labeled "NTN" Some loaders were equipped with drive belt idler bearings which were labeled "NSK" These bearings may have a reduced service life as a drive belt idler bearing When installing a service replacement drive belt idler bearing P/N 6651452, only install those that are labeled "NTN"  only Normal warranty policy applies Printed in USA DIRECT TO: c:Y BOBCAT cY cY D D D D DATE: MODEL: SUBJECT: 18 September 1991 220 EXCAVATOR SWIVEL JOINT PIN AND STOPPER PLATE The swivel joint in a Model 220 Excavator has a rotor which turns with the frame This is accomplished with a pin which rides in a notched stopper plate (See figure 1) The original pin (S/N 12403 & Below) is a roll pin If the roll pin becomes damaged, replace it with a 10 mm solid pin P/N 6538824 Install the domed end of the pin into the rotor, not the tapered end Use LocTite #609 retaining adhesive compound or equivalent Stopper Plate E-2037 Figure 1 Swivel Joint The rotor P/N 6658955 on current production machines S/N 12503 & Above have the pin welded in The pin is also larger in diameter and the stopper plate has a notch to fit the larger pin If the rotor P/N 6533947 on machines S/N 12502 & Below is replaced, you must also replace the stopper plate with P/N 6538801 This stopper plate has a notch to fit the larger welded in pin The above is provided as service improvement technical information only Normal warranty policy applies Printed in USA DIRECT TO: c:t"" BOBCAT c:t"" c:t"" D D D FIELD MODIFICATION D DATE: 19 September 1991 MODEL: 231 EXCAVATOR SUBJECT: OIL COOLER KIT P/N 6539451 A larger oil cooler is now standard on 231 Excavators The larger oil cooler ensures that the hydraulic oil temperature stays within the normal range when the ambient temperature is very high and especially when a hydraulic breaker is being used It is recommended that the larger oil cooler be installed on earlier machines, S/N 11276 & Below, if they are equipped with a hydraulic breaker Installation instructions are included with the kit The cooler kit 6539451 may be ordered from Melroe Parts D-2147 Mel roe Company will give compensation for the kit and five ( 5) hours labor for installation One (1) additional hour is allowed for travel time for retailed machines Printed in USA BOBCAT DATE: 24 September 1991 MODEL: T116 SUBJECT: FUEL PUMP PULSE TUBE DIRECT TO: 00 Service Letter IX] [X] D      o      o      o      We have received reports of T116 fuel pump pulse line filling with engine oil A small amount of oil in this line will make the fuel pump inoperable The most probable cause is porosity of the aluminum block where the pulse line enters the engine This can occur if a short pulse tube was used First determine which tube is installed in your engine block The short pulse tube is 3/4" (19 mm) in length The long tube is 1-1 /2" (38 mm) in length If the long tube is installed in the block and the problem still exists, look for other engine problems If the short pulse tube is installed remove it and install a long tube P/N 6645373 BOBCAT FIELD MODIFICATION DATE: 15 October 1991 MODEL: 753 S/N 11001-13039; 853 S/N 11001-11324 SUBJECT: AUXILIARY HYDRAULICS MODULE DIRECT TO: CK"" CK"" CK"" D D D o NOTE: 	This Service Letter replaces Service Letter dated 9 May 1991 The 853 S/N range is revised Due to the possibility of ingress of moisture into the Auxiliary Hydraulics Module, a change of those components is necessary '  	New modules with improved sealing will be shipped to dealerships for replacement of the existing modules in the serial number machines listed above New modules will be marked with P/N 67006048 (for 753) or 65798808 (for 853) The Auxiliary Hydraulics Module is located as shown in figures 1 & 2 Please take immediate steps to have the new module installed on the affected serial number machine(s), per the enclosed Warranty Claim Form Melroe Company will give compensation for one-half (1/2) hour labor to replace the module on each affected machine One (1) additional hour is allowed for travel time for retailed units Printed in USA BOBCAT DATE: 16 October 1991 MODEL: ALL 50 SERIES SUBJECT: 6703046 HEATER KIT DIRECT TO: [X] [X] [X]  D      o      o      o      Mel roe Company has received reports of short term engine run-on with 50 series machines, when Heater Kit 6703046 is in use If this condition occurs, a 3 amp diode P/N 3675725 should be installed as shown Cover diode with shrink tubing to insulate it from chassis ground and provide weather proofing Current units have the diode installed It is not necessary to add a diode to these units The diode is shrink wrapped and can easily be identified The above is provided for technical information only Normal warranty policy applies B-13415 Printed in USA DIRECT TO: 00 BOBCAT [Kl 00 D      o      D---­D---­ DATE: 11 November 1991 MODEL: 220 EXCAVATOR (S/N 12000-13187) SUBJECT: HOURMETER CONVERSION A change was made on 220 Excavators after S/N 13187 so the hourmeter is activated only when the engine is running The hourmeter is now grounded by a new engine oil pressure switch The hourmeter on units S/N 13187 & Below is activated when the ignition key is in the on position If an operator forgets to turn the key to the off position, the hour meter will continue to run Parts are available which allow the hourmeter to operate only when the engine is running To convert machines listed above, order the following parts and install as shown The above is provided for technical information Normal warranty policy applies PARTS NEEDED: 6586423 HARNESS 1 ORIGINAL 6537501 SWITCH 1 FROM IGNITION SWITCH INSTRUCTIONS: i 1 	Disconnect the battery + 2 	Remove the existing engine oil Hourmeterpressure switch OIL PRESSURE SWITCH 3 	 Cut the connector off of the wire 4 	 Install the new engine oil pressure switch (P/N 6537501 ) CONVERTED 5 	S I h · · h" h FROM SPLICE nected to the old 011 pressure switch, to p ice t e existing ire, w 1c ws con- IGNITION SWITCH YELL/GR the yellow/green wire of the new har­ ness (P/N 6586423) HARNESS (6586423) YELL/BR 6 	Remove the wire from the (-)terminal of the hourmeter + 7 	Route the yellow/brown wire, from the OIL SWITCH c=J new 	harness, along side the main wire Hourmeter (6537501) · harness to the (-) terminal of the                       hourmeter Fasten with sta-straps Printed in USA DIRECT TO: [XI BOBCAT 00 [X] D      o      o      D---­ DATE: 	20 November 1991 MODEL: 	853 S/N 11979 & Above 853H S/N 11165 & Above SUBJECT: 	DRIVE BELT TENSION SPECIFICATIONS The drive belt tension specifications for 853 and 853H loaders has been changed The new specifications provide the proper tension in the drive belt system Machines which have serial numbers listed above, are factory set to the new specifications Machines which have serial numbers below those listed above, should be adjusted to the new specifications when in for any service This includes pre-delivery 853, 853H drive belt tension specifications: New Belt (less than 5 hours use) -14 Lbs Used Belt (more than 5 hours use) -12 Lbs If used belt tension is less than 10 Lbs, readjust to 12 Lbs The above specifications apply to the adjustment procedure in the Service Manual using special tools MEL-1404 and MEL-1406 The service manual will be revised to include the new tension specifications  Normal warranty policy applies Printed in USA DIRECT TO: BOBCAT 00  [X) 00 D      o      o      o      DATE: 12 December 1991 MODEL: ALL 753, 7753, 853 AND 853H LOADERS SUBJECT: LOW IDLE SPECIFICATION The low idle specification for the 50 series machines listed above has been changed to 1 , 150 RPM Machines are currently factory set to this specification Dealers are asked to make this revision to their service manuals and technical service guides All machines built previous to this specification change should have their low idle adjusted to 1150 RPM when being serviced T:he seal will need to be broken to change the low idle setting The RPM' s were increased to provide an optimum low idle setting to minimize vibration and noise The increase also provides more oil pressure at low idle and prevents intermittent EP-2 codes The above is provided for technical information Normal warranty policy applies DIRECT TO: BOBCAT 00 [X] 00 D       o        o        o        DATE: 13 December, 1991 MODEL: 753, 7753 SUBJECT: BROKEN AXLE REPLACEMENT Melroe Company has determined that some 753 and 7753 axles did not receive proper heat treatment There is no visual way to determine which axles are properly heat treated and no serial number break is available The heat treat problem has been corrected All axles being produced and those in our Chicago Parts Department are properly heat treated If an axle fails in the location shown, we recommend replacing all four axles to prevent further axle failures REPLACE ALL FOUR AXLES IF FAILURE OCCURS HERE ol I ,, The above is provided for technical information Normal warranty policy applies 'I; Printed in USA DIRECT TO: cY BOBCAT cY cY D D FIELD MODIFICATION D D DATE: 16 December 1991 MODEL: 753 (with 709 backhoe) SUBJECT: STOP DEVICE KIT# 6722099 Current production 709 Backhoe mounting kit (P/N 6538707) includes two bolt on stop devices These stops bolt to the underside of both lift arms They ensure that the backhoe mount doesn't contact the tubelines which are on the underside of the lift arms 	These stops are now available for installation onto existing 753 loaders which are equipped with 709 backhoes Melroe Company recommends installing these stops in all existing 753's which are equipped with 709 backhoe mounting kit (P/N 6538707) To make ordering these parts easier, they have been put into kit form Order kit (P/N 6722098) The instructions in the kit explain the correct installation procedure Melroe Company will give compensation for the cost of the kit and one (1) hour labor for installation One (1) additional hour is allowed for travel for retailed machines Parts list -kit # 6722098 6586470 STOP 2 73G-620 SCREW 2 6722099 INSTRUCTIONS 1 Printed in USA DIRECT TO: BOBCAT 00  [XI 00 o      o      o      o      DATE: 	17 December 1991 MODEL: 	753 S/N 15767 & ABOVE 7753 S/N 11221 & ABOVE SUBJECT: 	DRIVE BELT TENSION SPECIFICATIONS The drive belt tension specifications for 753 and 7753 loaders has been changed The new specifications provide the proper tension in the drive belt system Machines which have serial numbers listed above, are factory set to the new specifications Machines which have serial numbers below those listed above, should be adjusted to the new specifications when in for any service This includes pre-delivery 753, 7753 drive belt tension specifications: New Belt (less than 5 hours use) -15 Lbs Used Belt (more than 5 hours use) -12 Lbs If used belt tension is less than 8 Lbs, readjust to 12 Lbs The above specifications apply to the adjustment procedure in the service manual using special tools MEL-1405 and MEL-1406 The service manual will be revised to include the new tension specifications The above is 	provided as technical information Normal warranty policy applies Printed in USA DIRECT TO: []f" BOBCAT []f" []f"  D D D D DATE: 5 January 1990 MODEL: Angle Broom (Model 5708) SUBJECT: Interference With Hose guard Loop on Model 843 Bob-Tach frame and hose loop interference problem can be corrected as follows (Figure 1, Item 1 ) Use a cutting torch to cut away material at the left side mount on the broom mounting frame, per dimensions shown in figure 2 This will allow additional clearance for the hydraulic hose loop Pl-2566 Figure 1 Figure 2  only Printed in USA DIRECT TO: CH"" BOBCAT !lr" !lr"  D D D D DATE: 18 June 1990 MODEL: T305 TRENCHING ATTACHMENT SUBJECT: Boom Frame The lower mainframe plate for the boom has been shortened on present production units (Figure 1) This was done to prevent possible interference of the plate with the mount on the power unit when raising the boom out of the trench The plate can be shortened on earlier built (Serial Number 0490 & below) trenching units, if desired To 	Shorten The Plate: 1 	Remove the trenching attach­ment from the Bob-Catch 28 mount (71,1) 2 	Follow the dimension shown in ' 	---i' ii hI figure 1 to mark the portion to I 203 be 	cut off 788 ::I I (516) 3 	Use an acetylene torch to cut (200,1 away the portion, as marked 934 (237,2) 4 	Sand or grind the cut area and B-13293 repaint as necessary Figure 1 The above is provided as product improvement information only l\Jo warranty is allowed Printed in USA DIRECT TO: rn""' BOBCAT rn""' rn""' D D FIELD MODIFICATION DATE: 22 June 1990 MODEL: 3022, 3023 SUBJECT: Flywheel Counterbore Dial Indicator Check Concerning the recent Field Modification , dated 16 April 1990, subject: "Engine Mounting Plate, Flywheel & Drive Adapter", instructions were given to check flywheel counterbore concentricity The purpose of this check was to measure the concentricity of the counterbore only NOT the flat surface of the flywheel Proper effort must be made to position the stylus of the dial indicator against the peripheral wall of the counterbore circle, and NOT touching the flat mounting surface at the base of the counterbore (Please refer to Figure 1 for detailed view) Set the indicator dial at Zero and put a reference mark on the flywheel when beginning The indicator should return to Zero after rotating the flywheel a full 360 degrees The concentricity reading of the inside diameter should be within 003" (0,08 mm) Total Indicated Reading Remove the four glow plugs from the engine to make it easier to rotate the crankshaft Also, pull forward on the cooling fan when turning the crankshaft to prevent end movement which might affect concentricity reading DO NOT replace the flywheel unless, after repeated checks, the flywheel is found to be defective B-13308 Figure 1 DIRECT TO: CH"" BOBCAT CH"" CH"" 0 0 0 0 DATE: 12 July 1990 MODEL: T208, T116 SUBJECT: Digging Chains Product improvement changes were made to the chain and tooth design for the trencher models listed above Parts ordering configuration is also changed Mounting bolt hole location for the cutter teeth was changed from 1" to 1654" on the 1654" pitch digging chains The new cutter teeth will have hole spacing arrangement so as to fit both old style and new style digging chains The old teeth will NOT fit on the new chain 6655760 LH 6633363 LH RENT 6655759 RH 6633364 RH 1"j -L 1654" 1· 1654" The double standard digging chains are an Anti-Back Flex (ABF) with heavy side plates New spacers are used with the ABF double standard chain The T208 and T116 model trenchers now come standard with a single standard chain of 50 pitches for a 24" digging depth Factory option for these machines will be the 50 pitch double standard ABF chain for 24" digging depth To increase digging depth to 30" or 36", add the 8 Pitch Kit(s), as listed on Page 2 Also needed is the chain guide kit indicated The 48" digging depth kit is offered as a field accessory, for the T116 only The single standard 84 pitch chain will be the only chain available for the 48" boom New Part Numbers are: 6655754 50P ABF (OS) 24" 6655753 BP ABF (OS) 6655834 84P SS 48" 6655833 50P SS 24" 6655832 8P SS (1 for 30", 2 for 36") 6702160 Kit, Spacer 6''8" 6702441 Kit, Chain Guide (30''36") 6701917 Kit, 24-36 Carbide 6701918 Kit, 24-36 Cup 6701919 Kit, 24-36 Carbide/Cup DIRECT TO: BOBCAT CB""'  CB""' CB""' D D D D DATE: 17 July 1990 MODEL: 3022, 3023 & T305 SUBJECT: Quick Coupler Change The following coupler changes were made to present production trencher power units and the digging attachment: On The Power Unit The motor case drain male coupler (6648969) and cap (1513549) on the manifold block were replaced by female coupler (6648967) and plug (1519324) On The Digging Attachment Motor case drain female coupler (6648967) and plug (1519324) were replaced by male coupler (6648969) and cap (1513549) These changes were made to prevent connecting the motor case hose to pressured coupler in the manifold, which could result in damage to the motor When installing an older digging attachment on a new power unit the female coupler installed on the case drain hose will have to be replaced by a male coupler  only Coupler DIRECT TO: BOBCAT CB""' rn-"'  CB""' D D D D DATE: 18 July 1990 MODEL: 220 Excavator SUBJECT: Grease Fitting For Track Tension Cylinder The grease fitting 12H-5, for the track tension cylinder has now been replaced by 6655752 Field reports have indicated a problem with the track cylinder not holding tension due to the fitting, 12H-5, not holding the pressure This change become effective starting with machine S/N 12155 Grease fitting, 6655752, has a recessed ball to improve sealing and prevent leak down This fitting is available from Melroe Parts Marketing The above is provided as product improvement information only B-13091 DIRECT TO: BOBCAT  D D D D DATE: 26 July 1990 MODEL: 2400, 2410 SUBJECT: Axle Repair Procedure NOTE: 	THIS SERVICE LETTER REPLACES SERVICE LETTER DATED 26 MARCH 1990, SUBJECT: "AXLE HUB REPAIR (2400 SERVICE MANUAL 6570737)" The following procedure must be used during reassembly of the axle and drive gear Refer to the Service Manual (6570737) Page 4-14, for disassembly and reassembly instructions -After installing the gear and bearing and prior to installation of the retention bolt and washer, (Page 4-14, Figure C) thoroughly clean the bolt and bore threads with thread cleaner (LocTite Primer "T" or Primer "N") Use air pressure to blow-dry the threads For axle with 625" UNF thread use thread locker (LoTite #680) and fill the bolt hole in the axle to 17" (43 mm) from the top of the washer For axle with metric thread fill hole to 12" (40 mm) from top of washer Install the bolt and washer and tighten to the correct torque: Tapered Head Bolt 200 ft-lbs (271 Nm) Hex Head Bolt 240 ft-lbs (325 Nm) The Service Manual will be revised to include the above information 1 7" 12" (43 mm) (40 mm) 625" UNF Metric Thread Thread B-13266 Printed in USA DIRECT TO: ar" BOBCAT ar" rn""' D D D D DATE: 	3 August 1990 MODEL: 	641, 643, 741, 743, 743DS, 843, 943, 974, 980, 1600 and 2400, 3023 SUBJECT: 	Gear Reduction Starter NOTE: This replaces dated 7 December 1989 Bobcat loader models listed above now have model 28MT Delco gear reduction starters installed on the engine The Delco model 22MT and 27MT starters are no longer available, except as remanufactured units The new gear reduction starter directly replaces the old starter A new starter support bracket is used with the new starter on the Model 643, and 843 Loader (W/lsuzu engine) When installing the gear reduction starter on earlier Model 643 or 843 Loader (W/lsuzu engine) the following parts will also be needed; Model P/N Desc Oty 643 6701847 Bracket 1 843 6701618 Bracket 1 843 6701628 Spacer 1 843 5CM-1016 Screw 1 843 5CM-1030 Screw 1 I' - Service parts for the old starters will continue to be available from Melroe Parts in Chicago Only complete starters will be offered as parts replacement for the new starter If starter failure occurs, replace the failed starter and hold it for return authorization Normal warranty procedure must be followed \ ,r­ DIRECT TO: BOBCAT !Y  !Y IY D D FIELD MODIFICATION ° D DATE: 13 August 1990 MODEL: 3022 S/N 11024 and Below; 3023 S/N 11357 and Below (TRENCHER) SUBJECT: Two-Speed Switch The two-speed switch, 6651144, has been replaced by an improved switch, 6655805, on present production power units The new switch is designed to perform better in a severe dust environment The improved switch, 6655805, can be ordered from Melroe Parts at Chicago and installed on prior built machines, as desired Melroe Company will give compensation for the cost of the switch plus 1/2 hour labor for installation One (1) additional hour is allowed for travel time for retailed units DIRECT TO: BOBCAT cY  cY cY D D D D DATE: 10 October 1990 MODEL: 220 Excavator SUBJECT: Brakes Standard Hydraulically activated brakes are now a standard feature on S/N 12286 & Above Model 220 Excavator track drive system The brakes are automatically engaged whenever the drive levers are in neutral position Service Manual and Parts Fiche are being revised The above is provided as product improvement information only Printed in USA DIRECT TO: BOBCAT cY  Dl""" Dl""" D D D D DATE: 14 November 1990 MODEL: All Loaders SUBJECT: Tire Inflation To help assure stability during transport of machines, Bobcat loader tires are factory inflated to 50-55 PSI The Loader Arrival Condition Report directs attention to this fact The following statement appears on the report, under the heading "OPERATION AND DRIVE SYSTEM" ie; "Machines are shipped with factory tire pressure settings Consult your Service Manual or Technical Service Guide and adjust to correct operating pressure before delivery to the customer" Melroe Company does occasionally receive a report from dealers that "tires are found to be overinflated" upon delivery to a dealership Dealers are reminded that the tires are purposely inflated to the higher pressure for the reason stated above and that it is necessary for the tires to be deflated to the correct pressure specification when performing the Arrival Condition Inspection of the machine  only Printed in USA DIRECT TO: cY BOBCAT cY cY  0 0 SAFETY NOTICE 0 0 DATE: 	12 November 1990 MODEL: 	543 Thru 743 OS Bobcat Loaders Equipped With Cab Heater Kit, P/N 6564520 SUBJECT: 	Insert, P/N 6516296 Red Dot Heater Plumbing Kit P/N 6564520, includes four (4) inserts, P/N 6516296, that are installed on the quick couplers used in the cab heater coolant plumbing circuit Melroe engineering specifications require that the four (4) inserts be solid brass However, it has been reported that Red Dot Corp has supplied a two-piece soldered assembly which does not meet Melroe's engineering specifications If the insert breaks and separates at the soldered joint, hot liquids could escape and cause serious burn injuries to the operator or other persons near the installation Figure A below shows the correct solid brass insert Figure B below shows the incorrect two (2) piece soldered assembly CORRECT INCORRECT (Solid Brass) (Two-Piece Soldered Joint) The Melroe Company requests that all Red Dot brand Heater Plumbing Kits, P/N 6564520, in parts inventory be inspected If any of the two-piece soldered inserts are found, they must be replaced with a solid brass insert, which will be provided at no charge by the Mel roe Company All two-piece inserts should be returned to the Melroe Company Service Department, so that we can provide warranty compensation to you and in turn receive compensation from Red Dot Dealers are asked to inspect all customer machines and any machines in current dealer inventory, which have the Red Dot brand Heater Plumbing Kits P/N 6564520 All two-piece soldered inserts found must be replaced This notice applies only to this particular plumbing kit, and not to other kits manufactured by Red Dot or by others The Melroe Company will compensate for one (1) hour labor for replacement of fittings on each affected machine One (1) additional hour in allowed for travel time for retailed machines -2­ DIRECT TO: BOBCAT c::Y  W W 0 0 0 0 DATE: 15 November 1990 MODEL: Melroe Auger SUBJECT: Bolt Change for Replacement Teeth Replacement teeth for the Earth Auger are now shipped with one-half inch carriage bolts and lock nuts for mounting P/N 6651555 	Tooth Assembly, includes Bolt (10C-820) & Nut, Self-Locking (850-8) Formerly, 3/8" bolts, with split washers and 3/8" nuts, were used for mounting teeth to the auger When replacing teeth which used a 3/8" carriage bolt, it is necessary to do the following: 1 Drill out (or ream) the 3/8" bolt hole to 1/2" diameter NOTE: Do not oversize the hole as a snug fit is desired only Printed in USA DIRECT TO: cY BOBCAT cY cY  0 0 0 0 DATE: 16 November 1990 MODEL: 2400, 2410 SUBJECT: High Pressure Drive Motor Hoses To improve service reliability, the following changes were made to the drive motor high pressure hoses on present production machine: Hose 6531260 is replaced by 6&37908 Hose 6531259 is replaced by 6537909 Tubeline 6584658 is replaced by 6537910 Fitting 55E-16 is replaced by 52E-16 These changes became effective starting with machine serial number 12165 ! The old hoses and tubeline are no longer available as service parts If an order is made for any of them, a complete set of replacement parts will be shipped instead The above is provided as service improvement technical information only Normal warranty policy applies Printed in USA DIRECT TO: cY BOBCAT cY cY 0 0 0 0 DATE: 19 November 1990 MODEL: 225 Excavator SUBJECT: Grease Fittings for Slew Ring The Model 225 Excavator is shipped from the factory without the two grease fittings for the slew ring installed The two grease fittings for the slew ring are contained in a plastic bag and placed in the tool compartment, prior to shipment The fittings are not installed during factory assembly because they may get broken when handling the machine with a forklift The fittings must be installed when the Pre-delivery Inspection is performed on the machine The above is provided as service information only Printed in USA DIRECT TO: cY BOBCAT cY cY D D D 0 DATE: 4 December 1990 MODEL: 753 SUBJECT: LOW FUEL Service Code When the fuel tank level becomes low, the service code "FUEL 2" will appear on the instrument panel display monitor, and three audible "Beeps" will he heard If the fuel tank is not immediately filled, a second warning symbol, "b 22" will appear after ten minutes time has passed The second symbol is an error code and is an inherent feature of the operating system unit used in early model 753 loaders The display will return to normal operation after the fuel supply has been replenished This low fuel error code condition is being corrected by the manufacturer of the operating system control unit Printed in USA DIRECT TO: BOBCAT c:Y  W W D D D D DATE: 5 December 1990 MODEL: 3022, 3023 SUBJECT: Adhesive for Traction Drive Motor Mounting A high strength adhesive is applied to the mounting face of the traction drive motor before it is installed on present production trencher power units The adhesive helps prevent movement of the motor If the motor has been removed for servicing, re-apply adhesive, part number 6658962, (LocTite 680) to the clean and dry mounting face of the motor before installing it on the chaincase Clean the mounting screws and threads in the mounting holes on the chaincase Apply adhesive (6658962) to the threads before installing Tighten the screws to 65-70 ft-lbs (88-95 Nm) torque  only Printed in USA DIRECT TO: cY BOBCAT cY cY  	D D FIELD MODIFICATION D D DATE: 	3 April 1989 MODEL: 	2400 MTC SUBJECT: 	-Two Speed Solenoid Change -Supplemental Hydrostatic Charge Fluid -Removal of Pedal Housing Boot An improved two speed solenoid valve (6652532) is being installed on present production machines, beginning with machine serial number 11256 (Domestic) The improved solenoid uses a coil which has a higher voltage rating for longer service life Earlier built machines (serial numbers 11255 and below) must also be equipped with the new coil, which is being shipped to dealerships as part of this Field Modification program A bypass hydraulic hose has been added to present production machines to provide supplemental charge fluid to the hydrostatic pump replenishment loop The supplemental charge fluid assures positive pressure in the replenishing loop to prevent stalling during bucket loading operation This change became effective with machine serial number 11279 (Domestic) and 50023 (Foreign) All prior built machines will be equipped with the supplemental charge bypass hose installation Parts are being shipped to dealerships for Field Modification of machines below serial number 11278 and-50022 The rubber boot under the housing for the drive control pedal must be removed and discarded Printed in USA Procedure to remove the pedal housing boot: 1 	 Remove the front floor panel 2 	 Remove the mounting bolts for the pedal control assembly 3 	 Remove the pedal control assembly 4 	 Remove the rubber boot from the bottom of the control assembly housing 5 	 Reinstall the control assembly and front floor panel Procedure to install two speed coil: 1 	 Remove the retaining nut on the solenoid (Figure 1) 2 	 Lift off shield and existing coil Unplug the wire connectors (Figure 2) 3 	 Install new coil Plug the connectors together 4 	 Tighten the retaining nut Procedure to install the bypass charge hose: 1 	 Remove the plug below the centering assembly at the hydrostatic pump (Figure 3) 2 	 Install the long fitting 16K-5 3 	 ·install the 90 degree swivel elbow on the long fitting 16K-5 4 	 Install the hose assembly, 6652065 5 	 Remove the bolts holding the high pressure hose flange on the hydrostatic motor Discard the bolts (Figure 4) 6 	 Install the block fitting, 6533216, between the flange and motor Be sure 0-rings, 58K-219, are in place, on on each side of the block fitting Install the longer bolts, 1C-744, and tighten securely 7 	 Install the 45 degree elbow on the block fitting 8 	 Connect the end of the hose assembly, 6652065, to the elbow After operating the machine, check for leaks -2­ Melroe will give compensation for one-half hour (30 minutes) labor to install the solenoid coil, and one (1) hour to install the bypass hose and parts One-half hour (30 minutes) is allowed for removal of the boot One (1) additional hour is allowed for travel time for retailed machines Figure 1 Figure 2 Figure 3 Figure 4 -3­ ai ) ;, ·' I I DIRECT TO: rn-' BOBCAT rn-' rn-' D D D D DATE: 11 August 1989 MODEL: 100 Excavator (S/N 11000 & 12000) SUBJECT: Modifying the Boom/Arm Pivot Breakage of the boom/arm pivot pin, 6638901, can be prevented by modifying the pivot bushing housing, replacing the old bushings, installing a grease fitting and using a new solid core pin instead of the cross drilled pin Order these parts from Chicago: Part No Description 	Oty 6651699 Pin 1 (Replaces 6638901) 6651700 Bushing 2 (Replaces 6638896) 6637533 Seal 2 36H-35 Grease Fitting 1 Repair Procedure: 1 	 Remove the bucket and bucket cylinder from the arm Remove the arm cylinder pin 2 	 Disconnect the hoses Remove pivot pin 6638901, and remove the arm 3 	 Drive-out the old bushings and seals 4 	 Drill a 230 inch hole for the grease fitting in the bushing housing (Figure 1) 5 	 Use a press to install the 6651700 bushings in the pivot housing Install the seals (Do Not use a hammer to install the bushings) Printed in USA 6 Install the grease fitting 7 Install the arm onto the boom and install the pin, cylinder, etc 8 Add grease to the fitting until it shows at the dust seals The above is provided as service information only No warranty is allowed 8-13208 Figure 1 -,  DIRECT TO: rn' BOBCAT rn' rn' D D D D DATE: 29 August 1989 MODEL: 2400 SUBJECT: Restrictors For The Tilt Hydraulic Circuit A dump restrictor can be installed in the tilt hydraulic circuit to slow down the tilt hydraulic function The tilt dump function needs to be slowed down when using an attachment which may subject the loader to heavy loads A restrictor kit has been added to the parts supplied with the Fertilizer buckets and the Industrial Grapple attachments (Kit number 6532606) Two types of restrictors are available They are both included in kit number 6532606 Machines, S/N 11304 & Above, have a threaded port in the tilt dump port of the control valve Use the following parts for these machines Part No Description Oty 6592649 RESTRICTOR 1 9593680 RETAINER 1 Earlier serial number machines do not have a threaded port in the tilt port Use the following parts for these machine Part No Description Oty 6653685 RESTRICTOR ASSY 1 12K-7 FITTING, 45 Degree, W/0-ring 1 Instructions, 6570922, are included in the kit  only No warranty is allowed Printed in USA DIRECT TO: []" BOBCAT []" []" D D D D DATE: 7 September 1989 MODEL: 843 (Isuzu Engine) SUBJECT: Engine Head Gasket, 6631756 Because of a vendor part number error, wrong cylinder head gaskets were stocked at Melroe Parts Sales Some of these gaskets were shipped to dealerships Correct and incorrect gaskets are shown below: B-13067 Dealers are requested to check their stock Return all incorrect individual head gaskets 6631756, top gasket kit 6631949 and overhaul kit 6647664, intact and unopened to Melroe Parts Sales in Chicago Return the parts w ith a completed shipping discrepancy report for proper credit Order new gaskets or kits as needed to replenish stock Printed in USA DIRECT TO: BOBCAT cY  cY rn' 0 0 0 0 DATE: 11 September 1989 MODEL: 2400 SUBJECT: Relay Kit For Cab Heater A relay kit is available which, when installed, will eliminate the engine stopping delay that sometimes occurs when turning the ignition switch off The delay in stopping happens if the heater switch is left on while turning the ignition switch off to stop the engine The heater motor then acts as a generator and provides some voltage to the fuel solenoid, which delays its' shutting off The relay kit installed in the heater circuitry opens the circuit as soon as the ignition is turned to the off position The kit, part number 6534411, can be ordered from Melroe Parts Department Installation Instructions, 6720136, are included in the kit The above is provided as service information only Printed in USA DIRECT TO: !ll""" BOBCAT lll""" lll"""  D D FIELD MODIFICATION D D DATE: 13 October 1989 MODEL: T305 Digging Attachment (S/N 228 & Below) SUBJECT: End Roller For Digging Chain An improved end roller is now installed on the present production T305 digging attachments (S/N 229 & Above) The end roller, part number 6576138, and spacers, part number 6577290, are designed to keep dirt out of the bearing area and extend its operating life The improved end roller (6576138) is available at Chicago Parts for replacement on failed units in the field Mel roe will give compensation for the cost of the end roller for replacement of an early type end roller which has failed One hour labor is allowed for replacement time One additional hour is allowed for travel time for retailed units DIRECT TO: cY BOBCAT cY cY D D D D DATE: 	23 October 1989 MODEL: 	641, 643, 741, 743, 743DS, 843, 943, 974, 980, 1600 and 2400, 3023 SUBJECT: 	Gear Reduction Starter Bobcat loader models listed above soon will have model 28MT Delco gear reduction starters installed on the engine The Delco model 22MT and 27MT starters will no longer be available The new gear reduction starter directly replaces the old starter The starter support bracket is not used on the new starter Service parts for the old starters will continue to be available from Melroe Parts in Chicago Only complete starters will be offered as parts replacement for the new starter If starter failure occurs, replace the failed starter and hold it for return authorization Normal warranty procedure must be followed DIRECT TO: BOBCAT []""  []"" []"" 0 0 0 0 DATE: 6 December 1989 MODEL: 3022, 3023 SUBJECT: Mounting Position of Digging Unit In order to facilitate loading of trencher power units for transport from Melroe, the digging attachment is mounted in the maximum offset position (Right-Hand Hooks) The normal digging position is centerline mounted, using the left-hand hooks Therefore, prior to retailing the unit, remove the digging attachment from the right-hand hooks and install it on the left-hand hooks (Refer to the Operation & Maintenance Manual for mounting procedure) Unless otherwise requested, the trenching unit should always be delivered centerline mounted  only No warranty is implied Printed in USA DIRECT TO: []"" BOBCAT IY !,;,/ IY / D D D D DATE: 7 December 1989 MODEL: 	641, 643, 741, 743, 743DS, 843, 943, 974, 980, 1600 and 2400, 3023 SUBJECT: 	Gear Reduction Starter NOTE: This replaces dated 23 October 1989 Bobcat loader models listed above soon will have model 28MT Delco gear reduction starters installed on the engine The Delco model 22MT and 27MT starters will no longer be available The new gear reduction starter directly replaces the old starter A new starter support bracket is used with the new starter on the Model 643 and 843 Loader When installing the gear reduction starter on earlier Model 643 or 843 Loader the following parts will also be needed; Model P/N Desc Oty 643 6701847 Bracket 1 843 6701618 Bracket 1 843 6701628 Spacer 1 843 5CM-1016 Screw 1 843 5CM-1030 Screw 1 Printed in USA / r Service parts for the old starters will continue to be available from Melroe Parts in Chicago Only complete starters will be offered as parts replacement for the new starter If starter failure occurs, replace the failed starter and hold it for return authorization Normal warranty procedure must be followed DIRECT TO: []""' BOBCAT []"" []""'  D D D FIELD MODIFICATION D DATE: 11 December 1989 MODEL: 905A, 905B Backhoe SUBJECT: Restrictor Orifice for Swing Cylinder A restrictor Orifice is available which can be installed in the backhoe control valve, swing cylinder port, to slow the boom swing function Too fast boom swing function can cause broken chain links Installing a restrictor orifice will help prevent this from happening If broken chain links are recognized as a problem, order Orifice, P/N 6655091, which is available from Melroe Parts at Chicago Install the restrictor in the control valve, swing cylinder base port Melroe will provide warranty compensation for the above, and will honor claims submitted for 905 backhoes exhibiting this problem Printed in USA DIRECT TO: Dr"' BOBCAT D Dr"'  D D D D DATE: 	29 January 1988 MODEL: 	4408, Serial Number 14432 & Above · 443, Serial Number 12717 & Above SUBJECT: 	Utility Fork Mounting Frame Interference With Bob-Tach Lever The lever for the locking wedges for the currently designed Bob-Tach travels a longer arc when it is pulled up Therefore, an interference may exist between the lever and top flange of the mounting frame on older /"' 	Utility Forks To correct this situation, remove the hose clamp and widen the slot to 138" (3514 mm) (Figure 1 ) Move the hose clamp location to location shown in figure one Slot For r-----:1380'' ------------2600"-----------I (665 mm) Figure 1  only Printed in USA DIRECT TO: BOBCAT D D D D DATE: 11 April 1988 MODEL: T135, T136 and Midmark 332 SUBJECT: Hydrostatic Hose Protection Present production Trenchers now have protective moulding installed in the frame openings for the hydraulic and hydrostatic hoses The moulding will prevent chafing damage to the hoses The moulding can be ordered and installed on earlier built machines, if desired Part number for the moulding is: (Bulk: order by feet), 6630138 Feet needed per machine is two The above is provided as product improvement information only No warranty is allowed DIRECT TO: rn-" BOBCAT rn-" rn-" D D FIELD MODIFICATION D D DATE: 25 April 1988 MODEL: 56 Excavator (Serial Numbers 12001 Through 12036) SUBJECT: ROPS lD Plate and "Melroe" Decal The ROPS identification plate is installed at the wrong location and must be removed from the serial number Excavators listed above (Fig 1, Item 1 ) A new lD plate must be installed at the location shown below (Fig 2) A " Mel roe" decal must be installed at the location where the old lD plate formerly was installed (Fig 3) ROPS lD plates and "Melroe" decals have been sent to your District He will arrange to have the plates and decals installed during his visit to your dealrship 4 72" 1811" (120 mm) l:       2 56" I (460 mm) 138" Fig 2 Fig 1 (35 mm) c1­ l       ,  ll&7JIOE­ 59" ,15 mm) Fig 3 Printed in USA DIRECT TO: []"' BOBCAT D []"' D D D D DATE: 26 April 1988 MODEL: Bobcat Sweeper SUBJECT: "Zig-Zag" Broom Bristles When installing the poly zig-zag or wire zig-zag bristles on the broom drive tube, use the following procedure: 1 	 Put a straight (flat) bristle at the end of the tube 2 	 Install the zig-zag bristle as shown in figure one 3 	 Make sure that the guide tabs (item one) do straddle the bars on the tube and that each bristle is aligned 180 degrees apart on the rollers, figures one and two 4 	 Finish the assembly with another straight (flat) bristle at the other end of the tube The 	above is only provided as service information Figure 1 	Figure 2 Printed in USA DIRECT TO: BOBCAT ar"  ar" D D D D D DATE: 27 April 1988 MODEL: 1213 Feller Buncher SUBJECT: Engine Replacement Engine, part number 6631 582, is no longer available as a service replacement engine The model 843 engine, part number 6631668, will now serve as the service replacement engine for the model 1 21 3 Feller Buncher Before installing engine 6631668, the fuel injection pump must first be calibrated to model 1213 engine specifications This must be done by an authorized Diesel Kiki Service Agency ' Give the following information to the Diesel Kiki shop, along with the fuel injection pump All Diesel Kiki shops have the necessary calibration data available Engine: 4JB1PK (Isuzu) Injection Pump: 894404-0320 (Isuzu) (Part Number) 104741-1190 (Diesel Kiki) Pump removal and installing procedures are explained in the 1213 Service Manual, 6570156 DIRECT TO: rn' BOBCAT D rn' D D D D DATE: 29 April 1988 MODEL: 642B and T135 SUBJECT: Choke Adjustment and Starting Procedure NOTE: 	This Service Letter replaces Service Letter, same subject dated 10 February 1987 To insure proper startup of the engine the choke must be fully closed during cranking Check the choke operation as follows: 1 	 Relieve the spring tension by hooking the spring to the first (least tension) post (Fig 1 ) 2 	 Hold the choke lever closed and check the choke plate (butterfly) to see that it is tightly closed (Fig 2) Fig 1 	Fig 2 -1-	Printed in USA 3 	 If the plate is not tightly closed, loosen the two screws on the plate (Fig 3) 4 	 Tap the plate shaft in, then tighten the plate screws (Fig 4) Fig 3 	Fig 4 5 	Re-check the choke operation If it still does not close tightly, remove the plate screws and plate Elongate the holes in the plate and reinstall it Repeat step four (Fig 5) Fig 5 6 	Leave the spring fastened to the first post When starting the engine, stroke the throttle lever several times, then set it at the 1/2 position This gives the engine an initial injection of new fuel for fast starting The 	above is provided as technical information only DIRECT TO: BOBCAT C1t"'  C1t"' C1t"' D D D D DATE: 	16 June 1988 MODEL: 	T135 -Serial Numbers 11045 and below T136 -Serial Numbers 12269 and below SUBJECT: 	Front Axle Pivot Reinforcement Kit (6578451) The front axle pivot has been revised on present production T135 and T136 Trenchers Material has been added to the weldment to make it stronger The new axle pivot, 6578448, replaces pivot, 6577803 A grease fitting has been added to the tube A kit is available which can be installed on earlier built Trenchers The kit includes two reinforcement plates which must be welded to the existing pivot assembly The kit part number is 6578451 and can be ordered from Melroe Parts Marketing in Chicago Installation Instructions are provided with the kit  only No warranty is allowed Figure 1 -Pivot Assembly BOBCAT --' , ,rl: r SAFETY NOTICE  f' ""'  FIELD MODIFICATION DATE: 5 August 1988 MODEL: T116 (S/N 11001Through11565) SUBJECT: Control Rod and Pintle Lever Replacement I  ,""1 f ? DIRECT TO: Cil""" Cil""" Cil""" 0 0 0 0 The bolt holding the rod end swivel to the pintle lever on the hydrostatic ·pump can rub and wear a hole in the fuel tank This could result in fuel leaking out ,· To prevent this from occuring the linkage has been revised to give more · clearance beteen th rod end and the fuel tank The old control rod and lever on all prior built T116 Trenchers in the serial number range listed above must be replaced Melroe will ship the following parts to dealerships which have affected machines in their territory Part Number Description 6579221 Rod, control 6579222 Lever, pintle Remove the old parts and install the new parts (Refer to Service Manual, 6570505, for procedure) Melroe Company is notifying owners of affected machines A copy of the letter is attached / I ! I I I Printed in usA machines so that the new linkage parts can be installed Melroe will give compensation for one ( 1 ) hour labor to install' the parts One (1) additional hour is allowed for travel time for retailed machines , I t DIRECT TO: rn"" BOBCAT rn"" rn"" D D D D DATE: 10 August 1988 MODEL: Trenchers SUBJECT: Dust Prevention For Gauges Gauges sometimes may become inoperative due to dust accumulation from operating the Trencher in severe dust applications To prevent dust from entering gauges, use RTV rubber sealant to close the drain hole located at the underside of the gauge, when installing a new gauge (Figure 1) Gauges are properly vented to prevent moisture accumulation The above information is provided as technical information only Figure 1 Printed in USA DIRECT TO: BOBCAT D D D FIELD MODIFICATION D DATE: 11 August 1988 MODEL: T135 and T136 Trencher Digging Unit SUBJECT: Reduction Gearbox Breather Federal or Hub City brand reduction gearcases installed on earlier built Trencher digging units have a "sintered brass" plug for a breather, located at the top of the gearcase Present production digging units have the "button" type breather, 6632601, with reducer, 19F-2, installed instead of the brass plug type breather The button type breather is to be installed on gearcases which have the sintered plug, to prevent water from entering the gearcase Order the breather and reducer from Melroe Parts in Chicago Melroe Company will give compensation for the cost of the breather plus one-half ( 1 /2) hour labor for installation One ( 1) additional hour is allowed for travel time for retailed machines Printed in USA DIRECT TO: CB"" BOBCAT CB"" CB"" D D D D DATE: 	15 August 1988 MODEL: 	T116 -Serial Numbers 11539 through 11552 and S/N 11 560 & Above SUBJECT: 	Heavy Duty Air Cleaner The larger capacity air cleaner is now a standard feature on the T 116 Trencher, effective with the serial numbered machines listed above Service parts information can be found on grid 020 of your T116 parts fiche, 6570495, dated June 1988 The above is 	provided as parts technical information DIRECT TO: Dr BOBCAT Dr Dr 0 0 0 FIELD MODIFICATION o DATE: 17 August 1988 MODEL: T135 and T136 SUBJECT: Rock Guard for Rear Differential A rock guard for the rear differential is installed on present production T135 and T136 power units All new T135 and T136 Trencher power units retailed after 1 January 1988 should be equipped with the rock guard, in support of the 6/24 Extended Warranty program The rock guard (Kit #6577075) can be ordered from Melroe Parts Marketing at Chicago Please order and install the rock guard, accordingly for machines sold after 1 January 1988, which do not have the guard installed Melroe will give compensation for the cost of the kit plus one ( 1) hour labor for installation One ( 1) additional hour is allowed for travel time for the retailed machines DIRECT TO: ar' BOBCAT ar' ar' D D D D DATE: 	4 November 1988 MODEL: 	T135 -Serial Number 11042 & Below T136 -Serial Number 12196 & Below SUBJECT: 	Steering Motor Leak A leaking steering motor may be due to high gear pump pressure Before attempting to repair a leaking steering motor by resealing, first check the pump relief pressure Refer to Service Manual, Pages 3-5 and 3-6 for procedure If relief pressure is found to be excessive (above 2300 PSI) the relief valve should be replaced by the new cartridge type relief valve and end plate Part number 6647427 includes new end plate with cartridge relief valve If relief pressure has greatly increased (3000 PSI or higher) the pump may be damaged internally, in which case a complete gear pump must be installed  only HYDRAULIC PUMP :e--ccoeG-®   J Pin Type Relief Valve I LG-C®-0 «rO ' Cartridge Type Relief Valve (Current Models) Printed in USA DIRECT TO: BOBCAT CB""' Serviceletter D D D D DATE: 9 November 1988 MODEL: 440, 4408, Farmboy and 443 , SUBJECT: Hydraulic/Hydrostatic Buzzing Noise auzzing noise in the hydraulic/hydrostatic system may be caused by one or more of the following conditions (See "Service News For Today", dated November 1987) 1 Cold Oil 2 Filter Needs Replacement 3 Air In System If correction of the above conditions does not eliminate the problem, replacement of the 120 PSI bypass valve spring (8) may be necessary Install new 150 PSI spring, part number 6532403, in place of spring 6565324 Check the charge pressure It should be 80 to 85 PSI with a maximum reading of 95 PSI If a higher than 95 PSI reading is noted, lower it to 80 -85 PSI by drilling the (A) fitting that holds the charge pressure spring in place For every seven PSI too high, drill the fitting deeper by 060" EXAMPLE: 105 PSI (charge pressure) 80 PSI 25 PSI · (over pressure) -;-7 3,57 x 06" o:ii 4" (drill deeper) , rr Present production 440 series Bobcats hav·e th higher PSI rated spring - installed · ·· only' E-1711 ' -2­ DIRECT TO: Dr" BOBCAT Dr" Dr"  D D FIELD MODIFICATION ° D DATE: 17 June 1987 MODEL: 843 S/N 24001 and Above SUBJECT: Injection Timing on Isuzu Engines If the 843 Isuzu engine has any of the following symptoms, incorrect injection timing may be the cause: A White exhaust smoke during high idle B Engine runs erratically during high idle C Some apparent lack of power If any of these conditions are present, check the timing, using the procedure described in section 7C of the Service Manual (6566091 ) Use tool MEL-1201 to do the procedure Correct injection pump timing is 16 degrees BTDC The dial indicator must read 0020 -0022" (0,508 -0,559 mm) [ID Melroe will give warranty compensation per the current Service Policy and Procedure Manual Printed in USA DIRECT TO: ar" BOBCAT ar" 0 0 0 0 0 DATE: 7July 1987 MODEL: T136 Trencher {S/N 11999 & Below) SUBJECT: Coolant Recovery System The T135 and T136 (12000 and up) trenchers now use a coolant recovery system with the engine A kit, 6577144, is available for installation on previously built T136 trenchers, (S/N 11999 & Below) if desired The kit is offered as a customer option and can be ordered from Melroe Parts in Chicago The above is provided as product improvement information only No warranty is allowed DIRECT TO: ar" BOBCAT ar" 0 0 0 0 0 DATE: 	29 July 1987 MODEL: 	T906, Serial Numbers 0101 Through 0125 T907, Serial Numbers 1426 Through 2397 T909, Serial Numbers 2037 Through 3987 T911, Serial Numbers 1001 Through 1109 SUBJECT: 	Control Linkage The control linkage for the boom and dipperstick lever functions has been changed to provide longer service life Connecting link, 6529533, is replaced by: (Figure 1) REF PART NUMBER DESCRIPTION QTY 1 6592808 Link 2 2 6592809 Link 2 3 6592812 Pin 4 4 1F-208 PIN, cotter 4 Change only the boom and dipperstick lever functions Link, 6529533, is still used on the two stabilizer valve control functions Connecting links, 6592808 and 6592809, and pins are recommended as service parts replacement for earlier production Backhoes which have had failure of link, 6529533 (Machine serial numbers listed above) Melroe will give warranty compensation for parts and labor for machines which have had failure of the link, 6529533, as prescribed in the current Warranty Policy and Procedure Manual Order parts, as required for your area, from Melroe Parts in Chicago 0 0 I I ' '  ' , ' / ,  , 7 @'---J --· --c::qJ !ii' ; I , I I Old e [-" :1-' n---I I , -, link  e::--  JI , ,/ / ) (Still used for stabilizing) New: I / / / links : / / l  ---­ , / , ( , , I , , --- I I I ----J &'-jj ('// 0-1694 Figure 1 -2­ '· DIRECT TO: lY BOBCAT lY 0 D 0 - -- o --'-'--'-'----­ FIELD MODIFICATION 0 DATE: 7 August 1987 MODEL: 	741 (Serial numbers 20493 through 20527) 742 (Serial numbers 21264 through 21309) 743 (Serial numbers 32230 through 32964) 743DS (Serial numbers 51294 through 51305) 843 (Serial numbers 25273 through 26222) 1600 (Serial numbers 11338 through 11342) 2000 (Serial numbers 13376 through 13392) SUBJECT: 	Anti-cavitation Valves (6599160) --- ----· ·-··-----­ Anti-cavitation valves were installed in some loaders which can cause restriction to hydraulic flow The following symptoms may he caused by the defective anti-cavitation valves: Transmission warning light comes on momentarily while lifting, tilting and driving at the same time The 843 may have erratic bucket operatioA Melroe Company is sending new anti-cavitation valves to replace the defective valves Anti-cavitation valve location is shown in figure 1 ' Figure 1 Printed in U! ,- Accoding to our ecords, the following od?,11AlnL serial numberedn,/ , ­machines were shipped to your dealership: 7¥;!-?'N21Z2& V-ctl/'7Y--/1//C'/e?/JI/?; S/JJ3'71'6 0aZ3;J6t// v 3£t/ltj (Ti J' 21/3 f!J&!fl6tya 03Z 7'*vIJ Two anti-cavitation valves are used in the control valve They are located in the lift and tilt sections Please replace both valves, on affected machines Melroe will give compensation for cost of parts and one ( 1) hour labor for replacement One ( 1) additional hour is allowed for travel time for retailed machines Hold the defective valves for return authorization ----·-­ / ;,;!  \ t 2-Printed In USA DIRECT TO: BOBCAT ar"  ar" ar" D D D D DATE: 17 September 1987 MODEL: 100 Excavator SUBJECT: Correction to Technical Service Guide (6570583) Please make the following write-in corrections on page number six of the Technical Service guide, part number 6570583 Change part number for air cleaner element from 6640932 to read 6640708 Change part number for oil filter element from 6640932 to read 6640709 DIRECT TO: ar"' BOBCAT ar"' D D D D FIELD MODIFICATION o DATE: 18 September 1987 MODEL: 843, S/N 26001 Through 26327 SUBJECT: Servo Control Levers Servo control levers, 6577146 and 6577177, must be replaced by new parts on the serial numbered Model 843 loaders listed above Ref Part Number Description Oty ( 1 6577177 Lever, RH (without pin) 1 2 6577146 Lever, LH (without pin) 1 3 17C-1048 Bolt 2 4 6584863 Washer 2 5 850-10 Nut 2 I , I / I , I ,' I , I ( I --, I I I 1 : I :i 1--- --------::::::::::::--------, i : l u I I I w---o /T I 3 : : ,,,': ,'' l : : I  / ' , C I' 1 I 3-'f? :, § C) / 1-::;t-I l/1V : // ::: : J:-!-!  ,/ 'f> / I ,da1 I , " 1 ,,"' I : I I I I ,/ e "-----ft I I 2 l I I / -----I I 4 ! ,;;// --4---J) i/  5- 5-e E-1804 / Figure 1 '-/ According to our records, the following serial number machines(s) was/were shipped to your dealership: c260c:2608'? '270184 '2626Z o170/d?6di3;d?M9¥ v076318 Mel roe Cmpany'is sending replacement servo control levers, bolts, washers, and nuts for installation on these machines The parts will be billed to the dealerships Please replace the old lever (6577146 and 6577177), bolts ( 17C-612), and washers (6563914) with new parts Install the new parts as shown in figure 1 and tighten the nuts to 100-110 ft-lbs (135-149 Nm) torque Refer to Service Manual for neutral adjustment, if necessary Upon receipt of a properly completed warranty claim report, Melroe will give compensation for the cost of the parts plus two (2) hours labor for installation One ( 1) additional hour is allowed for travel time for retailed machines DIRECT TO: BOBCAT rn-"  rn-" rn-" 0 0 0 0 DATE: 24 September 1987 MODEL: 6428 SUBJECT: Anti-Dieseling Kit for Engine A kit is now available which, when installed, will prevent the engine from dieseling (run-on) after the ignition is turned off The kit is offered as a customer option and can be installed on any model 6428 engine Approximately three (3) hours labor are required to complete the installation Order the kit, 6577928, from Melroe Parts Sales in Chicago, IL Printed in USA DIRECT TO: C!r' BOBCAT C!r' D  D D 0 FIELD MODIFICATIONo DATE: 25 September 1987 MODEL: 843, S/N 26379 Through 26566 SUBJECT: Shields for Rear Axle Gussets Debris shields must be installed in the rear axle gusset areas to prevent debris from entering the cooling system The shields are required on all 26000 eries 843 loaders which have the new formed style motor cover installed   Part number 676557 According to our records, the following serial number Model 843 loader(s) was/were delivered to your dealership:----------­ o?639¢J6t/c2 Qt,(/7£ '2Gl/I/ These machines need to have the rear shields installed Melroe Company is sending shields (6577810), screws (84G-3712), and moulding (6577811) to dealerships for installation on affected machines Dealers will be billed for the cost of the parts Compensation will be given, for the cost of te parts and two hours labor for installation One ( 1 ) additional hour is allowed for travel time for retailed machines To 	install the rear shields: 1 	Lift and support the loader and remove the wheel assemblies (See Service Manual for procedure) 2 	 Remove ,thd motor covers 3 	 Mark and drill a size 13/32" hole at location shown (Fig 1 ) , I ;· A:, i f I Front Of Bobcat Fig 1 4 	Install the shields and fasten with the thread forming screws The shield for the left rear axle installs with the bent edge facing toward the axle (Fig 2, Item 1 ) The shield for the right rear axle has the bent I edge facing away from the axle (Fig 2, Item 2) -r­ r   :; ; s: Tighten the screws to 16-20 ft-lbs (22-27 Nm) torque '6 	Re-install motor cover and wheel assemblies Fig 2 r  , DIRECT TO: BOBCAT ar"  ar" ar" D D D D DATE: 21 October 1987 MODEL: T135 SUBJECT: Anti-Dieseling Kit for Engine A kit is now available which, when installed, will prevent the engine from dieseling (run-on) after the ignition is turned off The kit is offered as a customer option and can be installed on any model T135 engine Approximately three (3) hours labor are required to complete the installation Order the kit, 6577928, from Melroe Parts Sales in Chicago, IL Printed in USA DIRECT TO: CB"" BOBCAT CB"" CB"" 0 0 D 0 DATE: 17 November 1987 MODEL: T116 Trencher SUBJECT: Air Cleaner Service The T116 Trencher air cleaner is made up of a paper element and an outer foam pre-cleaner The outer foam pre-cleaner needs to be checked and cleaned every 1 O hours or sooner in severe dusty conditions The 	procedure for servicing the air cleaner is: 1 	Remove wing nut and top cover 2 	 Clean any loose dust from inside the base before removing the foam pre-cleaner 3 	 Remove the foam pre-cleaner and wash it in water and detergent Remove excess water by squeezing foam Allow to dry Distribute one tablespoon of SAE 30 engine oil evenly around the pre-cleaner Knead the pre-cleaner and wring out excess oil Change the paper element when it has become dirty Be sure top cover is in contact with top of element before tightening nut The 	above is provided as technical information only 1 Wash DIRECT TO: []"" BOBCAT []"" []"" D D D D DATE: 30 November 1987 MODEL: T114 and T116 SUBJECT: Latch For Backfill Blade Lever An improved latch for holding the backfill blade lever is included with the current Backfill Blade attachment The latch helps insure that the lever will not release the Backfill Blade during digging operation The improved latch can be installed on the T114 and early T116 Trenchers Parts required are: Part Number Description Oty 6577277 Mount 1 84G-3710 Screw 2 The parts can be ordered from Melroe Parts in Chicago The above is provided as product improvement information only Printed in USA /WELROEco11PANT ,  GENERAL · bobcat SERVICE BULLETIN AFFECTING: Product CONSTRUCTION & INDUSTRIAL BUCKETS Model 54" AND 60" Serial No                          Manual No ROUTE TO ATTENTION  D  0  0 D SUBJECT: BOB-TACH MOUNTING SLOTS The locking wedges on the Bob-Tach are closer together for the following loaders: M444 M700 M 500 720 M600 721 M61 0 722 The Construction & Industrial bucket is the only attachment that needs modification as follows : Measure and mark the location for two additional slots in the lower Bob-Tach mounting frame The bottom edge of the new slots must be even with the bottom of the existing slots Cut two new slots Remove the two gussets from the upper mounting frame This will allow the older Bob-Tach to engage the mounting flange of the bucket (2) Gussets MC-1060 Printed in USA DIRECT TO: ar" BOBCAT ar" ar" D D D D DATE: 3 December 1987 MODEL: 740 and 843 Series SUBJECT: Gearbox Seal Tool (MEL-1047) The tool for installing the reduction gearbox oil seal has been revised to improve seal installation and prevent damage to the seal Tools shipped from OTC after January 1, 1988, will be of latest design Existing tool can be reworked to the new dimensions, if desired This process is easily done in a turning lathe New dimensions are shown below  only DIRECT TO: []!"" BOBCAT []!"" []!"" D D D D DATE: 10 December 1987 MODEL: T108 and T116 SUBJECT: Telescoping Boom After 1 December 1987, the Trencher Models listed above will have an adjustable boom as standard equipment The 	new boom has the following features: 1 	 Adjustable for 24" through 36" digging depths 2 	 Separate bleed-off fitting for grease cylinder to release chain tension 3 	 No cushion spring 4 	 End roller instead of sprocket 5 	 New boom can be installed on older T108, T114 and T116 Trenchers (old boom will not fit on new machines) 6 	 New boom holder Adjustment is made by repositioning or removing the spacer on the boom end The machines will be shipped with boom installed and set for 30" digging depth Updated Operator's Manual describes the procedure for changing the boom length and setting digging chain tension The above is provided as product update information only BOBCAT DIRECT TO: CB' CB' rn' D D FIELD MODIFICATION D D DATE: 14 December 1987 MODEL: T116 Trenchers (Serial Numbers 11001through11318) SUBJECT: Ignition Switch Due to the short service life of the ignition switch, 6519592, a new switch, 6648503, must be installed Replacement switches, part number 6648503, are being shipped to those dealerships which have affected machines in their territory According to our records, the following serial number model T116 Trencher(s) was/were shipped to your dealership:         Please replace the ignition switch, part number 6519592, with switch, 6648503 on this/these machines(s) The switch must be installed so that the small drain hole is toward the rear of the machine The key is included with the switch Dealerships will be billed for the cost of the parts Melroe will give compensation for one-half ( 1 /2) hour labor to install the new switch One ( 1) additional hour is allowed for travel time for retailed machines DIRECT TO: 0 CB' BOBCAT CB' 0 0 0 0 0 DATE: 14 January 1986 MODEL: 943 SUBJECT: Proper Use Of Cap For Hydraulic Filter Housing Hydraulic Filter Caps, Part Number MEL-1277, are available for use when replacing the drive belt The caps can be ordered from Service Tools, Owattona, MN It is recommended that the hydraulic filter elements be removed first to allow more working room when replacing the drive belt Using the two caps to cover the filter heads will prevent oil drip into the engine compartment (Figure 1) BE SURE TO REMOVE THE FILTER CAPS AND REINSTALL THE ELEMENTS BEFORE RUNNING THE ENGINE Running the engine with the filter caps still installed would allow unfiltered oil to enter the ydrostatic system through the bypass valve This could result in pump 1ailure The above is pT vided as technical information only Printed in USA DIRECT TO: [13"' BOBCAT [13"' [13"' 0 0 0 0 DATE: 15 January 1986 MODEL: 905-B Backhoe SUBJECT: Operating RPM on Model 530 and 540 Series Loaders The model 905-A and 905-8 backhoe requires about 6 gallons per minute hydraulic oil flow for best operating performance Exceeding 6 gallons per minute will cause too fast swing and digging action and could result in swing chain breakage and accelerated wear of parts Since the 530 and 540 series Bobcat hydraulic flow is 8 to 85 gallons per minute it is necessary that engines on these models be run at no more than 2200 RPM to reduce the oil flow to the backhoe Operator manuals will be revised to include this information  only Printed i:  DIRECT TO: rn-" BOBCAT C1r" 0 0 0 0 0 DATE: 	20 January 1986 MODEL: 	630, 640 Series SUBJECT: 	Reinforcing Disc For Chaincase (6568413) A steel disc is available for reinforcing the chaincase where the hydrostatic motor is mounted The disc can be welded onto the inside of the chaincase on machines which show signs of stress cracks at the mounting bolt holes These stress cracks may occur if the machine has been subjected to severe load conditions To install the discs: 1 	 Drain the chaincase fluid and remove the motors and drive chains 2 	 Position the disc inside the chaincase and align the 4 mounting holes 3 	 Weld as shown in figure 1, 90 degrees in front and rear of the plate and around the inside diameter TOP (l ; 90° 	141  Printed in USA DIRECT TO: CB"' BOBCAT CB"' D D D D D DATE: 4 February 1986 MODEL: 	440, 540, 640, 740 (Series) 843, 1213, 1600, 2000, RTF SUBJECT: 	Backup Seal for Relief Valves (Melroe Valve) The split backup seal, 5205224, for port relief and anti-cavitation valves has been replaced by non-split seal, 73K-14 The new seal is less likely to get pinched when installing the valve in the port ;OQQ-0·Cl1II}Jo I ' Back-Up iy-O - Seal ! f r--o-Q-aQ) Back-Up I I I Seal 1 I I I I I : f : r-----0·1'-Q-c J) 'I I ''I I \ 	t ()J:>-Q·OO, / f:: I I 1 I I f ; ! / Back-Up :   : : : : Seal -P-· J:: p,Ji -:, --r- J : - '!I r -­ -'lt--:::::l) , ,:i[j   J j E-1509 Figure 1 	Figure 2 Dealers are advised to order a number of the new seals for their stock Use them when servicing the port relief or anti-cavitation valves (Fig 1), instead of using the split seal which comes in the seal kit Two styles of seals may be used One style has contour for th 0-ring and must be installed as shown in illustration above The other style has no contour and can be installed either way Seal kits will be revised to include the improved seal The above is provi as technical information only Printed in USA DIRECT TO: CW BOBCAT CW D D D D D DATE: 6 March 1986 MODEL: 943 (All); 974 (S/N 12954, 12956 & Above) SUBJECT: Engine Balancer (Midmounted) Some failures of the engine center-mounted balancer assembly have been reported Investigation reveals that the failure may occur in three areas: 1 The drive idler gear comes loose 2 Balance gear teeth are soft 3 The balance gears were not correctly timed If a sudden loss in oil pressure occurs during operation, stop the engine immediately Disassemble the engine and check for balancer failure Also check the oil pump relief valve spring for damage Inspect the connecting rod and main bearings for damage before reassembling If damage is found, contact Melroe Service Department for further instructions DIRECT TO: BOBCAT [13"'  D D D D D D DATE: 7 March 1986 MODEL: 443, 543, 643, 743, 1600 SUBJECT: Torque For lnjction Pump Delivery Valve Holder The delivery valve holder torque must be maintained or fuel may leak past the seat and into the engine crankcase thereby diluting the lubricating oil The diluted crankcase oil could result in increased wear of engine parts Therefore, it is important that the delivery valves are checked for correct torque, especially whenever the injection lines have been removed for any reason The correct torque for the delivery valve holder is 25 -36 ft-lbs (34 ­49 Nm)  only ; ;Printed in USA DIRECT TO: BOBCAT CB"'  CB"' CB"' D D D D DATE: 10 March 1986 MODEL: 540 Thru 943 SUBJECT: Adhesive For Operator Cab Insulation A new adhesive is now used for securing the insulation in the cabs on present production Bobcat loaders This adhesive has excellent bonding qualities and is also recommended for re-securing any insulation which may have come loose on loaders in the field The new adhesive is called 3M 74, foam adhesive, and comes in a 19 1/2 ounce spray can The product may be obtained from any 3M (Minnesota Mining & Manufacturing) distributor Check the telephone yellow pages for local listing, under "Adhesives" The product will also be available at a later date from Melroe Parts Marketing at Chicago Part number is 6632469 The above is provided as parts information only Printed in USA DIRECT TO: CB" BOBCAT CB" D D D D D DATE: 18 March 1986 MODEL: 1600, 2000, RTF SUBJECT: Water in Brake Assembly (SyTec) When brake assembly (6585588) is being installed on the drive motor, be sure that the gasket is positioned correctly before installing the end plate If the gasket is installed the wrong way (figure 1), water can enter the housing and result in seizure of the brake discs, especially during freezing temperatures If the brake will not release after the engine has started and servo pressure is normal, the cause may be because water is in the brake housing and has either frozen or rusted the discs together The unit must then be disassembled, cleaned and e-assembled, insuring that the gasket is correctly installed Also, be sure that the threads on the lare nut are coated with an anti-vibration compound to prevent the nut from turning and disengaging the brake spline  only Printed in USA DIRECT TO: rn""' BOBCAT rn""' D D D D D DATE: 19 March 1986 MODEL: 540 Thru 843 (S/N 20001 & Above), 943 SUBJECT: Rear Window Installation The rear window kit, 6568709, has been revised to include an improved latching design which replaces the slot and "T" bar formerly used The new latch uses a stud, bracket, and two threaded knobs (Figure 1) The new parts can be used to replace the "T" bar assembly, if desired The new parts can be ordered from Melroe Parts Marketing, Chicago Parts are: Bracket -6571532 (1) Mount -6571533 (1) Knob -6571529 (2) 0-Ring -58K-109 (2) -1-Printed in USA When installing the window, carefully follow the instructions to avoid breaking the glass Be sure to install the mounting bracket and stud bracket so that the window aligns perfectly with the threaded stud (Figure 2) B-9656 B-9631 Figure 2 When installing the window in the bottom hinge be sure that the "offset" (Item 1) is toward the cab and that the rounded pivot is inside the slotted rail (Figure 3) Figure 3 Warranty compensation will not be approved for window breakage resulting from failure to follow instructions when installing the window only -2­ DIRECT TO: CB"' BOBCAT CB"' D D D D D DATE: 4 April 1986 MODEL: 825 SUBJECT: Installing Cessna Remanufactured Components Occasionally a warranty claim is received for a remanufactured hydrostatic pump or motor which has failed after operating only a short period of time Inspection of the failed component often reveals that the cause of failure was due to contaminated fluid in the system This was particularily more prevalent in circumstances where the failed component had been installed by the Bobcat owner The importance of observing absolute cleanliness when repamng hydrostatic transmission systems cannot be over emphasized Non-dealer service personnel may not be aware of the required procedure to be followed when repairing a hydrostatic transmission system Parts must be clean and protected from contamination When a component has failed, the related componentry must also be disassembled, inspected for damage and repaired as necessary The tube lines and hoses need to be drained and washed with clean solvent The fluid filters must be replaced, new o-rings and gaskets installed during reassembly Torque requirements must be followed when tightening bolts All components must be filled with fluid prior to initial startup System checks must be made (charge pressure, relief pressure, etc) to determine performance prior to returning the machine to work Customers must be made aware of the above requirements when they insist on doing their own repair work or having the repairs made by non­Bobcat dealership service agencies Printed in USA BOBCAT FIELD MODIFICATION DATE: 	10 April 1986 MODEL: 	Farmboy -S/N 13001-13164; 440 -S/N 11001-11711; 443 -S/N 11001-12030 SUBJECT: 	Bolts For Drive Control Linkage DIRECT TO: CB" CB" D D D D D The bolts which hold the linkage bars to the pintle levers and steering control shaft must be 1-3/4" long (Figure 1) Figure 1 The serial number machines listed above must be inspected for the correct bolts If 2 to 3 threads are visible beyond the nut, the bolt is correct If the threads barely reach the end of the nut the bolts must be replaced Melroe will give compensation for one (1} hour labor to replace bolts One additional hour is allowed for travel time for retailed machines Printed in USA DIRECT TO: BOBCAT CB"  CB" CB" D D D D DATE: 	5 May 1986 MODEL: 	1600 -S/N 11001 Thru 11241; 2000 -S/N 13092 Thru 13201; RTF -S/N 15021 Thru 15026 SUBJECT: 	Seat Bars Changes have been made on production machines to improve the seat bar action A detent with heavier springs is now used to prevent the seat bars from falling from the raised position Oilite bearings are also installed The heavier springs (P/N 6584584), can be installed on earlier built machines (Serial Numbers Above) (Figure 1, Item 28)  only Figure 1 (ljt,,     r------­ 28 L  CJl--(l I 	-------I IJ---(j 	-­ ---n--(j I I r'--fl I I I I 	o--(jj-----/ --- I I 	\J -------1' i Printed in USA DIRECT TO: CB" BOBCAT CB" D D D D D DATE: 9 May 1986 MODEL: 943, 974 (Engine S/N LD-----U055422 & Below) SUBJECT: Engine Balancer (Midmounted) NOTE: 	This service letter replaces service letter, same subject, dated 6 March 1986 Some failures of the engine center-mounted balancer assembly have been reported Investigation reveals that the failure may occur in three areas: 1 The 	drive idler gear comes loose 2 Balance gear teeth are soft 3 The 	balance gears were not correctly timed If a sudden loss in oil pressure occurs during operation, stop the engine immediately Disassemble the engine and check for balancer failure Also check the oil pump relief valve spring, for damage Inspect the connecting rod and main bearings for damage before reassembling If damage is found, contact Melroe Service Department for further instructions Printed in USA DIRECT TO: BOBCAT CB'  CB' 0 0 0 0 0 DATE: 13 May 1986 MODEL: All Current Models SUBJECT: Engine Vibration Dampers (6514897, 6561557 & 6560633) When installing the neoprene rubber vibration dampers for the engine mounts it is important that they are not coated with oil The dampers must not be dipped in oil to make them easier to install as this practice will shorten their service life Soap should not be used either The manufacturer recommends that water be used instead only Printed in USA DIRECT TO: CM" BOBCAT CM" CM" D D D D DATE: 14 May 1986 MODEL: All SUBJECT: 12 Month Service Interval Scheduled service intervals for 250 hr, 500 hr and 1000 hr items are revised to read "or every 12 months" This change to the service schedule is necessary to insure that minimum required services are performed on machines which do not accumulate many operating hours over a long period of time Service schedules are being updated in forthcoming Operator's and Service Manuals Printed in USA DIRECT TO: BOBCAT IB"  IB" D D D D D DATE: 13 May 1986 MODEL: All Current Models SUBJECT: Engine Vibration Dampers (6514897, 6561557 & 6560633) When installing the neoprene rubber vibration dampers for the engine mounts it is important that they are not coated with oil The dampers must not be dipped in oil to make them easier to install as this practice will shorten their service life Soap should not be used either The manufacturer recommends that water be used instead only Printed in USA DIRECT TO: (11" BOBCAT (11" 0  D 0 0 0 DATE: 17 June 1986 MODEL: 943 SUBJECT: Engine Crankcase Dipstick & Tube The engine must have the correct dipstick tube and dipstick installed to give a correct reading of the crankcase oil level The dipstick must match the tube Two sizes are in use The correct dipstick tubes and matching dipsticks are as shown below: MAX \----2381 MAX \----1334­ DIPSTICK P/N 6632539 Eng S/N 022653M & Below DIPSTICK TUBE P/N 6515731 OVERALL LENGTH: 2150" Eng S/N 022653M & Below DIPSTICK P/N 6633915 Eng S/N 022654M & Above r- LENGTH, 1050" DIPSTICK TUBE P/N 6510524 Eng S/N 022654M & Above Figure 1 Figure 2 If a new dipstick is being ordered, be sure that it matches the tube in the engine, per the dimensions shown in figures 1 & 2 above The foregoing is provided as technical information only No warranty is implied DIRECT TO: CW BOBCAT CW CW  D D D D DATE: 23 July 1986 MODEL: 6428 SUBJECT: Heater Connections Hose A short section of hose is installed at the connections for heater hoses located at the forward end of the engine This hose is cut short and intentionally "kinked" to block and prevent coolant from bypassing (Figure 1) Figure 1 Dealers are cautioned not to remove the kinked hose except to install heater hoses and heater kit Please advise your customers of the forgoing DIRECT TO: CB"' BOBCAT CB"' 0 0 0 0 0 DATE: 25 July 1986 MODEL: 640, 740 Series SUBJECT: Pump Mounts A new stronger front pump mount is being installed on present production 640 and 740 series loaders The new pump mount (6569553) replaces formerly used mount (6557463) and can be used on earlier production loaders as a service replacement part The rear pump mount has been revised to provide better support and improved coupler alignment The part number (6562697) is not changed for the rear mount REAR FRONT Old Old New E-1492 The above is provided as product improvement information only No warranty is implied Printed in USA DIRECT TO: CB' BOBCAT CB"' D II 0 D 0 DATE: 7 August 1986 MODEL: 740 Series 843 SUBJECT: Drive Chains & Connector Links Drive chains, under the brand name "Daido", are sometimes installed in 740 series and 843 production Bobcat loaders The "Daido" chains use the diamond brand connector link, part number 6510614 (843) or 6510171 (740's), as a service part The next issue of the parts fiche will reflect this information The above is provided as parts information only DIRECT TO: [il"' · BOBCAT flf"" 1--1 Servicele-tter I I : ' I ' ' :'> : ' () -· ,:,\ I I ----, qFu1vrn <?, r] -: SE r 1986 ­ )­ L-1  ":::' ''­  /:\> ·\ T\\ DATE: 	8 August 1986 MODEL: 	Trenching Attachment (With 3/8" Bolt Split Sprocket) Used on Melroe Trencher Model T-136 & Midmark Workmate SUBJECT: ; Sprocket Bolt Failure The 3/8" bolts, which hold the split sprocket on the trenching unit, may shear off if trenching in rocky terrain To remedy this problem install 1/2" bolts to hold the sprocket (Bolt, part number 17C-840 and Nut, part number 850-8) Additional holes must be drilled in the sprocket halves and mounting hub The existing holes must aiso be drilled larger to accommodate the 1/2" bolts Drilling should be done in a machine shop Figure 1 	Figure 2 -1-	Printed in US A DIRECT TO: [B"' BOBCAT rB"" n  0 \ 0 ------­0 D DATE: 22 August 1986 MODEL: 540, 640, 740 Series & 843 SUBJECT: Chaincase Breather Presently built loaders have a larger chaincase breather, and a baffle below the breather (under the chaincase cover) to prevent oil from leaking out during loader operation The new breather can be installed on earlier built loaders  J Parts required are: (Order from Melroe Parts Sales) 6632601 Filter Breather 6575654 Cover Assembly only 9 6632601 I Printed in USA DIRECT TO: CB"' BOBCAT CB"' D D D D D DATE: 15 September 1986 MODEL: 540, 640, 740 SUBJECT: Centering Control Linkage The centering control mechanism has been revised on present production Bobcats listed above The centering link, bushing, screw, and spring is replaced by an improved design system The following parts are affected: MODEL# FORMER P/N DESC REPLACED BY P/N QTY , 640, 740 6562767 Link 6571899 1 540, 640, 6505082 Spring 6572026 1 740 540, 640, 6558429 Bushing 6571988 1 740 540, 640, None Guide 6571991 2 740 The improved parts can be installed on earlier built loaders providing that all of the new parts affecting the loader are used The above is provided as product improvement information only No warranty is implied Prin DIRECT TO: ur" BOBCAT ur" ur" D D D D DATE: 23 September 1986 MODEL: 640 Series SUBJECT: Wheel Nut Tightening Problem An interference may exist between the wheel nut and the lip in the wheel rim This condition can cause improper bearing area for the nut chamfer and result in loose nuts and eventual rim damage To correct this condition, use a one inch, 90 degree chamfering tool in the wheel lug holes to cut away any lip interference If a chamfering tool in unavailable, use a grinder to remove the lip interference (Figure 1 ) C-2904 The above if offered as technical information only DIRECT TO: BOBCAT CB"  CB" 0 0 0 FIELD MODIFICATION 0 0 DATE: 7 October 1986 MODEL: T-136 (Trencher) -S/N 11001 through 11110 SUBJECT: Wheel Rims Some wheel rims installed on machines listed above may not fit flush against the axle hub, due to small hole size for the lug bolts A visual inspection must be made of each wheel to see if the rim is correctly mounted Please inspect each wheel The rim must be flush against the hub If a gap exists, remove the wheel Use a 90 degree chamfering tool and cut a new diameter to 7/8", outside diameter Use a size 21 /32" bit to drill out the mounting holes to the correct size Remove the stud and install washer (P/N 6641183) between the stud head and the hub flange Melroe will give compensation for 1/2 hour labor for each wheel which needs to be corrected One additional hour is allowed for travel time for retailed machines Printed in US A DIRECT TO: BOBCAT CB" CB"  D D D FIELD MODIFICATION D D DATE: 14 October 1986 MODEL: 843 SUBJECT: Steering Centering Control Linkage Present production model 843 Bobcats, starting at serial number 22882, have ·centering control linkage with a 1 /2" diameter bolt and an improved design spring The centering control system has been improved Kit, part number 6576281, is available through Melroe Parts Marketing for conversion of 843 model Bobcats with linkage problems caused by spring and bolt failure The conversion kit may be installed on all 843 model Bobcats between serial numbers 16192 and 22881 Warranty compensation will be given only for machines that are still within the normal six month warranty period  of kit cost and two (2) hours labor with an additional one ( 1) hour travel time for retail units /--Bolt Bushing p n   V· Spring )"' H!' \/ #'       , ·---Nut Bracket---/ DIRECT TO: CB""' BOBCAT CB""' 0 0 0 0 0 DATE: 	14 November 1986 MODEL: 	Serial Numbers & Above As Follows; 741-20335, 742-20959, 743-28147, 7430$-51207, 843-22730, 1213-11062 SUBJECT: 	Plastic Chain Guide Plastic chain guides are now used in the chain cases of present production model and serial number Bobcats listed above The new guides help eliminate chain noise The guides can be installed in older machines, if desired, at owners expense Parts required are as follows: 6569808 Guide 2 6569807 Bushing 2 17C-1252 Bolt 2  only Printed in USA DIRECT TO: BOBCAT Dr"  Dr" Dr" 0 0 0 D DATE: 19 November 1986 MODEL: T-136 Trencher SUBJECT: Engine Overheating Incorrect digging operation can place an excessive load on the trencher and result in engine overheating To obtain best results when operating the trencher digging attachment, use the following procedure: 1 	 Set the throttle at full engine RPM (2800) 2 	 Set the chain drive lever at approximately 3/4 position 3 	 Operate the traction drive slow enough to keep the engine RPM above 2500 Avoid overloading the engine Drive speed will vary, depending upon digging (ground) conditions which must be given prime consideration whenever operating the trencher digging attachment Proper observance of the foregoing will insure best performance and maximum service life of the trencher DATE: MODEL: SUBJECT: BOBCAT 3 January 1985 443, 543, 643, 743 (Kubota Engine) Crankshaft & Cylinder Head (Service Parts) DIRECT TO: []!""" rn' 0 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision NOTE: 	This Service Letter replaces Service Letter, same subject, dated 29 December 1983 The replacement crankshaft and cylinder head is shipped with screws and plugs not installed The screws or plugs are in a plastic bag which is included in th·e carton with the main part The screws or plugs MUST BE INSTALLED before assembling the engine (Figures 1 & 2) Failure to install these parts could result in SERIOUS DAMAGE to the engine due to loss of oil pressure Parts warranty compensation will not be given for failures resulting from not installing the screws or plugs LCD ' / ', / 	' / 	', Plugs (39740351 6> " Screws (6598116) 'q, Figure 1 Figure 2 *NOTE: The crankshaft plugs must be securely staked to prevent them from coming out during engine operation Printed in USA DIRECT TO: D 	 BOBCAT r-­ D 	 ( D D D FIELD MODIFICATION D D DATE: 7 January 1985 	Additional information about this subject is found in the following: MODEL: 440, 443 Service Bulletin        BTI Bulletin         SUBJECT: Axle Bearing Lubrication Installation Inst Manual Revision The axle bearings on recently built 440 series Bobcats did not receive initial  lubrication during assembly, therefore, the following lubrication procedure ( must be done to in-stock and retailed machines According to our records the following serial number machine(s) were shipped to your dealership: Please insure the complete lubrication of the wheel bearings by doing as follows: 1 	 Raise the lift arm and install a lift arm stop 2 	 Raise the front of the loader until the wheels are at least 6" off the floor 3 	 Remove the check/fill plug and add three gallons of Clark hydraulic fluid (P/N 6563328) to the chaincase Install the plug 4 	 Lower the loader so that front and rear axle tubes will fill with fluid Operate machine for a few minutes 5 	 Place a clean container under the chaincase check/fill plug Remove the plug and drain fluid down to check plug level Melroe Company wil give compensation for 3 gallons of hydraulic fluid and one hour labor to complete the lubrication process One additional hour is allowed for travel time for retailed units Printed in II a DIRECT TO: rn"" BOBCAT D D D D D D DATE: 11 January 1985 	Additional information about this subject is found in the following: MODEL: 640, 740 Series Service Bulletin        BTI Bulletin 	          SUBJECT: Installing Vane Pump Coupling Installation Inst Manual Revision (Vickers) When installing the vane pump coupler on the hydrostatic pump assembly, use the following procedure: 1 	 Turn the threaded end of the vane pump shaft into the pump drive shaft until the shaft bottoms out, then turn the shaft counterclockwise 1/4 turn to align the splines (approx 020" ) 2 Install the coupling over the splines and install the 	snap ring 3 	 Install the vane pump and secure with the two screws Tighten the screws to 25 -28 ft-lbs (34 -38 Nm) torque Important: 	Vane pump failures may occur if the above procedure is not followed  only BOBCAT FIELD MODIFICATION DATE: 17 January 1985 MODEL: 975, 1080, 1080 B SUBJECT: Bracket for Injector Tube Lines DIRECT TO: rn-" rn-" rn-" 0 0 0 o Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The bracket (6598293) for holding the injector tubelines is replaced by an improved bracket (6593429) The bracket is installed as shown in Figure 1 Remove the inner half of the bracket (with threaded holes) and replace it with the revised bracket Mount the bracket on the exhaust manifold (Do not use the washers under the mounting screws) Figure 1 If you experience injector tube line failure on the John Deere engine, order the new bracket from Melroe Parts Marketing and install it  for replacement costs for installation of bracket where tube line failure is a problem Two hours labor is allowed for retailed machines Printed in USA DIRECT TO: IY BOBCAT IY D  D D D D DATE: 	14 November 1986 MODEL: 	Serial Numbers & Above As Follows; 741-20335, 742-20959, 743-28147, 743DS-51207, 843-22730, 1213-11062 SUBJECT: 	Plastic Chain Guide Plastic chain guides are now used in the chain cases of present production model and serial number Bobcats listed above The new guides help eliminate chain noise The guides can be installed in older machines, if desired, at owners expense Parts required are as follows: 6569808 Guide 2 6569807 Bushing 2 17C-1252 Bolt 2  only Printed in USA DIRECT TO: BOBCAT rn-'  CB""' rn-' D D D D DATE: 19 November 1986 MODEL: T-136 Trencher SUBJECT: Engine Overheating Incorrect digging operation can place an excessive load on the trencher and result in engine overheating To obtain best results when operating the trencher digging attachment, use the following procedure: 1 	 Set the throttle at full engine RPM (2800) 2 	 Set the chain drive lever at approximately 3/4 position 3 	 Operate the traction drive slow enough to keep the engine RPM above 2500 Avoid overloading the engine Drive speed will vary, depending upon digging (ground) conditions which must be given prime consideration whenever operating the trencher digging attachment Proper observance of the foregoing will insure best performance and maximum service life of the trencher DIRECT TO: []"" BOBCAT []"" D  D D D D DATE: 3 January 1985 	Additional information about this subject is found in the following: MODEL: 443, 543, 643, 743 (Kubota Engine) Service Bulletin        BTI Bulletin         SUBJECT: Crankshaft & Cylinder Head (Service Installation Inst Parts) Manual Revision NOTE: 	This Service Letter replaces Service Letter, same subject, dated 29 December 1983 The replacement crankshaft and cylinder head is shipped with screws and plugs not installed The screws or plugs are in a plastic bag which is included in th·e carton with the main part The screws or plugs MUST BE INSTALLED before assembling the engine (Figures 1 & 2) Failure to install these parts could result in SERIOUS DAMAGE to the engine due to loss of oil pressure Parts warranty compensation will not be given for failures resulting from not installing the screws or plugs / / Figure 1 	Figure 2 *NOTE: The crankshaft plugs must be securely staked to prevent them from coming out during engine operation Printed in USA ,,,- DATE: BOBCAT FIELD MODIFICATION 7 January 1985 MODEL: 440, 443 SUBJECT: Axle Bearing Lubrication DIRECT TO: 0 0 0 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin         BTI Bulletin          Installation Inst Manual Revision The axle bearings on recently built 440 series Bobcats did not receive initial lubrication during assembly, therefore, the following lubrication procedure must be done to in-stock and retailed machines According to our records the following serial number machine(s) were shipped to your dealership: Please insure the complete lubrication of the wheel bearings by doing as follows: 1 	 Raise the lift arm and install a lift arm stop 2 	 Raise the front of the loader until the wheels are at least 6" off the floor 3 	 Remove the check/fill plug and add three gallons of Clark hydraulic fluid (P/N 6563328) to the chaincase Install the plug 4 	 Lower the loader so that front and rear axle tubes will fill with fluid Operate machine for a few minutes 5 	 Place a clean container under the chaincase check/fill plug Remove the plug and drain fluid down to check plug level Melroe Company wil give compensation for 3 gallons of hydraulic fluid and one hour labor to complete the lubrication process One additional hour is allowed for travel time for retailed units PrintAti in 11 C: I\ DIRECT TO: rn""' BOBCAT rn""' D D D FIELD MODIFICATION D D DATE: 18 January 1985 	Additional information about this subject is found in the following: MODEL: 843 Service Bulletin        BTI Bulletin        SUBJECT: Motor Case Drain Orifice Installation Inst Manual Revision       The motor case drain orifice, P/N 6599654 has been re-installed on production 843 Bobcats beginning with machine serial number 20164 This orifice has been previously used but was removed on production 843 Bobcats beginning with machine serial number 15623 The orifice (Fig 1, Item 1) is installed at the motor case drain port block (Item 2) ,0 , , /S;-2 / \I',/ I / /' \ / r I o I 1-iil : I I I I I 'f' I I 'f' I I \tt I -1­ Printed in USA The orifice has been removed due to circuitry· changes and was no longer needed However, some of the 843 Bobcats built without the orifice (S/N's 15623 thru 20163) may experience noisy and erratic steering If any of the above listed serial number machines display these drive characteristics, check for an orifice in the case drain port block, and if no orifice is present, one should be installed The orifice, 6599654, can be ordered thru Melroe Parts Marketing Melroe Company will give compensation for the cost of the orifice and one hour labor to install One additional hour is allowed for travel time FIELD MODIFICATION D DATE: 15 February 1985 MODEL: 440, 443 SUBJECT: Belt Tensioner Springs (6564892) BOBCAT DIRECT TO: CB' CB' D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The belt tensioner springs installed on some model 440 and 443 loaders may fail after a short period of use Melroe is sending new springs to replace the existing springs on affected loaders According to our records, the following model and serial number machines were shipped to your dealership: The belt tensioner springs must be replaced on these machines Refer to the 440/443 Service Manual (6566694) for replacement procedure The engine should be removed to make the spring replacement Melroe Company will give compensation for the cost of the replacement springs and 5 hours labor to make the replacement One additional hour is allowed for travel time for retailed machines Printed in USA DIRECT TO: CB" BOBCAT 0 D 0 D D D DATE: 7 March 1986 MODEL: 443, 543, 643, 743, 1600 SUBJECT: Torque For Injection Pump Delivery Valve Holder The delivery valve holder torque must be maintained or fuel may leak past the seat and into the engine crankcase thereby diluting the lubricating oil The diluted crankcase oil could result in increased wear of engine parts Therefore, it is important that the delivery valves are checked for correct torque, especially whenever the injection lines have been removed for any reason The correct torque for the delivery valve holder is 25 -36 ft-lbs (34 ­49 Nm)  only Printed in USA BOBCAT 0 Service letter 0 0 0 Bobcat Speclallat 0 0 FIELD MODIFICATION o DATE: 20 March 1985 DIRECT TO: MODEL: 2000 SUBJECT: LOADER SERIAL NUMBER PLATE Serial number plates with the wrong loader prefix number were installed on some Model 2000 loaders These plates must be replaced with plates which have the correct prefix number on them (correct prefix is 5027-) New serial number plate(s) are being sent to District Managers Please arrange to have the serial number plate(s) replaced on affected machine(s) at once Contact the area District if additional assistance is needed Before installing the new plate, be sure to verify that the last five numbers on the new plate are the same as the last five numbers on the old plate If these numbers are not the same, please call Peggy Belling at Melroe Company, Service Department, (701) 678-6484 THE OLD SERIAL NUMBER PLATE MUST BE RETURNED TO MELROE COMPANY A partially completed warranty claim form is enclosed to give warranty compensation for labor and travel involved Be sure to return the old serial number plate with the completed warranty form Machine S/N Dealership Mailing: District s, District s ­ DATE: MODEL: SUBJECT: BOBCAT 24 April 1985 540, 640 Series New Wheel Bolts & Torque DIRECT TO: ar' ar' ar' D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision Present production Model 540 and 640 Series Bobcats now use 9/16" wheel bolts and nuts Bolt part number is 6559502; nut part number is 6519169 Wheel nut torque for machines with 9/16" bolts is 105 -115 ft-lbs (142 -156 Nm)  only, not a field modification IWELROECOJIO'ANT   ,    GENERAL ---SERVICE BULLETIN AFFECTING: Product BOBCAT LOADER Model ALL Serial No                        Manual No ROUTE TO ATTENTION  [3  [3  D D SUBJECT: STEEL CAPS & PLUGS FOR HYDRAULIC MAINTENANCE This Bulletin replaces General Service Bulletin #G-009 Dated 12 July 1984 Caps and plugs for use when testing or servicing the hydraulic/hydrostatic system are listed on the chart below The chart lists the sizes, part numbers and pertinent models for the caps and plugs These items may be ordered from Melroe Parts Marketing in Chicago CAP & PLUG CHART Additional information about this subject is found in the following: Service Letter BTI Bulletin         Installation Instr Manual Revision  Indicates which Models the plugs and caps are used on A  , UMT Of' -EQUIPMENT COMPAHY Printed in USA BOBCAT DIRECT TO: []""' []""' 0 0 0 0 FIELD MODIFICATION o DATE: MODEL: SUBJECT: 28 June 1985 Backhoe -907 S/N 1570 thru 1660 909 S/N 2249 thru 2489 911 S/N 436 thru 518 Control Valve Plug Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin           Installation Inst Manual Revision The plug, 6631050, installed in the inlet section and bucket section of the control valve may develop a leak at the 0-ring seal (Fig 1) If this condition occurs on a backhoe serial number listed above, order replacement plugs, part number 945193 from Melroe Parts, Chicago Three (3) plugs are needed for each backhoe Special tools are needed to remove the leaking plugs and install the new plugs Your District has the necessary tools If you experience a problem of leaking plugs, contact your District and he will arrange to have the tools delivered to you on a loan basis Figure 1 6631050     fl <fl6631050 I IG--am---- - b I I ) --11 G---·+-() 6631050----- ' E-1622 -1-Printed in USA To replace the plugs: 1 	 Use the large machined socket to remove the old plug 2 	 Screw the center poppet out of the new plug until it is even with the bottom of the plug 3 	 Use the special tool to install the plug (With 0 -ring) and tighten it fully 4 	 Screw the center poppet in until it stops Then use the small special socket to tighten it to 8 ft-lbs torque Figure 2 Melroe will give compensation for the cost of the parts plus two hours labor tor installation One additional hour is allowed for travel time for retailed units F -2­ 1 6631062 Tubeline (#1) 2 6631063 Tubeline (#2) \ 3 6631064 Tubeline (#3) 4 6631065 Tubeline (#4) Always use the improved tubeline when replacing tubelines POLICY: The above is provided as product improvement information only No Old Production warranty is allowed B-7345 Tubeline Tubeline Fig 1 Tubeline Identification AWARNING Keep away from fuel under pressure from injector nozzles It may be invisible Wear safety goggles Fuel under pressure can penetrate skin or eyes If fluid enters skin or eyes, get immediate medical attention Failure to obey warnings can cause injury or death W-2072-0284 Fig 2 Injector Tubeline Location Printed in USA A -SUNIT OF-EQUIPMENT COMPANY llfELROECOMPANY ------- bobcat SERVICE BULLETIN iiiiiiiiiiiiiii AFFECTING: Product BOBCAT LOADER 975 (John Deere) Model Serial No                        Manual No SUBJECT: FUEL INJECTION TUBELINES This Service Bulletin replaces Service Bulletin 900-009 dated 14 June 1984 Current production Bobcat loaders have redesigned tubelines The new tubelines can be identified by the shape of the banjo fitting at the injection pump end (Fig 1 ) The new part numbers are as follows · Ref No (Fig 2) Part Number Description 900-009 Bulletin Number 29 June 1985 Date ROUTE TO ATTENTION  0  0  D D Additional information about this subject is found in the following: Service Letter BTI Bulletin         Installation Instr Manual Revision Taper DATE: MODEL: SUBJECT: BOBCAT 8 July 1985 2500 Hydraulic Breaker Main Body Bolt Torque DIRECT TO: CB' D CB" D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The four long bolts which hold the main body sections of the hydraulic breaker together must be tightened to 600 ft-lbs (814 Nm) torque Put oil on the threads before installing the bolts The torque was incorrectly stated in the model 2500 Breaker Operator's Manual The manual is being revised to specify the correct torque Printed in USA BOBCAT DATE: 9 July 1985 MODEL: 540, 640, 740, 843, 943 SUBJECT: Cab Door Gas Spring Mounting (Kit #6568712 & 6568976) DIRECT TO: rn-' rn-' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst 6566956 Manual Revision When installing the gas spring for the cab door, be sure that the cylinder rod (Fig 1, Item 1) is fastened to the angle bracket (Fig 1, Item 2) as shown in figure 2 Use care when tightening the nut        , «P---, ,/' /  ,,   /Qt-:-o , / ----:1f il /---· 2 I '-1 r------- ,    J ------ ,-1--------------/ --¥f-, ) I I ,,    ---, ,, I f I / I I I / I I I I f:J--f---o ,,/ I I t 1/ ' ' ! E-1648 Figure 1 Figure 2 Printed in USA If the angle bracket (Fig 1, Item 2) is bent, replace it with a new bracket, P/N 6568055 The gas spring is not repairable If it is damaged in any way it must be replaced Gas cylinder holds the rod under high pressure Never attempt to open the ' cylinder &WARNING  only DIRECT TO: BOBCAT  D D D D D DATE: 10 July 1985 	Additional information about this subject is found in the following: I MODEL: 825 Service Bulletin        BTI Bulletin         SUBJECT: Crankshaft Failure Installation Inst Manual Revision Engine crankshaft bearing failure can result if the engine is not correctly grounded to the main frame Since the engine is mounted on rubber mounts a ground cable is required between the engine and mainframe to assure proper electrical operation If the ground connection has not been properly maintained, electricity will travel through the crankshaft main bearing, flywheel and u-joint to find ground This may result in failure of the main bearing A 4 gauge cable must be maintained from the engine block to main frame See Service Letter dated 6 February 1980  only No warranty is allowed Printed in USA BOBCAT DATE: 11 July 1985 MODEL: 730, 740, 843 (Series) SUBJECT: Gearbox Input Shaft -P/N 6558277 (730's, 740's); 6558278 (843) DIRECT TO: [13"' [13"' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin ---'-"----­ Installation Inst Manual Revision Some loaders may have gearbox input shafts which are too long If the shaft protrusion (Figure 1) is more than 476" (12,09 mm), it may interfere with the hydrostatic motor housing This can result in galling of the geroler parts and motor failure B-7840 Figure 1 Anytime a motor is replaced, check the shaft protrusion per figure 1 before installing a new or remnufactured motor The shaft protrusion must be measured from the motor mounting face on the gear box to the end of the shaft If the shaft length is more than 476" (12,09 mm) the shaft must be shortened by grinding NOTE: 	This is not the only cause for motor galling, so be sure to check dimensions carefully  only No warranty is allowed Printed in USA BOBCAT DATE: 7 August 1985 MODEL: All Gasoline Engine SUBJECT: Low Lead Gasoline DIRECT TO: []f"' []f"' 0 · 0 0 D 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The final Environmental Protection Agency ruling reduces the lead content of leaded gasoline to 1 gram per gallon by January 1, 1986 This translates to 9% of the leaded content currently used This also means that leaded gasoline is not being totally eliminated The use of gasoline with lower lead content is not expected to have an adverse affect on engine life or performance, although the rate of valve seat wear may increase on engines which do not have hardened seats Kohler recommends lead free fuel since their engines all use stellite valves and hardened seats Ford engines in currently built Bobcat Loaders use stellite valves but seats are not hardened Low lead gasoline can be used on these engines with little effect on valves The octane level of regular leaded gasoline is 89 If the new 01 gm/gal lead gasoline maintains this octane level, engine performance should not be affected However, if a lower octane level gasoline is used, ignition initial timing may have to be retarded to elimate detenation and this could result in loss of power DATE: MODEL: SUBJECT: BOBCAT 8 August 1985 825, 843, 974, 1074, 1080 (Perkins), 2000, RTF Cylinder Head Bolt Retightening DIRECT TO: Dr"' Dr"' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision       Whenever the cylinder head has been removed and reinstalled, the engine must be " run-in" and the cylinder head bolts retightened It is essential that engine be warmed up under a partial load for about one half hour before retightening the bolts This is necessary so that the cylinder head and gasket reach their correct positions during run-in The valve clearance must also be readjusted after retightening the head bolts This procedure does not require engine removal Printed in USA DIRECT TO: []""" BOBCAT []""' 0 0 0 0 0 DATE: 9 August 1985 	Additional information about this subject is found in the following: MODEL: M-500 Service Bulletin        BTI Bulletin        SUBJECT: Flywheel For Kohler Engine Installation Inst Manual Revision Manufacture of flywheel, part number 6517193, has been discontinued and is no longer available as a service part This flywheel was used on generator equipped engines Flywheel, part number 6517192, will continue to be available and can be used on engines formerly equipped with a generator However, it will be necessary to install the jackshaft driven alternator kit (P/N 6506492 on the loader since the generator cannot be used when flywheel (P/N 6517192) is installed Parts Fiche will be updated to reflect this information Printed in USA BOBCAT DATE: 15 August 1985 MODEL: 440 thru 843, 1600, 2000 and RTF SUBJECT: Seal Replacement in Melroe Valve Installation Procedure: 1 Remove the valve from the machine 2 Remove the spools from the valve DIRECT TO: ffi" ffi" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision 3 Remove the detent and centering springs from the spools 4 Remove the spool seals from the valve 5 Check the spool for sharp corners where the rubber boot fits in front, and also check the back of the spool (A, Item 1) Use a file to remove the sharp corners D-1385 6 	 Install the front seals first (P/N 6632204) 7 	 Push the spools into the control valve from the rear just so that the rear seal can be installed Push the spool to the rear again until the spool is flush with the machined surface of the valve -1-	Printed in USA  ' 8 Put plastic plugs in the work ports and plug, P/N 891203 in the inlet port Install an air hose fitting in the return (outlet) port of the valve 9 Apply 10-15 PSI (69-103 kPa) air pressure to the return port of the valve Control the pressure with a regulator 10 Put the valve in a pan of oil Cover the valve with oil and check for leaks around the spools (A) - 11 	If there are no leaks, install detent and centering springs and install the valve in the machine  only Warranty will be allowed for units,)'ithin the warranty period Allowable service times are as follows: Model Rand R Repair Pressure Check Total 440, 443 2-1/2 hours 1 hour 1/2 hour 4 hours 540, 543 5 hours 1 hour 1/2 hour 6-1/2 hours 641, 642, 643 5 hours 1 hour 1/2 hour 6-1/2 hours 741, 742, 743 6 hours 1 hour 1/2 hour 7-1/2 hours 843 4 hours 1 hour 1/2 hour 5-1/2 hours 1600 3-1/2 hours 1 hour 1/2 hour 5 hours 2000, RTF 3-1/2 hours 1 hour 1/2 hour 5 hours -2­ BOBCAT DATE: 16 August 1985 MODEL: 540, 640 (Series) SUBJECT: Hydrostatic Motor Shaft Seal DIRECT TO: ar" ar" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision NOTE: 	This Service Letter Replaces Service Letter, subject; "Shaft seal for hydrostatic motor, 6599718", dated 5 March 1984 A new motor shaft seal with brass backup ring is now being used in the hydrostatic motor, 6630037 The new seal replaces the seal formerly used on spline shaft and tapered shaft motors, 6630037 and 6599718 (model numbers 109-1052-006 & 109-1173-006) A new seal kit is available which contains the new seal plus the other seals used in the motor The new seal kit part number is 6632040 and will service all -006 motors Seal kit, 6598463, will still be available for earlier motors (model numbers 109-1052-004 & 109-1052-005) NOTE: 	Please refer to the special tool required for installation of shaft seals (see reverse side) Printed in USA A special seal assembly tool is required to install the new shaft seals The tool can be locally manufactured per dimensions shown below If a bushing and bearing driver tool set is available, use a 1625" and 2125" combination to install the seal  only; not a field modification BOBCAT DATE: 19 August 1985 MODEL: 1600, S/N 11249 & Above; 2000, S/N 13190 & Above; RTF, S/N 15023 & Above SUBJECT: Hydrostatic Motor With Shaft Bearing Retention Improved DIRECT TO: !Jr" !Jr" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision       New hydrostatic motors with improved shaft design are installed on present production machines beginning with serial numbers listed above The bearing retention area has been changed to incorporate changed parts: Items changed are: (figure 1) 1 Shaft with revised grooves for retaining rings 2 Rear bearing retaining rings 3 Rear bearing retaining washers, with chamfer Figure 1 Printed in U Shaft kits are available for servicing all machines and must be used whenever shaft replacement is necessary Part numbers for these kits are: Model Machine Serial No Kit Part Number 1600 All 6631700 2000 13060 & Below 6631699 2000 13061 & Above 6631700 RTF 15020 & Below 6631699 RTF 15021 & Above 6631700 The kits contain one shaft, two retaining washers and two retaining rings  only Not a field modification BOBCAT DATE: 26 August 1985 DIRECT TO: CB"' CB"' D D D D D Additional information about this subject is found in the following: MODEL: 1600, 2000, RTF Service Bulletin        BTI Bulletin         SUBJECT: Brake Failure Installation Inst Manual Revision Brake assembly failure may be caused by a loose pedal which partially engages the brake during operation of the loader The pedal should be fully released when brake is not being used If the return spring does not hold the pedal fully released the pedal may "bounce" while machine is in motion This would cause the brake to intermittantly engage and result in undo stress and increased wear of internal parts If the pedal spring does not firmly hold the pedal fully released check the spring (6505076) If it has been overstretched or is broken, replace it Add a extension tab to the pedal to give the spring more leverage  only No warranty is allowed BOBCAT DATE: 27 August 1985 MODEL: All (Except 900-1000 Series) SUBJECT: Solenoid (551530) DIRECT TO: CB" CB" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin        Installation Inst Manual Revision Solenoid part number, 551530, has been replaced by 6631939 (Delco) as a service replacement part Please order solenoid (6631939) instead of 551530 when ordering a replacement part Parts fiche revision to reflect this change is currently in process  only No warranty is implied DIRECT TO: ar' BOBCAT ar' D  D D D FIELD MODIFICATION D DATE: 28 August 1985 	Additional information about this subject is found in the following: MODEL: 2500 Hydraulic Breaker -S/N-0194 Service Bulletin        through 0626 BTI Bulletin             Installation Inst Manual Revision       SUBJECT: Operational Performance The model 2500 hydraulic breaker may exhibit slow impulse rate or stopping If this situation occurs, make the following checks: 1 Check Bobcat loader hydraulic flow and system relief valve Refer to Service Manual or Technical Service Guide for procedure and specifications for loader model which breaker is installed on 2 Check charge in main nitrogen chamber Pressure must be 400 PSI (maximum) Check 850 and 100 PSI accumulators also 3 Check hydraulic back pressure by installing a 1000 PSI pressure gauge in the return hose to the quick coupler Back pressure during breaker operation should not exceed 400 PSI 4 If above checks are good, disassemble the breaker and replace the valve (P/N 6631666) and valve cylinder (P/N 6331667) with kit, part number 6632188 The kit contains all necessary parts and seals Installation instructions are included and must be followed when installing the parts To order kit P/N 6632188, call (701) 678-6484 -Melroe Service Department in Gwinner Replaced parts must be returned undamaged tq Melroe Use the container which kit parts were shipped in to return the used parts Parts must be packaged carefully to prevent nicks or scratches on critical surfaces CREDIT WILL NOT BE ISSUED UNTIL PARTS ARE RETURNED UNDAMAGED Melroe will give compensation for the cost of the kit plus 3 hours labor for installation One additional hour is allowed for travel time for retailed machines Printed in USA BOBCAT DATE: 17 September 1985 MODEL: 2500 Hydraulic Breaker SUBJECT: Installing Seals On Valve Cylinder DIRECT TO: IB" IB" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The poly-pak seals must be correctly installed on the valve cylinder or the breaker will not operate properly The seals, 6630673 and 6630672, are of different diameters The diameter difference is not easy to detect, therefore, care must be used to measure them to insure that they are installed in the correct locations The size difference can be most easily seen by placing both seals on a pencil and comparing them (figure 1) Figure 1 + 1/8" Size Difference -1-Printed in USA Install the smallest seal (5-1/8" OD) in the lower groove of the valve cylinder Install the largest seal (5-1/4" OD) in the upper groove of the cylinder (figure 2) The open sides of the seals must face toward each other (See detail in figure 2) Figure 2 Seal kit, 6630787, contains these seals, plus the other seals used in the breaker  only No warranty is implied BOBCAT / DATE: 23 September 1985 MODEL: 2500 Hydraulic Breaker SUBJECT: Plugs For Nitrogen Charge Valves DIRECT TO: CB"' CB"' 0 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The nitrogen charge valves (6630633) are susceptible to dirt and moisture and must be protected by the threaded plugs (6630682) provided It has been observed that sometimes the plugs have not been re-installed by servicing personnel after charging the accumulators This has resulted in corroded and dirty valves which may render them defective Always install the plugs after servicing the accumulators The above is provided for technical information only Printed in USA BOBCAT DATE: 9 October 1985 MODEL: 540, 640, 740 (Series) SUBJECT: Sight Glass In Hydraulic Reservoir DIRECT TO: ar ar ar D D D D Present production Bobcat loaders listed above have a sight glass for checking the hydraulic reservoir fluid level Some earlier units had a reflective "star" within the glass to enhance viewing The "star" was later discontinued and presently is not used Some leaking around the sight glass has been reported If this is a problem, remove the glass plug and install a new 0-ring, P/N 25K-40030 Tighten the glass plug securely but be careful not to over tighten it  only lllELROEcoMPANT bobcat -----· GENERAL --SERVICE BULLETIN iiiiiiiiiiiiiii AFFECTING: Product BOBCAT LOADER 0 Model 611, 631, 632, 721, 722, 731 and 732  0 D Serial No D Manual No SUBJECT: 	SOLDERING CARBON BRUSHES TO ALUMINUM COILS OR BOSCH STARTER This General Service Bulletin replaces bulletin number G-006 dated 9 February 1982 Destroy the old bulletin and replace it with the updated copy The carbon brushes you ordered from Melroe Parts Sales have no connection cables The new brushes must be soldered to the 	connection cables (pigtails) leading to the positive and ("'\ negative brushes Use the following procedure to solder the new brushes to the connection cable: 1 	Destroy the old worn brushes connected to the existing cables by breakin!tJhem with a hammer or by crushing them with a vise /'"', A WARNING Safety glasses or goggles are always needed for eye protection from fluids under pressure, flying debris or loose material when engine is running or tools are used Failure to obey warnings can cause injury or death W-2019-0284 2 	 Scrape the ends of the cable clean with a knife 3 	 Insert the clean end of the cable into the hole in the replacement brush and spread the strands out in the countersink on the other side [i] 4 	 To support the brush during soldering and to prevent the solder from moving up in the strands of the cable, hold the cable with a pliers just behind where it enters the brush 5 	 Use solder that is a mixture of 50% tin and 50% lead and a soldering iron with a power rating of 250 to 350 watts Soldering paste is recommended as flux w ith alcohol or trichloroethylene after soldering 6 	 File the solder off even with the surface of the brush 7 	 Check for free movement of the brush in the brush holder A BUSINESS UNIT OF CUlllll EQUIPMENT COMPANY 	Printed in USA DIRECT TO: cY BOBCAT cY cY D D D D DATE: 	11 November 1985 MODEL: 	640, 740, 843 & 943 (Serial Numbers Listed Below) SUBJECT: 	Hydrostatic Filter Bypass & Pressure Switch Change 641 -S/N 20166 & Above 642 -S/N 20481 & Above 643 -S/N 20525 & Above 741 -S/N 20129 & Above 742 -SIN 20401 & Above 743 -S/N 22873 & Above 743 DS -S/N 51061 & Above 843 -S/N 20992 & Above 943 -S/N 11085 & Above (#3 element filter) 943 -S/N 11210 & Above (#4 element filter) The hydrostatic filter assemblies for the serial number loaders listed above have a 50 PSI bypass valve and a 40 PSI hydrostatic pressure switch The higher pressure rating of the switch prevents cold (thicker) oil from turning on the transmission warning light during cold weather start-up A filter head with the 40 PSI pressure switch can be identified by the red/white washer located under the terminal nuts The filter head with the formerly used 19 PSI switch has a green washer under the terminal nuts The bypass valve has the pressure rating stamped into the poppet, inside the filter head The new filter assembly (50 PSI bypass valve and 40 PSI switch) part5 number is (with element); 6631706 The 40 PSI pressure switch is; 6632053 <: The #4 element filter assembly (50 PSI bypass and 40 PSI switch) us:h (  ,in the 943 is part number 6631969 J The above is provided as product improvement only No warranty is allowed Printed in USA BOBCAT DATE: 12 November 1985 MODEL: Farmboy, 440, 443 SUBJECT: Chaincase Fluid Capacity DIRECT TO: Cll"" Cll"" Cll"" D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision To insure continueous lubrication of the axle bearings, the chaincase oil capacity has been increased to 4 gallons The check/fill plug will be relocated on future production Bobcats to accomodate the added capacity On earlier built machines, to determine the correct level of fluid in reservoirs with the added volume, raise the front of the loader until the end of the chaincase is about 8 inches off the floor (a plank, 1-1/2" thick under each tire will also work if tire tread is like new) Fluid level should be near the check/fill plug when volume is at 4 gallons The above is provided as product inprovement information only No warranty is allowed Printed in USA BOBCAT DATE: 19 November 1985 MODEL: 1600, S/N 11240 & Above 2000, S/N 13198 & Above RTF, S/N 15026 & Above SUBJECT: Neutral Start Switch I DIRECT TO: CB""' rn-"' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision Beginning with the above serial number machines, present production articulate Bobcat loaders feature an improved neutral start/backup alarm switch The new switch assembly uses cam actuated micro switches, mounted at the side of the centering mechanism The improved switch assembly can be installed on earlier built machines Kit number 6584603 contains the necessary parts and instructions to install the new switch assembly This kit can be ordered from Melroe Parts marketing at Chicago No warranty is allowed A continuity tester, MEL-1273, is available from Owatonna Tool Company This tester is designed to be used in adjusting the neutral start/backup alarm for proper operation The tester can be used on machines with either the current micro switch assembly or the formerly used push-pull (sliding) switch assembly Use the following procedures for using the tester: Micro Switches Assembly: 1 With the centering mechanism lead disconnected from the harness plug, plug the tester into the switch connector The interlock system should be in the un-latched position (seat bars down) Disconnect the linkage to the servo spool 2 Green 	light indicates when the neutral switch will allow the engine to be started To adjust, move the switch mounting plate along the slots to set the neutral start micro switch in the "ON" position -1­ Printed in USA NOTE: 	Lighter pressure between the cam lobe and the neutral switch activator makes the neutral switch MORE sensitive Also, rotating the cam lobe allows the switching to be centered equally, forward or reverse, before the neutral switch deactivates 3 	Red light indicates when the backup alarm switch will allow the backup alarm to sound This should be set automatically when the neutral start switch is adjusted as noted in Item #2 NOTE: 	Red and green lights should not be on at the same time! Red should be activated just as the green light goes off when the mechanism is rotated in the reverse travel direction Slide Switch Assembly: 1 	 With the centering mechanism lead disconnected from the harness plug, plug the tester into the switch connector The interlock system should be in the un-latched position (seat bars down) Disconnect the linkage to the servo spool 2 	 Green light indicates when the switch will allow the engine to be started To adjust, slip down the boot covering, loosen the jam nut on the switch shaft and rotate the switch shaft until the light indicates that it is centered in the "ON" position Secure with the shaft jam nut and reinstall the boot 3 	 Red light indicates when the switch will allow the backup alarm to sound This will be set automatically when the neutral start switch is adjusted, as noted in Item #2 -2­ BOBCAT DATE: 22 November 1985 MODEL: 440 Thru 843, 1600, 2000 SUBJECT: Seal For Valve Spool (Melroe Valve) DIRECT TO:  D 0 D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision Spool seal, part number 25K-30020, has been replaced by an improved quadring seal part number 6632204 Dealerships are advised to order and stock the new seal for servicing Melroe valve spools Seal kits will be updated Meanwhile use only the quadring when servicing the valve spool Be sure to lubricate the seal before installing it Refer to service letter, dated 15 August 1985, for procedure for repair of valves with leaking spool seals The new seal is available at Melroe Parts Marketing, Chicago, IL Figure 1 Ouadring Seal Printed in USA BOBCAT DATE: 10 February 1984 MODEL: 313, 443 SUBJECT: Kubota Engine Valves DIRECT TO: EB" CB" 0 0 0 0 0 Additional information about this subject is found in the following: D Service Bulletin       D BTI Bulletin        D Installation Inst      D Manual Revision The current parts microfiche shows wrong part numbers for the engine intake and exhaust valves The valves, 6599009 (intake) and 6599010 (exhaust) shown in the 313, 443 microfiche are for the Model 543 Kubota engine only Listed below are the correct part numbers for the Model 313 and 443 Kubota engine valves: Model Valve Part Number 313 313 Intake Exhaust 3974157 3974158 443 443 Intake Exhaust 6630679 6630680 Microfiche correction cards are being prepared to advise your parts department of the correction DIRECT TO: 113"' BOBCAT 113"' 0 0 0 0 0 DATE: 22 February 1984 Additional information about this subject is found in the following: MODEL: 540, 640 Series Service Bulletin        BTI Bulletin SUBJECT: Shaft Seal for Hydrostatic Motor, Installation Inst 6599718 Manual Revision An improved shaft seal is available to us in place of the seal contained in seal kit 6598463 This new seal is for motor 6599718 (model 109-1052-006) To repair a motor with only a leaking shaft seal order the following parts: 6630795 Shaft Seal 6630796 Dust Seal 6513535 0-Ring If more extensive repair to the motor is being made and the complete seal kit is used, order 6598463 (seal kit) PLUS the new shaft seal, 6630795 Use the new shaft seal (6630795) instead of the one contained in the kit This applies to the 6599718 motor only (Seal Kit, 6598463, also contains seals for earlier motor, model 109-1052-005) -1­ Printed in USA - Shaft Seal for Hydrostatic Motor, 6599718 A special seal assembly tool is required to install the new shaft seals The tool can be locally manufactured per dimensions shown below: If a bushing and bearing driver tool set is available, use a 1625" and 2 125" combination to install the seal  only; not a field modification -2­ DIRECT TO: [B"' BOBCAT [B"' D D D D D DATE: 5 March 1984 	Additional information about this subject is found in the following: MODEL: 540, 640 Series Service Bulletin        BT I Bulletin SUBJECT: Shaft Seal for Hydrostatic Motor, Installation Inst 6599718 Manual Revision This Service Letter Dated 5 March 1984 Replaces Service Letter Dated 22 February 1984 An improved shaft seal is available to use in place of the seal contained in seal kit 6598463 This new seal is for motor 6599718 (model 109-1052-006) To repair a motor with only a leaking shaft seal order the following parts: 6630795 Shaft Seal 6630796 Dust Seal 6513538 0 -Ring If more extensive repair to the motor is being made and the complete seal kit is used, order 6598463 (seal kit) PLUS the new shaft seal, 6630795 Use the new shaft seal (6630795) instead of the one contained in the kit This applies to the 6599718 motor only (Seal Kit, 6598463, also contains seals for earlier motor, model 109-1052-005) -1-	Printed in' USA Shaft Seal for Hydrostatic Motor, 6599718 A special seal assembly tool is required to install the new shaft seals The tool can be locally manufactured per dimensions shown below: If a bushing and bearing driver tool set is available, use a 1625" and 2 125" combination to install the seal  only; not a field modification -, DIRECT TO: IV, BOBCAT 113"' rEr I r , i ! -1 l : DATE: 6 March 1984 MODEL: 843 S/N 15001 & Above SUBJECT: New Operator's Manual 6566611 (1-84) Additional information about this subject is found in the following: Service' Bulletin        BT I Bulletin Installation Inst Manual Revision The Operator's Manual, 6566611, has been updated to include additional information pertaining to this series loader This new manual replaces the manual shipped w ith machine serial numbers 15001 thru 15800 According to our records the following serial number machines were shipped to your dealership: The manuals sent with this letter are provided as replacements Please rernove the Operator's Manual from the delivery package (behind the seat in operator's cab) and put the new manual in its place Do this on machines still at your dealership A s for machines which have been retailed, Melroe is sending the owners replacement manuals and asking that the old manuals be disposed of If additional manuals are needed, please order them from Central Parts Division, Chicago, IL - Printed in USA BOBCAT DATE: 7 March 1984 MODEL: 440, 540, 640, 740, 843 (Series) SUBJECT: Hydraulic Fluid DIRECT TO: D D D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision       The recommended hydraulic fluid for Bobcat loaders is the Clark "Black Gold" fluid, part number, 6563328, (5 Gallons) The black gold fluid is an "all season" fluid, suitable for ambient temperature conditions ranging from sub zero to + 100°F (+38°C) In circumstances where the "Black Gold" fluid is not immediately available, a multi grade SE/SF engine oil can be used as alternate fluid For ambient temperatures of 0°F (-18°C) and below, SAE 5W-30 should be used For above 0°F (-18°C) temperature conditions, SAE 10W-40 should be used Changes are being made to the Operator's and Service Manuals to reflect these recommendations Printed in USA BOBCAT DATE: 8 March 1984 MODEL: 7 41 -15118 thru 1 51 28 743 -16645 thru 16778 SUBJECT: Gearbox Input Shaft (6558272) DIRECT TO: CB" CB" D 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision The spline bore depth in the gearbox input shaft must not exceed 2 5937" (65,87 mm) If the measured depth is greater than this specification the shaft must be replaced If the spline bore is too deep, failure of the hydrostatic motor would result If the motor failure is due to spline teeth sheared off at the geroller end of the motor shaft (651 3506) also check the spline bore depth in the gearbox input shaft Warranty consideration will be allowed as specified in the current Service Policy and Procedure Manual BOBCAT DATE: 9 March 1984 MODEL: 	540 543 641 642 643 -S/N 13072 & Above -S/N 13082 & Above -S/N 13341 & Above -S/N 13941 & Above -S/N 13620 & Above I DIRECT TO: EB" EB" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision SUBJECT: Spline Shaft Hydrostatic Motors Hydrostatic motors with spline shafts are now being installed on present production loaders listed above Service time is greatly reduced when removing these motors since the chain case does not need to be opened and the chains removed New parts used are as follows: Description Spline Shaft Motor Cluster Sprocket Screw Washer Nut Snap Ring Part Number Qty 6630037 2 6565185 2 6564741 8 6564740 8 860-8 8 791442 2 The new parts are available through Clark Central Parts Division, Chicago, IL Please establish parts requirements so that you are prepared to support your customers needs for the parts  only No warranty is implied Future service 	and parts literature will reflect this change Printed in USA BOBCAT FIELD MODIFICATION DATE: 14 March 1984 MODEL: 7 41 -15118 thru 1 51 28 743 - 16639 thru 16778 SUBJECT: Gearbox Input Shaft Inspection DIRECT TO: CW CW D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision An inspection of gearbox input shafts (p/n 6558272) must be made to prevent possible failure of the hydrostatic motors Only machines which have accumulated less than 200 operating hours need to be checked The spline bore depth in the gearbox input shaft must not exceed 2 5937" (65,87 mm) If the measured depth is greater than this specification the shaft must be replaced Motor failure results in spline teeth being sheared off at the geroller end of the motor shaft (6513506) If this type of failure occurs, be sure to inspect the gearbox shaft when making repairs Melroe will give compensation for two hours labor per machine to complete the inspection Labor time allowed for the gearbox shaft replacement, (if necessary) is as specified in the suggested Service Times Section of the current Service Policy & Procedure Manual, 6556743 One additional hour is allowed for travel time for retailed machines This policy will expire on 31 May 1984 Printed in USA BOBCAT FIELD MODIFICATION SAFETY NOTICE DATE: 16 April 1984 MODEL: 440, S/N 11491 & Below 443, S/N 11359 & Below DIRECT TO: CB" CB" 0 0 ri o 0 Additional information about this subject is found in the following: Service Bulletin         BTI Bulletin Installation Inst Manual Revision For instructions to operators for the safe dismounting from the 440 series Bobcat Loader, the safety sign decal, 6568646 must be installed in the operator cab (Figure 1l According to our records the following serial number machine(s) were shipped to your dealership and are not yet retailed: Please install the enclosed decal(s) on the inside of the operator cab, to the right of the seat (Figure 2) A WARNING AMONESTACION   WARNUNG AVERTISSEMENT BEFORE LEAVING LOADER: 1 	 LOWER LIFT ARMS 4 MOVE PEOALS UP AND DOWN UNTIL LOCKED 2 TURN ENGINE ')ff 5 	PUT BRAKE DN 3 RAISE SEAT BAR 6 	UNFASTEN SEAT BELT See Opereco( M nuI for more in1Huc1ton1 Feilure 10 obey werning1 may cau1e injury or dea1h Wei1e1a lnsttutuionan Sind 1n der Bedlenung1anle11ung Mi1aachtung dieter Aagain kann Verleuun9 "'arursachan und 11ann TOdlich 1eln Consult el Manual del Operador par mas 1n1trucc10nas El no obedecer euo1 1v1so1 pueda cauaar heride1 o 1er fatal Sa reporter au manual de 1·opr11aur pour plus "11gne man11 Le non·111pac1 da1 prkap111 peut enttlner de1 ble11ure1 ou l11 m ort Figure 1 -1-	Printed in USA If any of the serial number machine(s) listed above have already been retailed to a customer, please arrange to have the decal installed at once Melroe is also notifying customers which our records show as having purchased a 440 series Bobcat in the serial number ranges listed at the top of this letter The decal is included in the notification and instruction is given for customers to install the decal on these loaders Melroe will give compensation for 1 /2 hour labor to install the decal on each serial number machine at your dealership One additional hour is allowed for travel time for retailed machines -2­ BOBCAT DATE: 18 April 1984 MODEL: 540, 640, 740, 843 Series SUBJECT: Retouch Painting DIRECT TO: CB"' CB"' CB"' D D D D Additional information about this subject is found in the following: Service Bulletin    G - 0 08   BTI Bulletin Installation Inst Manual Revision SERIAL NUMBER: 	This service letter pertains to the following serial number machines only 540-13072 thru 13091; 543-13108 thru 13147; 641-13311thru13335; 642-13910 thru 14007; 643-13621 thru 13687; 742-15419 thru 15477; 743-17150 thru 17407; 743 DS-50119 thru 50136; 843-15806 thru 15873 Serial number machine(s) listed above which have paint peeling problems should be repainted with Melroe specification water reducible enamel Repaint only those areas where paint peeling or rust bleed through is occuring This paint is specially formulated for touch up over the polyurethane paint used on Bobcat loaders Mel roe will provide one ( 1) gallon of the special paint for each serial number loader listed above which has a paint peeling problem Dealers are requested to contact the Melroe Service Department, Telephone Number 701-678-6484, to report paint peeling problems Warranty compensation will be given for labor time needed to complete the retouch painting, as described below This policy will apply only to machines with paint peeling problems within the range of serial numbers listed above For procedure, see reverse side -1-	Printed in USA Procedure for retouch painting: 1 	 Remove loose paint with a high pressure washer or light sanding in effected areas 2 	 Machine surfaces to be painted must be at least 60°F Surfaces should be dry and dust free 3 	 The water based enamel can be applied with air or airless spray equipment In some cases, small areas can be touched-up with a small bristle brush 4 	 Reduce the paint with tap water only! Do not use solvents The amount of reduction will depend on the applicator, type of equipment used and spray booth climate The product can be applied unreduced, dependent on equipment or application method 5 	 The water based enamel should be dry to touch in 3-4 hours and completely dry overnight 6 	 Do not let the water based enamel freeze and thaw repeatedly Properly stored water based enamel has a shelf life of 1 year 7 	 The water based enamel does contain small amounts of thinners and therefore will burn! Flash point is 165°F 8 	 Painters should use protective clothing, goggles or safety glasses, and disposable type air masks as they would with any other type of paint being sprayed 9 Application equipment can be cleaned with water or mineral spirits -2­ CUFIRK Melroe Division GENERAL ---SERVICE BULLETIN iiiiiiiiiiiiiii AFFECTING: Product BOBCAT LOADER Model 540, 640, 740, 843 SERIES Serial No SEE LIST BELOW G-008 - r 19 April 1984 Manual No SUBJECT POLYURETHANE PAINT REFINISHING WITH WATER REDUCIBLE PAINT The following Serial Numbered and Later Bobcat loaders are coated with polyurethane paint 540 -5010-M-13092 741 -5017-M -15159 543 -5024-M-13156 742 -5018-M -15523 641 -5013-M-13336 743 -5019-M -17417 642 -5014-M-14067 743 OS -5025-M-50137 643 -5015-M-13733 843 -5026-M-15909 Additional information about this subject is found in the following : Service Letter 18 APR 84 BT I Bulletin Installation Instr Manual Revision Polyurethane paint has a finish that is more scratch resistant and presents a more durable finish with a longer-lasting gloss than other paints Water reducible alkyd paint is designed for touch-up or refinishing of polyurethane painted loaders The water reducible alkyd paint is also suitable for use on Bobcat loaders prior to the serial numbers listed Water reducible alkyd paint, thinner and primer is available from Clark Melroe Parts in Chicago under these P/N's: 6568573 White 1 Liter Container 6568579 Yellow Liter Container 6568574 White 4 Liter Container 6568580 Yellow 4 Liter Container 6568575 Orange Liter Container 6568648 Reducer 4 Liter Container 6568576 Orange 4 Liter Container 6568649 Primer Liter Container 6568577 Grey Liter Container 6568663 Primer 4 Liter Container 6568578 Grey 4 Liter Container TOUCH-UP PREPARATION FOR WATER REDUCIBLE PAINT Because of the " slick" finish of polyurethane paint, scratches and chips cannot be touched up in the usual manner In most cases, the entire surface must be lightly sanded in all directions from the scratch or chip to some break point on the Bobcat loader The edges of the scratch or chip must be feathered and, if the damage is deep, fillers must be used to level the surface at the point of damage Do not grind the paint down to bare metal Use a 240-grit silicone carbide paper for sanding, and remove all sanding dust before applying wet paint REFINISHING PREPARATION FOR WATER REDUCIBLE PAINT If it becomes necessary to refinish a complete Bobcat loader (painted with polyurethane), this can be done within a few days of the original factory application of polyurethane paint without any special preparation (other than removing dirt and oil) However, after about two weeks, the paint hardness has increased to a point where the paint surface cannot be recoated without preparation to insure adhesion of the new coat To prepare hardened polyurethane paint, the entire surface must first be deglazed or " scuff sanded" with 240-grit silicone carbide paper Sand only enough to remove the scratches and the " slick" finish Avoid grinding down to bare metal unless rust is present -Any bare metal must be primed with polyurethane-compatible primer Order the primer from chart above Remove all sanding dust with a solvent-moistened rag The primer can be applied over bare metal or sanded polyurethane paint The primer must be allowed to dry before recoating, according to the instructions on the primer can -1-Printed in USA Temperature and humidity can effect the drying time of the paint The ideal conditions are: Dry to Touch -----3 -4 hours@ 70°F (21°C) with 50% Humidity Dry Through ------12 hours @ 70°F (21 °C) with 50% Humidity Anyone handling water reducible alkyd paints must be protected with coveralls, respirator, goggles and gloves Any exposed skin surface must be coated with protective skin cream, which later can be washed off with soap and water This paint is specified for Melroe machines Do not use on other surfaces exposed to children Failure to obey warnings can cause injury or death APPLICATION As with any paint, the surface to be painted with water reducible alkyd paint must be thoroughly cleaned of all dirt, rust, loose paint, oil and grease See " Refinishing Preparations" for the correct procedure Water reducible alkyd paint can be applied by using either the air or airless atomizations spray equipment It is important to clean the spray equipment immediately after use to prevent set-up of the paint Use thinner (P/N 6568648) to clean the equipment PAINT FACILITIES AND PERSONNEL PROTECTION Use a paint booth which conforms to regulations applicable in your area The personnel protection required is that all exposed skin areas must be protected with skin cream Gloves may be used to protect the hands Goggles must be used to protect the eyes The requirement for respirators and complete hand coverings are covered by regulations applicable in your area It is very important that people, in and around the area where any paint is being used to be protected for their own health as well as for compliance with regulations GENERAL When welding on the surfaces where the paint is affected by the heat there will be some gases released which may be toxic This is true of any paint, including polyurethane, so it is recommended that a respirator be worn by the welder if there is to be any welding done under these conditions When grinding polyurethane or other paints, it is recommended that respirators be worn to prevent inhalation of the paint dust Water reducible alkyd paint has a flash point of approximately 165°F (74°C) -2­ PAINT SPECIFICATIONS WATER REDUCIBLE ALKYD ENAMEL Finish High Gloss Calculated Coverage@ 1 Mil Thickness 726 sq ft/gal (14,8 sq m/litre) Application Air or Airless Spray Pot Life Not Applicable Dry Time Dry to Touch: 3 -4 hours@ 70° F (21 ° C) with 50% humidity Dry for Use: 12 hours@ 70°F (21 ° C) w ith 50% humidity Application Condition Apply only when air and surface temperatures are 45 -100°F (7 -38 °C) Application Procedure Apply in wet coat making even parallel passes Overlap each pass 50% to minimize bare areas or pin holes Recommended Thinning Distilled Water or Thinner Solution (P/N 6568648) Cleaning Equipment Thinner Solution (P/N 6568648) Refinishing Preparation Clean the surface of all dirt, loose paint, rust, oil and grease The surface must be deglazed or " scuff sanded" with 240-grit silicone carbide paper Sand only to remove "slick" finish Remove paint dust Flash Point Approximately 165°F (74°C) Extinguishing Media Dry chemicals, carbon dioxide, foam or " Class C" extinguishing equipment Shelf Life One year from manufacturing date when stored indoors DO NOT FREEZE Handling and Storage All containers must be tightly closed to avoid spilling while handling M aterial must be stored in a dry place and storage temperatures must be between 50°F (10°C) thru 104°F (40°C) Overexposure Effects Irritation to the nose, throat, lungs and eyes May also cause headaches and dizziness Respiratory Protection Material must be sprayed at a place equipped w ith exhaust system Proper air filtration mask (carbon cartridge), air feed hoods must be used Ventilation (Type) Exhaust system Must have sufficient capacity to keep solvent vapors below 20% of explosive limit of 25% volume of solvent vapor in air First Aid Procedure Eyes: Flush with large amounts of water for 15 minutes and get immediate medical attention Skin: Wash thoroughly with soap and water Inhalation: Breath fresh air and move away from area Spill or Leak Procedure Eliminate all ignition sources and clean up the area w ith rags, saw dust, sand, etc and collect material in a open top drum for waste disposal Waste Disposal Method Material collected on absorbant materials must be disposed of in accordance with federal, provincial or local regulations regarding environmental controls -3­ PAINT CAN LABEL WATER REDUCIBLE ALKYD ENAMEL Color Finish High Gloss Calculated Coverage @ 1 Mil Thickness 726 sq ft/gal ( 14,8 sq m/litre) Application Air or Airless Spray Pot Life Not Applicable Dry Time Dry to Touch: 3 -4 hours @ 70°F (21 °C) with 50% humidity Dry for Use: 12 hours @ 70°F (21 °C) with 50% humidity Application Condition Apply only when air and surface temperatures are between 45 -100°F (7 -38°C) Application Procedure Apply in wet coat making even parallel passes Overlap each pass 50% to minimize bare areas or pin holes Recommended Thinning Distilled Water or Thinner Solution (P/N 6568648) Cleaning Equipment Thinner Solution (P/N 6568648l Refinishing Preparation Clean the surface of all dirt, loose paint, rust, oil and grease The surface must be deglazed or "scuff sanded" with 240-grit silicone carbide paper Sand only to remove " slick" finish Remove paint dust Flash Point Approximately 165°F (74°C) Extinguishing Media Dry chemicals, carbon dioxide, foam or "Class C" extinguishing equipment Shelf Life One year from manufacturing date when stored indoors DO NOT FREEZE Handling and Storage All containers must be tightly closed to avoid spilling while handling Material must be stored in a dry place and storage temperatures must be between 50°F ( 10°C) thru 104°F (40°C) Overexposure Effects Irritation to the nose, throat, lungs and eyes May also cause headaches and dizziness Respiratory Protection Material must be sprayed at a place equipped with exhaust system Proper air filtration mask (carbon cartridge) -air feed hoods must be used Ventilation (Type) Exhaust system Must have sufficient capacity, to keep solvent vapors below 20% of explosive limit of 25% volume of solvent vapor in air First Aid Procedure Eyes: Flush with large amounts of water for 15 minutes and get immediate medical attention Skin: Wash thoroughly w ith soap and water Inhalation: Breath fresh air and move away from area Spill or Leak Procedure Eliminate all ignition sources and clean up the area with rags, saw dust, sand, etc and collect material in a open top drum for waste disposal Waste Disposal Method Material collected on absorbant materials must be disposed of in accordance with federal, provincial or local regulations regarding environmental controls ALSO SEE GENERAL SERVICE BULLETIN #G -008 DATED 19 APRIL 84 FOR MORE DETAILED INFORMATION Anyone handling water reducible alkyd paints must be protected with coveralls, respirator, goggles and gloves Any exposed skin surface must be coated with protective skin cream, which later can be washed off with soap and water This paint is specified for Melroe machines Do not use on other surfaces exposed to children Failure to obey warnings can cause injury or death -4­ DATE: MODEL: SUBJECT: BOBCAT 19 April 1984 900, 1000 Series Clutch Disc (6593173) DIRECT TO: CB"' CB"' 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BT I Bulletin Installation Inst Manual Revision Clutch disc 1319265 is replaced by a new improved clutch disc, 6593173 When ordering a new clutch disc, specify part number 65931 73 The new clutch disc replaces the old disc in all applications Parts Fiche changes are being made The above is provided as product improvement information only, not a field modification Printed in USA BOBCAT FIELD MODIFICATION DATE: 	8 May 1984 MODEL: 	641 S/N 13001 Thru 13370 642 S/N 13001 Thru 14153 643 S/N 13001 Thru 13811 741 S/N 15001 Thru 15183 742 S/N 15001 Thru 15582 743 S/N 15001 Thru 17938 743DS S/N 50001 Thru 50146 SUBJECT: 	Hydraulic Tubeline Clamping DIRECT TO: I}!'"' I}!'"' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision The lift arm hydraulic cylinder tubelines (P/N 6564469 & 6564470) on the Bobcat loaders listed above must have an additional clamp installed Under certain conditions there are large amplitude vibrations of the steel tubelines between the hydraulic valve and the lift arm cylinder If unrestrained, these vibrations could cause failure of these tubelines Possible failures can be avoided by additional clamping of the tubelines to the frame This clamping must be done by a Bobcat dealer According to our records, the following serial numbered machine(s) were # shipped to your dealership These machines must have additional clamps installed as soon as possible We are sending the necessary parts so that you can complete the modification on these machines Melroe is notifying all the owners of the serial numbered machines listed of the requirement to have the clamps installed Please make arrangements with the owners to that the modification work can be completed on their machines If any of the loaders listed are no longer in your territory, please contact Peggy Belling at the Melroe Service Department, telephone number (701) 678-6484, and advise her of the name and location of the owner Melroe will give compensation for one ( 1) hour labor to complete the modification on each machine listed One additional hour is allowed for travel time for retailed machines Instructions are included on the reverse side of this letter evised 8 May 84 Printed in USA Installing Tubeline Clamp 1 	Lift the rear of the Bobcat and put jackstands under both rear axle housings 2 	 Remove the left rear wheel and tire assembly from the axle flange 3 	 Open the rear door and locate the two (2) tubelines to be clamped (Fig 1, Items 1 and 2) 4 	 Loosen the clamp which holds the tubelines that go to the left lift cylinder (Fig 1, Item 3) 5 	 Mark the location for the hole to be drilled in the left fender and drill a 41 inch (10,4 ·mm) hole (Fig 2) 6 	 Install the rubber strip between the tubelines and the fender (Fig 2, Item 4) 7 	 Install the bolt, clamp and nut (Fig 1, Items 5, 6, and 7) to hold the tubelines to the fender 8 	 Tighten the nuts to hold the clamps (Fig 1, Items 3 and 7) -2­ BOBCAT DATE: 10 May 1984 MODEL: 540 S/N 11999 & Below SUBJECT: Kit to Prevent Vapor Lock (6568275) DIRECT TO: CB" CB" CB" 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision A kit is available to help prevent vapor locking problems due to engine heat The kit will relocate the air cleaner, reroute fuel line, add a remote electric fuel pump and insulate the fuel tank The kit (p/n 6568275) can be ordered from Clark Central Parts, Chicago, IL The above kit is offered as a customer application option only No warranty consideration is given Printed in USA DIRECT TO: CB"' BOBCAT CB"' D  D D D D DATE: 15 May 1984 	Additional information about this subject is found in the following: MODEL: 900, 1ooo Series Service Bulletin        BTI Bulletin SUBJECT: Clutch Pressure Plate Assembly Installation Inst (6568499) Manual Revision The clutch pressure plate, part number 1319264, is replaced by kit part number 6568499 The kit consists of one pressure plate and six shoulder screws When ordering a new pressure plate, order kit number 6568499 Use the new shoulder screws in the kit when installing the pressure plate Do not reuse the old mounting screws  only Not a field modification Printed in USA BOBCAT DATE: 16 May 1984 MODEL: 641 -S/N 13209 Thru 13329 642 -S/N 13406 Thru 13988 643 -S/N 13524 Thru 13687 741 -S/N 15001 Thru 15155 742 -S/N 15001 Thru 15426 743 -S/N 15001 Thru 17140 743DS -S/N 50001 Thru 50121 SUBJECT: Hydrostatic Charge Relief Valve DIRECT TO: CB' CB' D D D D D Additional information about this subject is found in the following: Service Bulletin -c-=-,-----,-o---­ BTI Bulletin #154, #209 Installation Inst Manual Revision A low "buzzing" sound In the area of the hydrostatic pump assembly may be due to the charge relief valve becoming unstable at low hydrostatic flows (at idle) Although the noise due to the charge relief valve does not constitute a serious condition it may be objectional and a cause for complaint by some Bobcat owners In case of such complaint the valve parts should be removed for inspection (Figure 1, Item 1) The correct parts will be identical to those shown in figure 1 A-2701 A-2920 B-6948 PLUG POPPET P/N 6630784 P/N 6630786 Figure 1 -1-Printed in USA If the charge relief valve parts in the pump assembly are found to differ from those shown in Figure 1, new parts should be ordered from Clark Central Parts, using the part numbers specified Mel roe will give compensation for the cost of replacement parts plus one hour labor to install the parts This policy will apply only to those machines within the serial number ranges listed above -2­ BOBCAT FIELD MODIFICATION DATE: 5 June 1984 I MODEL: 1600 S/N 11099 & Below SUBJECT: Operator's Handbook Kit (6584796) and Service Decal (6585084) DIRECT TO: Li?' I I I I 1·1 rI 1-1 r J Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision Operator's Handbooks are now being installed on production 1600 loaders, beginning with loader serial number 11100 The service decal is also installed on these loaders The handbook and service decal must be installed on all 1600 loaders below service number 11100 The handbook fastened on the loader provides brief instructions available for every operator It is important for everyone that the operator is given the additional handbook instructions It will be especially important for you if asked as a dealer to be able to prove that the handbook instructions and warnings were provided as part of the operator's instructions According to our records, the following serial numbered loaders were shipped to your dealership and have not been retailed Please install the enclosed handbook kit and service decal on these units Printed in USA DIRECT TO: CB" BOBCAT CB" D  D D D D DATE: 18 June 1984 	Additional information about this subject is found in the following: MODEL: 743, 743DS, 1600 Service Bulletin        BTI Bulletin SUBJECT: Crankcase Drain Plug Installation Inst Manual Revision Crankcase drain plug 3974402 is replaced by plug 6630815 The new plug has a smaller hex (5/8") (16mm) making it easier to remove The new plug can be ordered from Clark Central Parts  only Not a field modification Printed in USA BOBCAT SAFETY NOTICE DATE: 27 June 1984 MODEL: 440 Serial Number 11513 & Below 443 Serial Number 11423 & Below SUBJECT: Hydraulic Control Linkage DIRECT TO: CB"' CB"' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision The hydraulic control linkage on the 440 series Bobcat loaders is being corrected to improve quality and function All prior built 440 series loaders (serial numbers listed above) must be updated with the revised parts The customers are being notified about this action by safety notice Your District w ill be assisting you in this program According to our records, the following model and serial number Bobcat loaders were shipped to your dealership Update kits are being shipped to your dealership to be installed on these machines Parts involved are: Kit #6593355 P /N Description Qty 6593352 Lock 2 (replaces 6564128) 6593353 Bellcrank 2 (replaces 6564126) 6630971 Cam follower 2 6563914 Washer 2 860-6 Nut 2 6563152 Washer, nylon 4 6598906 Bushing, nylon 8 6566977 Instruction, installation 1 Melroe will give compensation for 2 hours labor to complete the modification One additional hour is allowed for travel time for retailed machines BOBCAT DATE: 28 June 1984 MODEL: 443 S/N 11384 & Below SUBJECT: Fuel Filter Relocation DIRECT TO: [B" D D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision The fuel filter must be relocated to provided more clearance between the fuel line and the flywheel ring gear 1 	 Remove the mounting bracket (P/N 6564376) 2 	 Drill two (2), 406" (10,32 mm), holes 100" (25,4 mm) away from the original holes (Fig 1 ) 3 	 Install the bracket and filter, using the new holes (Fig 1) Melroe will give compensation for one (1) hour labor One (1) additional hour is allowed for travel time for retailed loaders Fig 1 Fuel Filter Mounting Bracket Printed in USA BOBCAT DATE: 2 July 1984 MODEL: 900, 1000 Series SUBJECT: Clutch Disc (6593173) DIRECT TO: CB"' CB"' D D D 0 D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision Clutch disc 1319265 is replaced by a new improved clutch disc, 6593173 When ordering a new clutch disc, specify part number 6593173 The new clutch disc replaces the old disc in all applications Parts Fiche changes are being made The above is provided as product improvement information only, not a field modification c BOBCAT FIELD MODIFICATION DATE: 12 July 1984 MODEL: 1600 S/N 11135 & Below ' SUBJECT: Servo Relief Valve DIRECT TO:, 111' fl?' 1 ! Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision The adapter (743108) for the servo relief valve has been replaced by an adjustable adapter (6585571 l on present production Model 1600 Loaders The new adapter provides for external setting of the servo and brake relief pressure All prior built Model 1600 Loaders must be updated with the revised part According to our records the following serial number Model 1600 Loader was shipped to your dealership The new adapter (6585571) and two shims (663021 7) are being sent to your dealership for installation on the loader Procedure to install the parts: 1 	 Remove the pressure tubeline (6585570) 2 	 Remove adapter (743108) poppet (6585438) spring (217685) and shim (6630217) from the port block Discard the adapter (743108) -1-	Printed in USA 3 	Install the parts in this order: (Figure 1) a 	 Spring (217685) b 	 2 Shims (6630217) c 	 Poppet (6585438) d 	 Adapter (6585571 ) w /0 -ring 4 	Be sure 0 -ring is installed on adapter Screw the jam nut all the way out on the fitting Turn the fitting all the way into the port block, then tighten the jam nut 6630217 Shim (2) Figure 1 5 	Connect tubeline (6585570) to the adapter 6 	Connect a pressure gauge to the "tee" fitting at the vane pump The servo pressure should be 250-260 PSI If the pressure is not correct, loosen the jam nut on the adapter (65855 71) at the port block Turn the adapter IN or OUT until the pressure is between 250-260 PSI Melroe will give compensation for one ( 1) hour labor to install the parts One ( 1) addition hour is allowed for travel time for retailed machines -2­ BOBCAT DATE: 11 July 1984 MODEL: 907, 909, 911 Backhoe SUBJECT: Bolt For Swing Pivot Pin (P/N 31C-1024) DIRECT TO: IB" IB" 0 0 0 0 0 0 Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision NOTE: 	This Service Letter replaces Service Letter same subject, dated 20 August 1981 The pivot pin for the swing frame is held in place by a 5/8" bolt at each end If the bolts are loose, remove them and use Loctite adhesive to cover the threads thoroughly before installing them Tighten the bolts to 180 -200 (244 -271 Nm) ft-lbs torque Printed in USA BOBCAT DATE: 24 July 1984 MODEL: 741, 742, 743, 743DS & 843 S/N 15001 & Above SUBJECT: Hydraulic Reservoir Overflow DIRECT TO: CW CW D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision Under certain operating conditions it is possible for hydraulic oil to transfer from the chain case to the hydraulic fluid reservoir, resulting in an overflowing reservoir It has been determined that this occurs when oil is forced from between the gears in the gearcase and impinges against the input shaft seal Some oil may get past the seal and join the motor case oil and, eventually, the hydraulic reservoir NOTE: 	Not all machines will have this problem This is not a field modification This condition can be remedied by installing seal, 651 5195, on the input shaft, next to the gear (Fig 1 ) To install the seal: 1 	 Remove the hydrostatic motor 2 	 Remove the old seal (6513588) and flat washer (6559619) 3 	 Install seal (651 5195) on the shaft 4 	 Check the flat washer It must be flat and smooth, with no burrs Install the washer 5 	 Install a new seal 6513588 Use seal tool MEL-1047 to properly install the seal 6 	 Re-install the motor  only No warranty is allowed Printed in USA Gearcase l Input 6559619 (Seal) (Washer) Figure 1 During the arrival condition inspection the torque of the axle housing bolts must be checked The nuts which hold the axle housing to the chaincase must be tightened to 325 ft-lbs (441 Nm) torque Be sure to follow the sequence shown below when tightening the nuts 10 6 4 A-­ 2 E-1103R B-7435 VIEW A-A , DATE: MODEL: SUBJECT: BOBCAT 26 July 1984 10808 Arrival Condition Inspection DIRECT TO: CB" CB" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision Printed in USA DIRECT TO: ffi"' BOBCAT ffi"' 0 0 0 0 0 DATE: 6 August 1984 	Additional information about this subject is found in the following: MODEL: 642, 742 Service Bulletin        B T I Bulletin SUBJECT: Exhaust Pipe Installation Inst Manual Revision A new improved exhaust pipe is now installed on present production Model 642 and 7 42 Bobcat Loaders The new exhaust pipe has reinforcement collars added to the flex ends to reduce breakage and increase service life The part number 6562988 remains the same The new exhaust pipe is available and can be ordered from Clark Central Parts Division The above is product improvement information only Not a field modification Printed in USA BOBCAT DATE: 7 August 1984 MODEL: 907, 909, 911 (Backhoes) SUBJECT: Husco Control Valve DIRECT TO: [B" [B" D D D D D ' Additional information about this subject is found in the following: Service Bulletin        B T I Bulletin Installation Inst Manual Revision Husco manufactured control valves are being installed on present production Melroe backhoes, beginning with serial numbers as follows: Model 907 909 911 Serial Number 1426 2037 0362 Attachment parts fiche to include parts information for the Husco valve is nearing completion and will be mailed to dealerships in the near future Printed in USA BOBCAT DATE: 15 August 1984 MODEL: 974, 975, 1080-B SUBJECT: Hydraulic Suction Hose (6592694) DIRECT TO: CB' CW D 0 0 D 0 Additional information about this subject is found in the following: Service Bulletin        B T I Bulletin Installation Inst Manual Revision Hydraulic suction hoses of an incorrect specification were installed on some 974, 975 and 1080-B Bobcats built in 1984 The hose is not compatible with hydraulic oil Failure symptoms are softening (spongy) hose after a short period of time with eventual complete deterioration of the hose According to our records the following model and serial number loader(s) was shipped to your dealership: We are sending you the correct hose Please install the correct hose on the loader(s) listed above It is important that this be done as soon as possible Hydraulic suction hose failure could result in serious damage to the hydrostatic system and costly repairs Loaders already retailed should be corrected first to minimize customer down time Melroe will give compensation for one hour labor to install the correct hose One additional hour (two hours for Feller Buncher) is allowed for travel time for retailed loaders Printed in US A lllELROECOMPANY GENERAL ---SERVICE BULLETIN iiiiiiiiiiiiiii AFFECTING: Product BOBCAT LOADERS AND BACKHOES 440, 540, 640, 740, 843, 1600 AND 2000 SERIES; Model 907, 909, 911 BACKHOES Serial No SEE BELOW Manual No SUBJECT: POLYURETHANE PAINT FOR TOUCH-UP AND REFINISHING Additional information about this subject is found in the following: The following Serial Numbered Bobcat Loaders are painted with polyurethane paint Model Serial Number Model Serial Number Service Letter BTI Bulletin Installation Instr Manual Revision 440 741 5017-M-15159 & Above 443 742 5018-M-15523 & Above 540 501 O-M-13092 & Above 743 5019-M-17417 & Above 543 5024-M-13156 & Above 743 DS 5025-M-50137 & Above 641 5013-M-13336 & Above 843 5026-M-1 5909 & Above 642 5014-M-1 4067 & Above 1600 643 5015-M-13733 & Above 2000 Polyurethane paint has a finish that is more scratch resistant and presents a more durable finish with a longer-lasting gloss than other paints SURFACE PREPARATIONS Touch-Up Because of the slick finish of polyurethane paint, scratches and chips cannot be touched-up in the usual manner In most cases the entire surface must be lightly sanded in all directions from the scratch or chip to some break point on the Bobcat loader (Fig 1 ) The edges of the scratch or chip must be feathered and, if the damage is deep, fillers must be used to level the surface at the point of damage Do not grind the paint down to bare metal Use a 240-grit silicone carbide paper for sanding, and remove all sanding dust before applying wet paint Refinishing About two weeks after the original application of polyurethane paint, it will have increased in hardness to a point where the surface cannot be recoated without preparation to insure adhesion of the new coat To prepare hardened polyurethane paint, the entire surface must first be deglazed or "scuff sanded" with 240-grit silicone carbide paper Sand only enough to remove the scratches and the slick finish Avoid grinding down to bare metal unless rust is present Any bare metal will require at least two coats of paint Remove all sanding dust with a solvent-moistened rag Bobcat loaders which have paint other than polyurethane, can also be refinished using polyurethane paint Use the same deglazing and sanding procedure as for polyurethane paint above No primer is needed Printed in USA As with any paint, the surface to be painted with polyurethane paint must be thoroughly cleaned of all dirt, rust, loose paint, oil and grease See "SURFACE PREPARATIONS" for the correct procedure Polyurethane paint can be applied by using either the air or airless atomization spray equipment Thinner can be added to the paint as follows: For Airless Spray -up to 10% of total volume For Air Spray -up to 20% of total volume It is important to clean the spray equipment immediately after use to prevent hardening of the paint Use thinner/cleaner solution (See P/N Below) Temperature and humidity can effect the drying time of the paint The ideal conditions are: Dry to Touch 3/4 to 1-1/2 hours@ 70°F (21°C) with 50% Relative Humidity Dry for Use 12 hours @ 70°F (21°C) with 50% Relative Humidity Polyurethane paint comes in two (2) parts (3 to 1 ratio) which must be mixed together before application The quantity shown below is the total quantity of the two (2) parts after they are mixed Smaller amounts can be mixed at a ratio of 3 to 1 PAINT FACILITIES AND PERSONAL PROTECTION Use a paint booth which conforms to regulations applicable in your area The protection required is that all exposed skin areas must be protected with skin cream Gloves may be used to protect the hands Goggles must be used to protect the eyes The requirement for respirators and possible complete head coverings are covered by regulations applicable in your area It is very important that people, in and around the area where any paint is being used, be protected for their own health as well as for compliance with regulations GENERAL When welding on the surfaces where the paint is affected by the heat, there will be some gases released which may be toxic This is true of any paint, including polyurethane, so it is recommended that a respirator be worn by the welder if there is to be any welding done under these conditions When grinding polyurethane or other paints, it is recommended that respirators be worn to prevent inhalation of the paint dust Polyurethane paint has a flash point of approximately 72°F (22°C) This means that the vapors produced at this temperature will ignite if exposed to a spark or open flame Part Number Color Quantity* * Polyurethane paint comes in two (2) parts (3 to 1 ratio) which must 6568746 6568745 White White 1 Liter Kit 4 Liter Kit be mixed together before application The quantity shown is the total quantity of the two (2) parts after they are mixed 6568750 6568749 6568754 Orange Orange Grey 1 Liter Kit 4 Liter Kit 1 Liter Kit Prices are available upon request Order paint from Clark Central Parts Division 6568753 Grey 4 Liter Kit 6568758 Yellow 1 Liter Kit 6568757 Yellow 4 Liter Kit 6568759 Thinner & Cleaner 4 Liter BOBCAT FIELD MODIFICATION DATE: MODEL: SUBJECT: 27 August 1984 909 -S/N 1931 & Above; 911 -S/N 0335 & Above Bucket Link, P/N 6592874 (Cast Type) DIRECT TO: Ut' IB"" n I I II Ii II Additional information about this subject is found in the following: Service Bulletin       BTI Bulletin Installation Inst Manual Revision The bucket link, 6592874, is incorrectly installed on some Model 909 and 911 Backhoes The serial number backhoes listed above must be inspected and, if necessary, corrected to prevent damage to the bucket link The link, when correctly installed, will appear as shown in figure 1 The side with the two ribs close together must face up from the dipperstick If the side with the two ribs far apart is facing up, remove the link and turn it over so that the two close together ribs are up Figure 1 B-7453 Melroe Company will give compensation for 1 hour labor to make the correction on backhoes which have the link incorrectly installed One additional hour is allowed for travel time for retailed backhoes Printed in USA BOBCAT FIELD MODIFICATION DATE: 21 September 1984 MODEL: 974, 975, 1080-B SUBJECT: Hydraulic Suction Hose From Melroe Company Parts Sales DIRECT TO: ffi""' ffi""' 0 0 ··­ ·- [] [J o Additional information abot this subject is found in the folloing: ! Service Bulletin      BTI Bulletin ·----­ Installation Inst Manual Revision According to our records your dealership was shipped hydraulic suction hose, part number 6592694, from Melroe Company Parts Sales in Chicago, between 1 January 1984 and 31 July 1984 It has been determined that the hose you received is probably made of defective material not compatible with hydraulic fluid Therefore, we ask that you please reorder a new hose from Melroe Company Parts Sales in Chicago The correct hose is now in stock Submit a warranty claim for the old hose to Melroe Company Service Department in Gwinner Hold old hose for receipt of approved warranty claim form Additional instructions will be attached to the approved form Printed in US A DIRECT TO: [fr' BOBCAT ftr I I I f I FIELD MODIFICATION I DATE: 30 September 1984 MODEL: 1080-B (S/N Listed Below) SUBJECT: New Clutch Assembly (Rockford) for Non-Retailed Machines Additional information about this subject is found in the foll1wing: Service Bulletin         BTI Bulletin Installation Inst Manual Revision er: The clutch pressure plate and disc have been replaced on present production 1080-8 Feller Bunchers to improve the service life of the clutch system This change become effective on machine serial number 12111 New parts are as follows: Part Number Description Replaces P/N 6593395 Clutch Disc 6593173 6568977 Pressure Plate Kit 6568499 6593394 (Includes) Pressure Plate (1 ) (1319264) 6593093 Bolts (6) (6593093) Unchanged According to our records the following machines were shipped to your dealership and have not been retailed All 1080-8 Feller Bunchers which have not yet been retailed must he updated with the new clutch system The new clutch parts are being shipped to your dealership to be installed on the serial number machine(s) listed above Please have this done before the unit is retailed Submit a warranty claim and hold the old clutch parts for return authorization from Melroe Company, Service Department, Gwinner ND 58040  for 10 hours labor to install the new clutch parts Printed in USA DIRECT TO: !11"" BOBCAT !Pi"" ii-( FIELD MODIFICATION DATE: 2 October 1984 	Additional information abo t this subject is found in the foll wing: MODEL: 1080-B (S/N12001Through12110l Service Bulletin      BT I Bulletin SUBJECT: New Clutch Assembly (Rockford) for Installation Inst Retailed Machines Manual Revision - The clutch disc and pressure plate have been replaced on present production 1080-B Feller Bunchers to improve the service life of the clutch system New parts are as follows: Part Number Description 	Replaces P/N 6593395 Clutch Disc 6593173 6568977 Pressure Plate Kit 6568499 6593394 (Includes) Pressure Plate ( 1) (1319264) 6593093 Bolts (6) (6593093) Unchanged According to our records the following machines were shipped to your dealership and have already been retailed All retailed 1080-8 Feller Bunchers must be updated with the new clutch system when the old clutch system fails The new clutch parts are being shipped to your dealership to be held in stock until failure occurs on the serial number machine(s) listed above Submit a warranty claim and hold the failed parts for return authorization from Melroe Company, Service Department, Gwinner ND 58040  for 10 hours labor to install the new clutch parts Two hours labor is allowed for travel time Printed in U S A DIRECT TO: [tY BOBCAT Ctr"' , , 1·1 SAFETY NOTICE r1 Additional information about this DATE: 4 October 1984 subject is found in the following: MODEL: 440 SIN 11565 & Below Service Bulletin       443 SIN 11509 & Below BTI Bulletin Installation Inst SUBJECT: Safety Latch Pin For Cab Manual Revision A heavier safety latch pin (for locking the operator cab when it is in the raised position) is being installed on present production 440 series Bobcat Loaders Latch pin 6593389 replaces latch pin 6544995 Spring 6593390 replaces spring 6563149 All prior built model 440 and 443 loaders (serial numbers listed above must have the old latch pin and spring replaced by the new pin and spring According to our records the following model and serial number loaders were shipped to your dealership For each affected loader a modification kit, 6593391, is being shipped to your dealership for installation Please complete this modification immediately Melroe Company will give compensation for 1 hour labor to install the parts on each affected loader One additional hour is allowed for travel time for retailed machines · Printed in USA BOBCAT FIELD MODIFICATION DATE: 13 November 1984 MODEL: 2000 Articulated Bobcat (S/N 13071 & Below) SUBJECT: Operator's Handbook Kit (6584472) DIRECT TO: [B"' [B"' [B"' 0 0 0 D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin Installation Inst Manual Revision ('­ i \ Operator's Handbooks are now being installed on production 2000 loaders, beginning with loader serial number 13072 The handbook, kit number 6584472, must be installed on all Model 2000 loaders below serial number 13072 The handbook fastened on the loader provides brief instructions available for every operator It is important for everyone that the operator is given the additional handbook instructions It will be especially important for you, if asked as a dealer, to be able to prove that the handbook instructions and warnings were provided as part of the operator's instructions According to our records, the following serial numbered loaders were shipped to your dealership and have not been retailed Handbooks are being mailed to all owner's of retailed loaders, with instructions for the owner to install them Melroe Company will give compensation for 1 /2 hour labor to install the handbook on affected machines Printed in USA f' ,/ \ DIRECT TO: IB"" BOBCAT IB"" IB""  D D FIELD MODIFICATION D D DATE: 14 November 1984 	Additional information about this subject is found in the following: MODEL: 2000 Service Bulletin        BTI BulletinSUBJECT: Operator's Handbook Kit (6584472) Installation Inst Manual Revision       Operator's Handbooks are now being installed on production 2000 loaders, beginning with loader serial number 13072 The handbook, kit number 6584472, must be installed on all Model 2000 loaders below serial number 13072 The handbook fastened on the loader provides brief instructions available for every operator It is important for everyone that the operator is given the additional handbook instructions It will be especially important for you, if asked as a dealer, to be able to prove that the handbook instructions and warnings were provided as part of the operator's instructions Handbooks are being mailed to dealers who have earlier built machines in their inventory Mel roe Company will give compensation for 1/2 hour labor to install the handbook on affected machines Additional handbook kits (6584472) can be obtained from Melroe Company Parts Department Printed in USA ,, /, i \ DIRECT TO: ar" BOBCAT ar" 0 CJ 'I '-' 0 n LJ FIELD MODIFICATION DATE: 15 November 1984 MODEL: Model 2500 Hydraulic Breaker SUBJECT: Mounting Frame Reinforcement (Bob-Tach Mount) Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision The mounting frame (6567796) now has additional reinforcement in the area shown The rectangular plate has been replaced by a longer plate to give better support (Figure 1 ) Failure may occur in the area of the rectangular plate (Figure 1 ) If this happens the frame can be repaired by installing new plate, part number 6568969 The new plate can be ordered from Melroe Parts Marketing, Chicago, IL To 	repair a mounting frame: 1 	 Remove the breaker assembly from the Bob-Tach 2 	 Tip the breaker assembly so that point is up (See Figures 1 & 2) 3 	 Use a torch to remove the rectangular plate (Figure 1) 4 	 Weld the new plate, 6568969, in position as shown NOTE: Be sure that the access hole for the point retaining pin is located as shown (Figure 2) Put a 25" fillet weld on each side of the mounting frame Weld the bottom edge of the plate 5 	 Weld any cracks which may be present in other areas of the frame Printed in USA Fig 1 Fig 2 Melroe Company will give compensation for the cost of the plate and two hours labor to complete the repair job One additional hour is allowed for travel time for retailed units ( '-/ DIRECT TO: l:H' BOBCAT IY D D D D D DATE: 28 November 1984 	Additional information about this subject is found in the following: MODEL: See Below Service Bulletin        SUBJECT: Gearbox Input Shaft -P/N 6558271 BTI Bulletin         (843); 6558272 (740's) Installation Inst Manual Revision 741 -S/N 19999 & Below; 742 -S/N 20009 & Below; 743 -S/N 20189 & Below; 743DS -S/N 50999 & Below; 843 -S/N 20051 & Below Some loaders (See Serial Numbers above) may have gearbox input shafts which are too long If the shaft protrusion (Figure 1) is more than 476" (12,09 mm), it may interfere with the motor housing This can result in galling of the geroler parts I Figure 1 If motor failure occurs, check the shaft protrusion per figure 1 when making repairs The shaft protrusion must be measured from the motor mounting face on the gear box to the end of the shaft If the shaft length is more than 476" (12,09 mm) the shaft must be shortened by grinding NOTE: 	This is not the only cause for motor galling, so be sure to check dimensions carefully  for labor costs per Service Policy & Procedure Manual Printed in USA Two changes have been made to the Melroe built control valve, as follows: 1 	 Auxiliary hydraulic detent sleeve, 6592095, has been changed to part number 6593349 The new detent sleeve has a steeper ramp angle to give greater holding force when the spool is placed into detent 2 	 Bushing, 6592103, is eliminated This bushing was used as a retainer for the 0-ring at each end of the spool The bore recess has been removed and an 0-ring groove made for the spool 0-rings The 0-rings BOBCAT DATE: 29 November 1984 MODEL: 440 thru 843 (Series) 1600, 2000 SUBJECT: Control Valve (Melroe) are 	not changed (Figures 1 & 2)  llll llll     11 Bushing / 0-R;ng Bushing (6592103) 	(25K-30020) (6592103) figure 1 -Valve with Bushing (Non-Current) DIRECT TO: cH"" cH"" D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision     11     11 -· 0-Ring (25K-300201 Figure 2 -Valve without Bushing (Current Production)  only NOT a field modification :; BOBCAT DATE: 30 November 1984 MODEL: 1080-B SUBJECT: Rockford Clutch Installation DIRECT TO: rn""' rn""' D D D D D Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision When installing the Rockford clutch system, certain steps must be taken to insure correct operation: 1 	 The new pressure plate assembly uses a different set of mounting holes which are provided on the flywheel NOTE: Early built John Deere engines (prior to August 1978) has only one set of holes If the Rockford clutch is being installed on an early built engine it will be necessary to install a new flywheel 2 	 Install the clutch disc with springs toward pressure plate side (away from flywheel) 3 	 The three metal clips must be removed after the pressure plate is secured with the mounting bolts (Figure 1) 4 	 Tighten the shoulder (mounting) bolts to 25-28 ft-lbs (34-37 Nm) torque 5 	 Check the clutch release pedal and adjust as required to allow clutch to be disengaged when the pedal is pushed - DIRECT TO: Clr" BOBCAT Clr" D D D D D DATE: 3 December 1984 	Additional information about this subject is found in the following: MODEL: 843, 2000 (Perkins 4154) Service Bulletin        BTI Bulletin         SUBJECT: Cylinder Head & Gasket Installation Inst Manual Revision The previous 4154 engine (6563111) and present 4154 (200 series) engine (6564576) both use the same cylinder head gasket, part number 998057 The water passages on the face of each cylinder head are designed differently, to assure proper flow of the water circulation in the head Special Note: The cylinder head (997935) will fit on a 4154 200 series engine, but is not recommended or approved for use on that engine Caution: Running engine without a thermostat is not recommended or approved By not having a thermostat the engine does not achieve proper operating temperature and sludging of the oil could occur Printed in USA DIRECT TO: cY BOBCAT cY 0 0 0 FIELD MODIFICATION 0 0 DATE: 4 December 1984 MODEL: 640, 740 (Series) SUBJECT: Clamping of Hydraulic Tubelines Additional information about this subject is found in the following: Service Bulletin        BTI Bulletin         Installation Inst Manual Revision In May, 1984 your dealership was notified of the serial numbers for model 640 and 740 series loaders which must have an additional lift arm tubeline clamp to avoid a possible failure from excessive vibrations of the tubelines You received the necessary parts and the attached dated 8 May 84 so you could clamp the tubelines The owners of these identified loaders were notified about the correction by a letter dated 27 April 1984 According to our records, you have not corrected all of the identified loaders in your territory You are reminded that this field modification should be done promptly to avoid possible tubeline failures Melroe Company has provided you with parts, instructions and dealer compensation with the expectation that you can fix these tubelines Your Melroe District should be told if there is any machine identified in the dated 8 May 84 which you cannot fix The Warranty Compensation authorized in the dated 8 May 84 is still in effect WARNING: Hydraulic tubelines of loaders identified for owners on 27 April 1984 need field modification immediately The modification must be done by a Bobcat dealer according to Dealer dated 8 May 84 Tubelines without this modification can fail from excessive vibration Failure of certain tubelines can allow uncontrolled falling of the lift arms which can cause injury or death Printed in USA DIRECT TO: or" BOBCAT or" 0 0 0 0 FIELD MODIFICATION o DATE: 20 December 1984 	Additional information about this subject is found in the following: MODEL: 642, 742 Service Bulletin        BTI Bulletin         SUBJECT: Fuel Hose Lines Installation Inst Manual Revision Some recently built model 642 and 742 Bobcats might have incorrect fuel hose lines installed The incorrect hoses are not compatible for use with gasoline fuel According to our records the following model and serial number Bobcat loader was shipped to your dealership: Please inspect the fuel hose lines on the loader for correct specification If the hose is identified as Gates, has a swollen appearance and feels " spongy" it must be replaced immediately The correct hose is firm and has a "textured" appearance A length of the correct hose is being shipped to affected dealers for use on loaders which need the correct hose Melroe will give compensation for one hour labor to replace the fuel hose(s) on serial numbered loaders listed which have incorrect hoses installed One additional hour is allowed for travel time for retailed machines Printed in USA Melroe Division bobcat GENERAL SERVICE BULLETIN AFFECTING: Product Model BOBCAT LOADER 540s, 640s, 740s, 843 and 2000 Serial No Manual 	No SUBJECT: LATCH PIN FOR REAR DOOR PROBLEM: Latch pin failure CAUSE: 	The pin is not strong enough CORRECTION: 	Install new latch pin (P/N 6599361) (Fig 1, Item 1 ) Order parts from Clark Equipment Co, Central Parts Divi­sion, 7300 S Cicero, Chicago, IL 60629 NOTE: 	If the new pin does not fit tight in the adjustment bolt (Fig 1, Item 2), replace the adjustment bolt (P/N 6564525) POLICY: 	Melroe will give warranty compensation per the War­ranty Policy and Procedure Manual for loaders within the warranty period I -­ ti ,, I/ · ( I I I I I I I I Q L-------, ----QI E-1326 Fig 1 Latch Mechanism for Rear Door c \ :::> c ;/ 7 c -, c 1 j ' ---	e - 0 0 IL -	\I Printed in USA - *bobcat GENERAL SERVICE BULLETIN AFFECTING: Product ALL BOBCAT LOADERS AND ATTACHMENTS Model Serial No Manual No SUBJECT: KEEPING HYDRAULIC OIL CLEAN All Bobcats have hydraulic oil filters to keep the oil clean while you are using the loader It is also important to keep the hydraulic oil clean while it is in storage and when you are putting it into a machine Below is a list of procedures that you can use to help prevent contamination of the hydraulic oil  	 Store the oil in a clean, dry place  	 Put drums of oil on the side and put a cover over them to prevent accumulation of dust  	 To avoid condensation, store the drums in an area that does not have sudden temperature changes, and keep the drums full  	 Wipe the area around the plug before you open it to prevent dirt from falling into the oil  	 If dirt gets into the oil, make sure you clean the oil before using it  	 Large particles can be removed with a 100 mesh screen  	 Let the drum set for a period of time and then use only the clean oil from the top of the container  	 Use a pump/filter system to put oil into the machine (Use either a 1 0 micron or a 3 micron absolute filter)  	 Use a clean container with a cover to carry the oil from the storage drum to the machine  	 Before you remove the filler cap, clean the filler cap and the area around it with a lint-free cloth  	 Install the filler cap immediately after filling Following these simple procedures can prevent contamination of your hydraulic system Your loader will stay on the job longer and unnecessary repairs will be prevented G-004 Bulletin Number 20 OCTOBER 81 Date Additional information about this subject is found in the following: Service Letter           BTI Bulletin          Installation Inst          Manual Revision        CURK:= bobcat GENERAL SERVICE BULLETIN AFFECTING: BACKHOE Product 910 Model 6553561-MA-196, and Above Serial No Manual No SUBJECT: DIPPERSTICK CYLINDER FAILURE The cylinder is identified by a tag at the end of the case and by the length of the case 26" (660 mm) long PROBLEM: Cylinder rod bending and breaking CAUSE: (1) The cylinder case is too short 26" (660 mm) long (2) The port relief valve in the control valve is 3000 PSI CORRECTION: Order cylinder spacer and relief valve kit (P/N 6562044) from Clark Central Parts in Chicago Remove the 3000 PSI port relief valve at the lower end of the dipperstick control valve section Install the 2750 PSI port relief valve from kit Disassemble the dipperstick cylinder and install the spacer on the cylinder rod behind the piston (Fig 1) POLICY: Melroe will give warranty compensation for the cost of the kit and 2 hours labor ---:::·-:: t I EXPIRATION DATE: November 30 1980 Nut G-003 Bulletin Number 4 MARCH 80 Date  D D B-3534 Fig 1 Cylinder Spacer Refer To Bulletin No(s) Printed in USA BULLETIN STATUS NON CURRENT D CLqRK:= G-001 Bulletin Number 31 JULY 79 Date GENERAL bobcat SERVICE BULLETIN AFFECTING: BACKHOE · Product 908A Model Serial No  D D Manual No SUBJECT: MORE SUPPORT FOR BACKHOE CONTROL PANEL: PROBLEM The control panel of the Backhoe comes into contact with the cross-member of the Bobcat lift arm or the support area of the tilt cylinder CAUSE Not enough support for the Backhoe control panel CORRECTION Install kit number 6561235, which has two braces (Fig 1) for the control valve support bracket Kit can be ordered from Chicago Central Parts POLICY Melroe will give warranty compensation for parts and 1 hour labor EXPIRATION DATE 30 June 1980 Refer To Printed in USA D Bulletin NoIsl CLqRK=: GENERAL bobcat SERVICE BULLETIN AFFECTING: BACKHOE Product Model 908A Serial No Manual No SUBJECT: 908A BACKHOE CYLINDER HOSES PROBLEM: Hydraulic hose damage r-- 	CAUSE: The hose location is not correct when the backhoe is operated CORRECTION: Remove the existing clamps holding the hydraulic hoses in location The hydraulic hoses must be put in location as shown in figure 1 & 2 Install clamps as shown POLICY: compensation for parts or labor Printed in USA Refer To Bulletin NoIsl