Product Support Program For Reworking The Bucket Kickout And Positioner Group On Certain 416B, 426B, 428B, 436B, And 438B Backhoe Loaders Caterpillar

NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

NOTE: This Program can be administered either before or after a failure. In either case the decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS8063" as the Part Number and "7755" as the Group Number. If administered before failure, use "56" as the Warranty Claim Description Code and use "T" as the SIMS Description Code. If administered after failure, use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.

NOTE: This Revised Service Letter replaces the February 7, 1994 (Revised September 1994) Service Letter. A change was made to the TERMINATION DATE.

Termination Date

Problem

The 9R7639 Kickout and Positioner Group may fail due to binding pivot points in the linkage system of certain 416B, 426B, 428B, 436B, and 438B Backhoe Loaders.

Affected Product
Model & Identification Number

416B (8SG1-4168 8ZK1-849 )

426B (5YJ1-1053)

428B (7EJ1-1966)

436B (6MJ1-483)

438B (3KK1-891)

Parts Needed

1 3B8489 Fitting (use as required)

1 9R0139 Bearing

1 9R0614 Bearing

2 9R4331 Spacer

1 9R9132 Link Assembly

1 8T4121 Washer

1 396315 Clevis Pin

1 1021649 Pipe Assembly (use as required)

1 1146673 Damper Assembly

1 1124498 Boss

1 1129510 Pivot

1 1129511 Lever Assembly

1 1129513 Spacer

Action Required

See attached rework procedure.

Service Claim Allowances

NOTE: This is a 8-hour job.

Parts Disposition

Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.

Attach.

(1-Rework Procedure)

Rework Procedure

Frame

1. Remove both 9R0139 Bearings from the right hand loader tower pin.

2. Install a new 9R0614 Bearing and a new 9R0139 Bearing.

NOTE: The 9R0139 Bearing (the longer of the two bearings) should be installed in the outside position on the tower and pressed in flush with tower cross tube.

Illustration 1

Lift Arm

Weld a new 1124498 Boss to the inboard surface of the right hand lift arm as shown in Illustration 2.

Illustration 2

Hydraulic Hand Control

1. Rework the 9R7782 Bracket as shown in Illustration 3.

Illustration 3

2. Remove the existing 1036276 Control Rod (control lever bracket to loader valve). Refer to Illustration 4.

3. Measure the length of the control rod.

4. Adjust the length of a new 1146673 Damper Assembly to the measured length of control rod.

5. Install the adjusted 1146673 Damper Assembly in place of control rod.

NOTE: Place a new 8T4121 Washer between the ball joint and the bracket).

Illustration 4

Bucket Kickout And Positioner Group

1. Remove the existing 9R9134 or 1021645 Pivot and 9R9143 Lever Assembly as shown in Illustration 5.

2. Install a new 1129511 Lever Assembly in place of the 9R9143 Lever Assembly.

3. Install 1129510 Pivot and 1129513 Spacer in place of existing 1021645 Pivot.

4. Remove existing 9R9132 Link Assembly and replace it with a new plated 9R9132 Link Assembly.

NOTE: Install the existing 9R4331 and 9R5238 Spacers between the pivot and loader arm.

Illustration 5

3. Measure the distance between the centerlines of the pin bores of the 1021649 Pipe Assembly. Refer to Illustration 6. If the measurement is 2008 ± 3 mm, reuse the existing rod.

Illustration 6

NOTE: If the pipe is reused, add a 3B8489 Grease Fitting to the bucket link end of the pipe assembly as shown in Illustration 7. Reuse the existing clevis pin and install it so the split pin is to inside of tractor.

Illustration 7

4. If the existing pipe assembly does not meet the specification in Illustration 6, install a new 1021649 Pipe Assembly.

NOTE: If a new 1021649 Pipe Assembly is used, be sure it has a grease fitting installed as shown in Illustration 7. Use the existing clevis pin and install it so the split pin is to inside of the tractor. Install additional 9R4331 Spacers as necessary to ensure a 3 mm maximum clearance exists on each side of tractor between the lift arms and the wear bars on the radiator guard. Connect the new 1021649 Pipe Assembly to the pivot with a new 396315 Clevis Pin.

5. Adjust the bucket angle to 53 ± 2 degrees. Follow procedures in the Service Manual.