BEARING-IDLER 1859159 - Caterpillar

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.
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 "PS8715" 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.
Termination Date
August 31, 1997Problem
The 9X7876 Coil Assemblies on the solenoids of the 6Y7824 Control Valve Group on the transmissions of certain 12H, 120H, 135H, 140H, 143H, 160H and 163H Motor Graders may short out due to water entry.
Affected Product
Model & Identification Number
12H (4XM1-744, 4XM746 2LR1-290 8MN421 , 8MN423 2WR1-460 )
120H (4MK1-146 2AN1-55 , 2AN57 9FN338-361 5FM338 , 5FM345, 5FM347-349 6NM1-245 3GR1-34 )
135H (3YK1-92 8WM235-237 )
140H (2ZK1-818, 2ZK820-825, 2ZK827-830, 2ZK832-836, 2ZK852 5HM258-311 , 5HM313-321, 5HM324 8KM1-382 9ZN1-87 9TN58-66 3FR1-46 )
143H (1AL1-141)
160H (9EJ1-278 2FM338 , 2FM339 6WM1-336 )
163H (5AK1-72)
Parts Needed
8 - 1359977 Coil As.Action Required
See the attached procedure.
Service Claim Allowances
This is a 2-hour job.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
Attach.(1-Rework Procedure)Rework Procedure
1. Remove the three 6V4248 Bolts and 8T4121 Washers that fasten the transmission control valve guard (8E7107 Plate Assembly and 1137745 Plate Assembly) to the transmission case.2. Unplug and remove the existing 9X7876 Coil Assemblies from each solenoid valve by removing the retaining nut.3. Install a new 1359977 Coil on each solenoid valve. To avoid confusion, replace only one coil assembly at a time. This will help prevent the wires from be mixed. When installing the new coils, rotate them so that their wire leads point down as much as possible. This will help the water drain from the coils instead of into the coils.
4. Finish installing each new coil by installing the retaining nut and tightening it to a torque of 20.0 2.5 N M (15 2 LB. FT.). Over tightening may damage the coil assembly.
5. Install the transmission control guard back onto the transmission case.6. Test the machine for proper transmission operation.