COVER 7C0725 - Caterpillar

Caterpillar: Confidential Yellow
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 only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS0591" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.
Although this Program is to be administered as described above, it can can also be administered before a failure occurs if the valve cover is removed for any other repair or maintenance. If administered before failure, use "56" as the Warranty Claim Description Code and use "T" as the SIMS Description Code.
This repair requires the use of a 9U5300 Unit Injector Spring Compressor Group. Be sure to have this service tool on hand prior to scheduling any repairs.
Termination Date
November 31, 1992Problem
The fuel injector clips may fail on certain 3176 Truck Engines which had injectors replaced after January 1, 1991. A new 6I2538 Clip, made from higher strength material, can be installed to increase the reliability and service life of the injector.
Affected Products
Model & Identification Number
The following 3176 Truck Engines if not previously reworked and stamped with "3X" next to Serial No. Plate.
3176 (2YG1-Up)
Parts Needed
Quantity per injector replaced after January 1, 1991
1 - 6I2538 Clip Add injector(s) and related seal(s) if clip is broken in more than three pieces. Add 336044 O- Ring Seal if thrust pad o-ring is damaged.
Action Required
1. Only certain date code injectors installed as field replacements after January 1, 1991 require c-clip replacement.To determine if any c-clips need reworking requires inspection of the block next to the serial plate, the top surface of the injector spring retainer, and the injector date code.
2. Check for "3X" stamped on the block next to the serial number plate. If the block has been stamped, do not proceed with the rework.3. Inspect the top surface of the injector spring retainer for a red or yellow stripe. The red or yellow indicates that the injector has the latest c-clip and that particular injector requires no further action. Engines equipped with a Jake Brake may require removal of the brake to see the top of the injector clearly.4. Injectors without red or yellow stripes require inspection of the identification label on each fuel injector. The labels can be seen just above the top surface of the valve cover base on the right side of the engine. Record the part number and date code of each injector. Refer to Illustration for the location of the part number and date code on the label. 5. Any injectors without red or yellow stripes that have the following date codes require the c-clips to be reworked.LH, MH, AJ, BJ, CJ, DJ, EJ, or FJ
It may not be possible on many