GEAR-DRIVE 1T1979 - 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 must be administered as soon as possible. When reporting the repair, use "PI3881" as the Part Number, "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description Code. Exception: If the repair is done after failure, use "PI3881" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.
Completion Date
November 30, 1996Termination Date
May 31, 1997Problem
The 1248474 Transformer Assembly used on medium voltage SR4B Generators may cause a loss of sensing voltage as a result of insulation deterioration between the primary coil leads and the coil face.
Affected Product
Model & Identification Number
3508 (23Z6192, 23Z6295)
3512 (8RM107 24Z6512 , 24Z6518, 24Z6566, 24Z6598, 24Z6599, 24Z6600, 24Z6618, 24Z6622 , 24Z6624, 24Z6641, 24Z6652, 24Z6744, 24Z6745, 24Z6749, 24Z6891 , 24Z6906, 24Z6985, 24Z6988, 24Z6996)
3516 (25Z4584, 25Z4589, 25Z4591, 25Z4604, 25Z4644, 25Z4658, 25Z4735, 25Z4738 , 25Z4742, 25Z4773, 25Z4793, 25Z4794, 25Z4797, 25Z4798, 25Z4802 , 25Z4889, 25Z4918, 25Z4928, 25Z4931, 25Z4967, 25Z4979 7RN198 , 7RN245, 7RN254-260, 7RN288-290 5SJ313-315 , 5SJ320, 5SJ362, 5SJ368, 5SJ369, 5SJ372, 5SJ385, 5SJ386, 5SJ410, 5SJ422-426 , 5SJ428, 5SJ429 4XF590 , 4XF592, 4XF608-611, 4XF613, 4XF614 4EK494 , 4EK671, 4EK672, 4EK698)
GENERATORS (2FN556 8NN501 )
Parts Needed
2 - 1365057 Transformer AssemblyAction Required
Parts Stock
Remove all 1248474 Transformers from Parts Stock.
Affected Product
Replace the 1248474 Isolation Transformer with the 1365057 Isolation Transformer. There are two transformers on each generator and are located inside the terminal box.
Owner Notification
U.S. and Canadian owners will receive the attached Owner Notification.
Service Claim Allowances
Parts Stock
Submit one claim for all 1248474 Transformers removed from Parts Stock.
Affected Product
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.
Attach.(1-Owner Notification)Copy Of Owner Notification For U.S. And Canadian Owners