COVER AS 2095502 - Caterpillar

Caterpillar: Confidential Yellow
REMOVE CERTAIN PISTONS, CONNECTING RODS AND PISTON PINS FROM PARTS STOCKS - 3500 - SERIES ENGINES - PI7101 - WORLDWIDE
  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.
REMOVE CERTAIN PISTONS, CONNECTING RODS, AND PISTON PINS FROM PARTS STOCKS 3500 Series Engines, 1214, 1225, 1218, PI7101 U-53 A-35 AU-44 B-19 C-49 E-32 O-39 SEE JULY 6, 1984 parts stock action only Problem Pistons with Part Numbers 4W4746, 8N7808, and 2W3189 should not be used for service replacements for pistons in any 3500 Series Engine. Some 8N7808 Pistons have experienced oil passage cracking. There has been an unacceptable rate of wear in rod eye bushings with the 4W4746 Piston. A new improved piston is now used for longer service life and improved reusability. The surface finish on 7N2393 Piston Pins and on the bushings in 1W4300, 1W4800 and in certain 8N9647 Connecting Rods does not meet the new specifications. A new piston pin and an improved 1W4800 Connecting Rod are used in production to provide a smoother surface finish. Action Requested Remove from parts stocks any 4W4746, 8N7808, and 2W3189 Pistons. Some 4W4746 Pistons may have been reworked to the latest design, and, if so, the Part Number 4W7402 will be stamped on the bottom of the pin boss. These pistons do not need to be removed from parts stocks. Remove from parts stocks any 1W4800 Connecting Rods that wer received before August 1, 1983. Any 1W4800 Connecting Rods received after this date have the correct surface finish. Remove from parts stocks any 1W4300 and 8N9647 Connecting Rods. Remove from parts stocks any 7N2393 Piston Pins. Dealers should make sure that any marine customers that are required to carry on-board spare parts have their parts stocks checked and replaced as necessary. Warranty Allowances Submit one claim for all the affected parts removed from parts stocks. Dealers outside of the United States and Canada should not claim any 1W4800 Connecting Rods. See "Parts Disposition." Parts Disposition U. S. and Canadian Dealers Return all Pistons, Connecting Rods, and Piston Pins to Pioneer Park Claims Room, Attn: J. E. Williams. Send Factory Service Engineering copy (black or legible copy) of the Claim with the parts. Send blue copy of Claim to AB6D (Canadian - AB6C) noting on this copy that the parts have been sent to Pioneer Park. All Other Dealers Hold all 1W4800 Connecting Rods removed from parts stocks. Do not submit a parts claim for these rods. This Service Letter will be followed up with a specific procedure for rod rework and an appropriate warranty claim procedure. Dispose of all other specified parts in accordance with your Warranty Parts Handling bulletin. Termination Date June 30, 1985.