PLUG-SEAL 7G7918 - Caterpillar

Caterpillar: Confidential Yellow
PSP FOR IMPROVED RETENTION OF PIPE BETWEEN THE LEFT TURBOCHARGER AND THE AFTERCOOLER AND COMPRESSOR WHEEL FAILURES ON 785 TRUCKS - MAILED US AND CANADA, COFA, COSA, LIMITED CACO
  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.
U-120 A-57.1 AU-74 O-68 1052, 1063 PS4174 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 "PS4174" as Part Number and "7755" as Group Number. Termination Date
July 31, 1989
Problem
Several problems have been reported on the turbocharger. Problem 1 - The pipe that connects the left turbocharger to the aftercooler can move out of the turbocharger during operation. An improved joint is obtained by using a new turbocharger housing (with two threaded bosses, one on the top and one on the bottom), a new tube and a C-shaped retainer. The C-shaped retainer is also to be used between the right turbocharger and the pipe to the aftercooler. Problem 2 - Failures of the center housing in the area of the clamps and the compressor wheel. A new center housing that is more resistant to high temperatures and a new stronger compressor wheel can be installed.
Affected Product
Model Identification Number Problem 1 785 8GB1 - 230 Problem 2 785 8GB1 - 276, 278 - 281, 284, 321, 368 - 370
Parts Needed
Problem 1 1 - 7C5687 Pipe 2 - 5M2894 Washer 2 - S509 Bolt 1 - *7W2299 Housing-Compressor 2 - 7W1944 Retainer 4 - 6V3917 Seal (if needed) * Not needed if a 9Y1490 Turbocharger Group is used on left turbocharger in Problem 2. Also, for 8GB1 -