0307072 JOHNSON SCREW, Friction band

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 "PS8955" 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.
This Revised Service Letter replaces the April 30, 1997 (Revised August 1997) Service Letter. Changes have been made to the TERMINATION DATE, Parts Needed and Rework Procedure.
Termination Date
October 31, 1998Problem
The 4P9222 Air Cleaner Group on certain 3408C Marine Engines uses a 4P7921 Hose in the closed fumes disposal system which is not oil resistant and can deteriorate over a period of time.
The 4P9219 Air Cleaner Group on certain 3412C Marine Engines uses a 7E0118 Hose in the closed fumes disposal system which is not oil resistant and can also deteriorate.
Affected Product
Model & Identification Number
3408C (8RG1-371)
3412C (3JK1-876)
3412 (7BL1-133)
Parts Needed
2 - 1411015 Hose (for 3412, 3412C Marine Engines)2 - 1425706 Hose (for 3408C Marine Engines)Action Required
Parts Stock
Remove all 7E0118 and 4P7921 Hose from parts stock.
Affected Product
See the attached rework procedure.
Service Claim Allowances
Parts Stock
Submit one claim for all 7E0118 and 4P7921 Hose removed from parts stock.
Affected Product
Add the following labor hours if required:
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
Attach.(1-Rework Procedure)Rework Procedure
3408C
1. Remove two 4P7921 Hoses and discard.2. Inspect the turbo compressor wheels for tar residue. If the inspection shows an oil film only, do not clean, proceed to Step 8.
3. If no tar residue is visible, proceed to Step 8.4. If tar residue is visible on the compressor wheel(s), remove the compressor housing(s) and clean the residue from the housing(s) and the wheel(s).5. Inspect the aftercooler core(s) for tar residue.6. If no tar residue is visible in the aftercooler core, reassemble and proceed to Step 8.7. If tar residue is visible in the aftercooler core(s), remove and clean the core(s) then reassemble.8. Install two 1425706 Hoses. 3412C
1. Remove two 7E0118 Hoses and discard.2. Inspect both turbo compressor wheels for tar residue. If the inspection shows an oil film only, do not clean, proceed to Step 8.
3. If no tar residue is visible, proceed to Step 8.4. If tar residue is visible on the compressor wheel(s), remove the compressor housing(s) and clean the residue from the housing(s) and the wheel(s).5. Inspect the aftercooler core(s) for tar residue.6. If no tar residue is visible in the aftercooler core(s), reassemble and proceed to Step 8.7. If tar residue is visible in the aftercooler core(s), remove and clean the core(s) then reassemble.8. Install two 1411015 Hoses. Hose ends have different inside diameters, reverse ends if hose does not fit initially.