KIT-PISTON SEAL 3924595 - Caterpillar

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 "PS5789" 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.
Termination Date
January 31, 2001Problem
Malfunction of the main hydraulic pump on certain 330 and 330L Excavators. This malfunction may occur due to wear and/or breakage of poppet type shuttle valve in the pump regulator. A new ball type shuttle valve can be used in place of the poppet shuttle valve.
Affected Product
Model & Identification Number
330L (8RL179-Up, 9ML166-Up)
Parts Needed
1 - 1597781 Head Group - PumpAction Required
Refer to the service manual for related service in this rework.
1. Remove the pump assembly from the machine.2. Remove head group from the regulator.3. Install new 1597781 Head Group on regulator.4. Install all parts to the cover.5. Restore all parts according to the service manual.Service Claim Allowances
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.