RING-RETAINING 4L9020 - Caterpillar

Probable Causes
Cylinder head gasket
Cylinder head
Cylinder blockRecommended Actions
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Table 1
Troubleshooting Test Steps Values Results
1. Cylinder Head Gasket
A. Remove the cylinder head. Refer to Disassembly and Assembly, "Cylinder Head - Remove".
B. Inspect the cylinder head gasket for faults and any signs of leakage.
Cylinder head gasket
Result: The cylinder head gasket does not show signs of damage or leakage.
Repair: Install a new cylinder head gasket and install the cylinder head. Refer to Disassembly and Assembly, "Cylinder Head - Install" .
Result: The cylinder head gasket shows signs of damage or leakage.
Proceed to Test Step 2.
2. Cylinder Head
A. Check for cracks in the cylinder head. Perform a leak test on the cylinder head. Refer to System Operation, Testing and Adjusting, "Cylinder Head - Inspect" for the correct procedure.
Cylinder head
Result: A fault was found in the cylinder head.
Repair: Repair the cylinder head or replace the cylinder head. Install the cylinder head. Refer to Disassembly and Assembly, "Cylinder Head - Install".
Result: A fault was not found in the cylinder head.
Proceed to Test Step 3.
3. Cylinder Block
A. Inspect the top face of the cylinder block for faults and signs of leakage.
Refer to Systems Operation, Testing, and Adjusting, "Cylinder Block - Inspect" for the correct procedure.
Cylinder block
Result: A fault was found in the cylinder block.
Repair: Repair the cylinder block or replace the cylinder block. Inspect the top deck. Refer to the Reuse and Salvage Guidelines for the proper inspection procedure.
Result: No fault was found in the cylinder block.
Install the cylinder head. Refer to Disassembly and Assembly, "Cylinder Head - Install".
Contact the Dealer Solutions Network (DSN).