VALVE GP-RELIEF 1151375 - Caterpillar

Probable Causes
Engine oil level
Engine oil cooler bypass valve
Engine oil cooler core
Engine coolant temperatureRecommended Actions
Table 1
Troubleshooting Test Steps Values Results
1. Check the Engine Oil Level
A. Use the engine oil dipstick to check for the correct oil level.
Engine Oil Level
Result: The engine oil level is OK.
Proceed to Test Step 2.
Result: The engine oil level is NOT OK.
Repair: Add oil to the crankcase.
2. Check the Engine Oil Cooler Bypass Valve
A. Inspect the components of the engine oil cooler bypass valve for damage. Clean the engine oil cooler bypass valve and clean the bore for the valve. Ensure that the bypass valve is not stuck in the open position.
Engine Oil Cooler Bypass Valve
Result: The engine oil cooler bypass valve is OK.
Proceed to Test Step 3.
Result: The engine oil cooler bypass valve is NOT OK.
Repair: Repair or replace the engine oil cooler bypass valve.
3. Check the Engine Oil Cooler Core
A. Check the engine oil cooler core for damage and for plugging.
Engine Oil Cooler Core
Result: The engine oil cooler core is not damaged or plugged.
Proceed to Test Step 4.
Result: The engine oil cooler core is damaged and/or plugged.
Repair: Clean the engine oil cooler core or replace the engine oil cooler core.
4. Check the Engine Coolant Temperature
Engine Coolant Temperature
Result: The engine coolant temperature is normal.
Return the engine to service.
Result: The engine coolant temperature is not normal.
Repair: Refer to troubleshooting without a diagnostic code Troubleshooting, "Coolant Temperature Is Too High".