PLATE AS 8S4393 - Caterpillar

Probable Causes
Engine Oil
Low engine oil level
Incorrect engine oil
Verify the engine oil temperature.Engine Oil Cooler
Restriction in the engine oil cooler core
Engine oil cooler bypass valveEngine Coolant Temperature
High engine coolant temperatureRecommended Actions
Low Engine Oil Level
Use the engine oil dipstick to check for the correct oil level. If necessary, add engine oil to the crankcase.Incorrect Engine Oil
Make sure that the engine is supplied with the correct engine oil. For the correct engine oil to use, refer to the Operation and Maintenance Manual.Verify Oil Temperature
Check the actual engine oil temperature with a calibrated test gauge. Compare the oil temperature reading from Caterpillar Electronic Technician (ET) to the reading on the test gauge.Restriction in the Engine Oil Cooler Core
Check the engine oil cooler core for damage and for plugging. Clean the engine oil cooler core or replace the engine oil cooler core, if necessary.Engine Oil Cooler Bypass Valve
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. Replace the components of the bypass valve, if necessary.High Engine Coolant Temperature
If a high coolant temperature condition is also occurring, refer to the symptom Troubleshooting, "Coolant Temperature Is High".