Use this procedure in order to troubleshoot low oil pressure. Use this procedure if one of the following event codes is active. Refer to Troubleshooting, “Event Codes” for information about event codes and the default trip points for these codes. You must access the monitoring system on Caterpillar Electronic Technician (ET) in order to view the current trip points for these codes.
Event Code | ||
---|---|---|
Code and Description | Conditions which Activate the Code | System Response |
E043(3) Low Engine Oil Pressure Shutdown | The engine oil pressure is less than the trip point and the delay time has expired. | The code is logged. The engine is shutdown. |
E100(1) Low Engine Oil Pressure Warning | The engine oil pressure is less than the trip point and the delay time has expired. | The code is logged. |
100-1 Low Oil Pressure (Warning) | The engine oil pressure is less than the trip point and the delay time has expired. | The code is logged. The diagnostic lamp will flash. The alarm lamp will illuminate. |
100-11 Very Low Oil Pressure (Derate) | The engine oil pressure is less than the trip point and the delay time has expired. | The engine power is derated. The code is logged. The diagnostic lamp will flash. The alarm lamp will flash. |
100-11 Very Low Oil Pressure (Shutdown) | The engine oil pressure is less than the trip point and the delay time has expired. | The code is logged. The engine will be shutdown after 30 seconds. |
Probable Causes
- Low engine oil level
- Incorrect viscosity
- Contaminated engine oil
- Faulty oil pressure sensors
- Poor circulation of the engine oil
- Worn components
Recommended Repairs
Low Engine Oil Level
Check the oil level. Add oil, as needed.
Incorrect Viscosity
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.
Contaminated Engine Oil
Engine oil that is contaminated with another liquid will cause low engine oil pressure. High engine oil level can be an indication of contamination. Obtain an analysis of the engine oil. Determine the reason for contamination of the engine oil and make the necessary repairs. Change the engine oil and the engine oil filter. For the correct engine oil to use, refer to the Operation and Maintenance Manual.
Faulty Engine Oil Pressure Sensors
Use Cat ET to compare the readings of the filtered engine oil pressure and the unfiltered engine oil pressure while the engine is OFF. Both readings should be close to zero pressure.
If a reading is significantly different from zero, refer to Troubleshooting, “Sensor Signal (Analog, Active) – Test”.
Poor Circulation of the Engine Oil
Several factors could cause poor circulation of the engine oil:
- The engine oil filter is clogged. Replace the engine oil filter.
- An engine oil line or a passage for engine oil is disconnected or broken.
- The engine oil cooler(s) is clogged. Thoroughly clean the engine oil cooler(s).
- There is a problem with a piston cooling jet. Breakage, a restriction, or incorrect installation of a piston cooling jet will cause seizure of the piston.
- The inlet screen of the suction tube for the engine oil pump can have a restriction. This restriction will cause cavitation and a loss of engine oil pressure. Check the inlet screen on the suction tube and remove any material that may be restricting engine oil flow.
- The suction tube is drawing in air. Check the joints of the tube for cracks or for a damaged O-ring seal.
- There is a problem with the engine oil pump. Check the gears of the engine oil pump for excessive wear. Engine oil pressure is reduced by gears that have too much wear.
- The engine oil pump’s pressure regulating valve or a bypass valve is stuck in the open position. Clean the valve. Replace parts, if necessary.
Worn Components
Excessive clearance at the crankshaft or camshaft bearings will cause low engine oil pressure. Also, inspect the clearance between the rocker arm shafts and the rocker arms. Check the engine components for excessive clearance.
Obtain an analysis of the engine oil. Check the analysis for the level of wear metals in the engine oil.