MBE 4000 DDEC VI Troubleshooting – Section 15.3 Lubricating Oil Diluted With Fuel or Engine Coolant

Section 15.3
Lubricating Oil Diluted With Fuel or Engine Coolant

To determine if lubricating oil diluted with fuel or engine coolant is causing low oil pressure, perform the following steps:‪

1. Acquire a lubricating oil sample from the engine oil pan.
2. Visually examine lubricating oil sample for presence of engine coolant or fuel.
   1. If coolant or fuel are not present, check for a faulty oil pressure gauge; refer to "15.4 Faulty Oil Pressure Gauge Sensor" .
   2. If coolant or fuel are present, refer to "15.3.1 Contaminated Lubricating Oil Resolution" .

Section 15.3.1
Contaminated Lubricating Oil Resolution

Perform the following steps to resolve contaminated lubricating oil:‪

1. If coolant is present, consider head gasket replacement and repair as required.
2. If fuel is present, consider fuel nozzle replacement and repair as required.
3. Drain engine oil pan.
4. Refill engine crankcase with new oil.
5. Verify lubricating oil replacement; refer to "15.3.1.1 Test Replaced Lubricating Oil" .

Section 15.3.1.1
Test Replaced Lubricating Oil

To determine if replaced lubricating oil resolved low oil pressure, perform the following:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked.‪

1. Start and run the engine at rated speed, if the oil pressure is 241 kPa (35 psi) or more, no further troubleshooting is required.
2. If the oil pressure at rated speed is less than 241 kPa (35 psi), shut down the engine. Check for faulty oil pressure gauge sensor; refer to "15.4 Faulty Oil Pressure Gauge Sensor" .