MBE 4000 DDEC VI Troubleshooting – Section 15.11 Defective Oil Pump Assembly

Section 15.11
Defective Oil Pump Assembly

To determine if a defective oil pump is causing low oil pressure, perform the following steps:‪

1. Remove the oil pump assembly; refer to MBE 4000 Service Manual (6SE420), Chapter 3, “Lubrication System — Oil Pump”.
2. Manually rotate the oil pump drive gear.
   1. If the drive gear rotates freely in the pump housing, call Detroit Diesel Customer Support Center at 313-592-5800.
   2. If the drive gear does not rotate freely, replace the oil pump assembly and verify repair; refer to "15.11.1 Test Engine with Replaced Oil Pump Assembly" .

Section 15.11.1
Test Engine with Replaced Oil Pump Assembly

Perform the following steps to determine if oil pump replacement resolved low oil pressure:‪

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.‪

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 speed at rated speed.
2. Visually examine the oil pressure reading.
   1. If the oil pressure at rated speed is 241 kPa (35 psi) or more, no further troubleshooting is required. Shut down the engine.
   2. If the oil pressure at rated speed is less than 241 kPa (35 psi), shut down the engine and call Detroit Diesel Customer Support Center at 313-592-5800.