Series 50 – Section 26.13 Defective Oil Pump Assembly

Section 26.13
Defective Oil Pump Assembly

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

1. Remove the oil pump assembly; refer to "3.2.2 Cleaning and Removal of Oil Pump" .
2. Manually rotate the oil pump drive gear.
   1. If the drive gear rotates freely in the pump housing, call Detroit Diesel Technical Service Group.
   2. If the drive gear did not rotate freely; refer to "26.13.1 Oil Pump Assembly Repair" .

Section 26.13.1
Oil Pump Assembly Repair

Perform the following steps to repair the oil pump assembly:‪

1. Disassemble the oil pump assembly and replace worn or damaged components as required; refer to "3.2.3 Disassembly of Oil Pump" .
2. Reassemble the oil pump; refer to "3.2.4 Assembly of Oil Pump" .
3. Verify oil pump repair; refer to "26.13.1.1 Test Engine with Repaired Oil Pump Assembly" .

Section 26.13.1.1
Test Engine with Repaired Oil Pump Assembly

Perform the following to determine if repaired relief valve resolved low oil pressure:‪

1. Install the Diagnostic Data Reader to the vehicles Display Data Line Adaptor, see Figure "Typical Display Data Line Adaptor" ; refer to OEM guidelines.
2. Start and run the engine speed at 1800 r/min.
3. Visually examine the DDR for oil pressure reading.
   1. If the DDR indicates 241 kPa (35 lb/in.² ), at 1800 r/min, shut down the engine and disconnect the DDR. No further troubleshooting is required.
   2. If the DDR indicates less than 241 kPa (35 lb/in.² ), at 1800 r/min, shut down the engine and disconnect the DDR; call Detroit Diesel Technical Service Group.