MBE 4000 DDEC VI Troubleshooting – Section 15.9 Defective Suction Pipe

Section 15.9
Defective Suction Pipe

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

1. Remove suction pipe, refer to MBE 4000 Service Manual (6SE420), Chapter 3, “Lubrication System - Oil Pump and Suction Pipe”.
2. Visually inspect suction pipe.
   1. If no stress cracks, twisting, or cracked flange are found, check for defective crankshaft main bearing shells; refer to "15.10 Defective Crankshaft Main Bearing Shells" .
   2. If stress cracks, twisting, or cracked flange are found, refer to "15.9.1 Suction Pipe Replacement" .

Section 15.9.1
Suction Pipe Replacement

Perform the following steps to replace the suction pipe:‪

1. Replace all damaged components identified during inspection and install, refer to MBE 4000 Service Manual) (6SE420) , Chapter 3, “Lubrication System - Oil Pump and Suction Pipe”.
2. Verify replacement of suction pipe; refer to "15.9.1.1 Test Engine with Replaced Suction Pipe" .

Section 15.9.1.1
Test Engine with Replaced Suction Pipe

Perform the following steps to determine if a replaced suction pipe 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.‪

1. Start and run the engine speed at rated speed.
2. Visually examine oil pressure reading.
   1. If the oil pressure at rated speed 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), check for defective crankshaft main bearing shells; refer to "15.10 Defective Crankshaft Main Bearing Shells" .