MBE 900 DDEC VI Troubleshooting – Section 5.13 Low Compression

Section 5.13
Low Compression

To determine if low compression is causing starting difficulty, perform the following steps:‪

1. Perform a cylinder compression test, refer to "2.2 Compression Pressure Test" .
2. Compare cylinder compression test results to specifications aslisted in Table "Compression Testing" .
   1. If cylinder pressure is below specifications, refer to "5.13.1 Low Compression Repair" .
   2. If cylinder pressure is within specifications, call Detroit Diesel Customer Support Center at 313-592-5800.

Section 5.13.1
Low Compression Repair

Perform the following steps for low compression repair:‪

1. Remove cylinder head, refer to MBE 900 Service Manual (6SE9007), engine chapter.
2. Inspect the cylinder head for worn or damaged valves, refer to MBE 900 Service Manual (6SE9007), engine chapter-valves.
3. Replace damaged valves, refer to MBE 900 Service Manual (6SE9007), engine chapter-valves.
4. Inspect the cylinder kit components for worn or damaged liners; pistons or piston rings.
5. Verify repairs made to cylinder head valve(s) or cylinder kit components; refer to "5.13.1.1 Test Engine with Repaired Cylinder Head Valve(s), and Cylinder Kit" .

Section 5.13.1.1
Test Engine with Repaired Cylinder Head Valve(s), and Cylinder Kit

To determine if the cylinder head valve and cylinder kit repair resolved starting difficulty, perform the following steps:‪

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. Attempt to start and run the engine, if the engine starts and runs, no further troubleshooting is required. Shut down the engine.
2. If the engine fails to start and run, call the Detroit Diesel Customer Support Center at 313-592-5800.