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

  1. Perform a cylinder compression test.
  2. Compare cylinder compression test results to specifications.
    1. If cylinder pressure is below specifications; refer to section .
    2. If cylinder pressure is within specifications, call Detroit Diesel Technical Service Group.

Low Compression Repair

Perform the following steps for low compression repair: ‪

  1. Remove cylinder head; refer to section .
  2. Inspect the cylinder head for worn or damaged valves; refer to section .
  3. Replace damaged valves; refer to section .
  4. Inspect the cylinder kit components for worn or damaged liners, refer to section ; pistons or piston rings; refer to section .
  5. Verify repairs made to cylinder head valve(s) or cylinder kit components; refer to section .
Test Engine with Repaired Cylinder Head Valve(s), and Cylinder Kit

Perform the following steps to determine if the cylinder head valve and cylinder kit repair resolved starting difficulty: ‪

  1. Attempt to start and run the engine.
    1. 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 Technical Service.