Engine Compression

1987 Ford Cutaway 6.9 1SECTION Engine Compression
  1. Prior to checking compression, be sure batteries are fully charged. DO NOT add oil to cylinders. Adding oil may cause hydrostatic lock and extensive engine damage.
  2. Start and warm engine to normal operating temperature. Turn ignition off. Remove air cleaner and/or intake opening cover. Disconnect injection pump cut-off solenoid.
  3. Remove all glow plugs and insert compression gauge in No. 1 cylinder glow plug hole. With ignition off, crank engine through at least 6 compression strokes. Note number of strokes required to obtain highest reading. Repeat check on each cylinder, cranking engine same number of compression strokes.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.