Section 03-00: Engine, Service
1996 All F-150, F-250, F-350, F-Super Duty and Bronco Vehicles Equipped with 4.9L, 5.0L, 5.8L or 7.5L Gasoline Engines, and 7.3L Diesel Engines Workshop Manual
SERVICE PROCEDURES

Oil Leak and Valve Guide Seal Test

The cylinder leakage detector can be used to test for engine oil leaks and to check the valve seals for leakage.

  1. Plug all crankcase openings except the one used for connecting the leakage detector.

  1.  CAUTION: Use extreme caution when pressurizing crankcase. Applying air pressure above specified pressure risks damage to seals, gaskets and core plugs. Under no circumstances should pressure be allowed to exceed 27 kPa (4 psi).

    Connect the detector to a crankcase opening (oil level indicator tube (6754) is convenient) and adjust the air pressure to approximately 20 kPa (3 psi).

  1. Using a solution of liquid soap and water, brush the solution along the gasket sealing surfaces and bearing seals. Look for bubbles or foam.

  1. Remove the spark plugs (12405) and rotate the engine (6007) slowly with a wrench. Check for large amounts of air escaping into the cylinders as each intake and exhaust valve opens.

    The spark plugs on the leaking cylinders will probably show deposits of burned oil.