Compression Test

AllData Editors Note - Ford does not provide a cranking pressure specification, only an acceptable range.

1. Make sure oil in crankcase is of the correct viscosity and at the proper level and that the battery is properly charged. Operate the vehicle until the engine is at normal operating temperature. Turn the ignition switch to the OFF position, then remove the spark plugs.
2. Place the transaxle in PARK (A/T) or NEUTRAL (M/T) and apply the parking brake.
3. Block throttle plate in the wide-open position.
4. Install a compression gauge such as Compression Tester in the No. 1 cylinder spark plug hole.
5. Install an auxiliary starter switch in the starting circuit. With the ignition switch in the OFF position, and using the auxiliary starter switch, crank the engine a minimum of five compression strokes and record the highest reading. Note the approximate number of compression strokes required to obtain the highest reading.
6. Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes.