Compression Check: Testing and Inspection

Compression

INSPECTION

CAUTION: After warming-up, engine becomes very hot. Be careful not to burn yourself at measurement.

1) Remove the collector cover.
2) After warming-up the engine, turn the ignition switch to OFF.
3) Make sure that the battery is fully charged.
4) Release the fuel pressure.
5) Remove all the spark plugs.
6) Fully open the throttle valve.
7) Check the starter motor for satisfactory performance and operation.
8) Hold the compression gauge tightly against the spark plug hole.

NOTE: The screw of a screw-in type compression gauge should be less than 18 mm (0.71 in) in length.

9) Crank the engine by the starter motor, and read the maximum value on the gauge when the needle of gauge is steady.





10) Perform at least two measurements per cylinder, and check that the values are correct.
Compression (fully open throttle):
Standard 981-1,177 kPa (10-12 kgf/cm2, 142-171 psi)
Limit 882 kPa (9.0 kgf/cm2, 128 psi)
Difference between cy1inders 49 kPa (0.5 kgf/cm2, 7 psi), or less
11) After inspection, install the related parts in the reverse order of removal.