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1. Warm up engine.
2. Turn ignition switch off.
3. Release fuel pressure (See How to Change Fuel Filter)
4. Remove all spark plugs.
5. Disconnect distributor center cable.
6. Attach a compression tester to No. 1 cylinder.
7. Depress accelerator pedal fully to keep throttle valve wide open.
8. Crank engine (let it turn over 7 times) and record highest gauge indication.
9. Repeat the measurement on each cylinder as shown above.
Note: Always use a fully charged battery to obtain specific engine revolution.

Compression Pressure kPa (kg/cm2, psi) / RPM
Standard = 1,236 (12.6, 179) / 300
Minimum = 1,040 (10.6, 151) / 300
Difference limit between cylinders = 98 (1.0, 14) / 300

10. If cylinder compression in one or more cylinders is low, pour a small amount of engine oil into the cylinders through the spark plug hole and re-test compression.

* If adding oil helps compression, piston rings may be worn or damaged. If so, replace piston rings after checking piston.

* If pressure stays low, a valve may be sticking or seating improperly. Inspect and repair valve and valve seat.

* If compression in any two adjacent cylinders is low and if oil does not help compression, there is a leak past the gasket surface. If so, replace cylinder head gasket.