COMPRESSION PRESSURE
EM-6prose procedureMeasurement of Compression Pressure
- 1Warm up engine.
- 2Turn ignition switch off.
- 3Release fuel pressure. Refer to "Releasing Fuel Pressure" in section EF & EC.
- 4Remove all spark plugs.
- 5Disconnect power transistor harness connector.
SEM354C - 6Attach a compression tester to No. 1 cylinder.
SEM355C - 7Depress accelerator pedal fully to keep throttle valve wide open.
- 8Crank engine and record highest gauge indication.
- 9Repeat the measurement on each cylinder as shown above.Always use a fully-charged battery to obtain specified engine revolution.
- 10If cylinder compression in one or more cylinders is low, pour a small amount of engine oil into cylinders through spark plug holes and retest compression.
| Specification | Value |
|---|---|
| Compression pressure — StandardStandard | 1,177 (11.77, 12.0, 171)/350kPa (bar, kg/cm², psi)/rpm |
| Compression pressure — MinimumMinimum | 981 (9.81, 10.0, 142)/350kPa (bar, kg/cm², psi)/rpm |
| Differential limit between cylindersDifferential limit between cylinders | 98 (0.98, 1.0, 14)/350kPa (bar, kg/cm², psi)/rpm |
Compression pressure — StandardStandard
1,177 (11.77, 12.0, 171)/350kPa (bar, kg/cm², psi)/rpm
Compression pressure — MinimumMinimum
981 (9.81, 10.0, 142)/350kPa (bar, kg/cm², psi)/rpm
Differential limit between cylindersDifferential limit between cylinders
98 (0.98, 1.0, 14)/350kPa (bar, kg/cm², psi)/rpm
IMPORTANT
If adding oil helps compression, piston rings may be worn or damaged. If so, replace piston rings after checking piston.
IMPORTANT
If pressure stays low, a valve may be sticking or seating improperly. Inspect and repair valve and valve seat. (Refer to S.D.S.) If valve or valve seat is damaged excessively, replace them.
IMPORTANT
If compression in any two adjacent cylinders is low and if adding oil does not help compression, there is leakage past the gasket surface. If so, replace cylinder head gasket.