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COMPRESSION PRESSURE

Measurement of Compression Pressure

1.    Be surę the oil in the crankcase is at the proper level and the battery is properly charged.

2.    Warm up the engine.

3.    Turn the ignition switch off, then remove all the spark plugs.

4. Disconnect the anti-dieseling solenoid valve connector.

9. If one or morę cylinders read Iow, pour smali amount of engine oil into the cylinders through the spark pług holes.

•    If compression improves considerably, the piston rings are worn or damaged.

•    If compression does not improve, valves are sticking or seating poorly.

•    If two adjacent cylinders indicate Iow compression pressures and pouring oil into cylinders does not increase the compression, the cause may be a cylinder head gasket leak between the cylinders.

5. Install a compression tester in No. 1 cylinder.

6.    Depress the accelerator pedał fully to keep the throttle valve wide open.

7.    Crank the engine and read the highest gauge indication.

8.    Repeat the measurement on each cylinder as shown above.

Compression pressure: kPa (kg/cm², psi)/rpm Standard

1,245 (12.7, 181)/350 Minimum

981 (10.0, 142)/350

Difference limit between cylinders: