NOTE: If there is lack of power, excessive oil consumption or poor fuel mileage, measure the cylinder compression pressure.
1. WARM UP ENGINE
2. REMOVE SPARK PLUGS
3. DISCONNECT HIGH-TENSION CORD FROM DISTRIBUTOR
4. MEASURE CYLINDER COMPRESSION PRESSURE
(a) Insert a compression gauge into the spark plug hole.
(b) Fully open the throttle valve,
(c) While cranking the engine with the starter motor, measure the compression pressure.
NOTE: Always use a fully charged battery to obtain engine revolution of more than 250 rpm.
(d) Repeat steps (a) through (c) for each cylinder.
11.5 kg/cm* 1164 psi, 1,128 kPa) Minimum pressure:
9.0 kg/cm2 (128 psi, 883 kPa) Difference between each cylinder:
(e) If cylinder compression in one or more cylinders is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps (a) through (c) for the cylinder with low compression.
• If adding oil helps the compression, changes are that the piston rings and/or cylinder bore are worn or damaged.
• If pressure stays low, a valve may be sticking or seatied improperly, or there may be leakage past the gasket.
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