Compression Check: Testing and Inspection
INSPECT COMPRESSIONa. Warm up and stop the engine.
b. Remove the circuit opening relay.
c. Remove the V-bank cover.
d. Remove the air cleaner assembly.
e. Remove the ignition coils.
f. Remove the spark plugs.
g. Inspect the cylinder compression pressure.
(1) Insert a compression gage into the spark plug hole.
SST 09992-00500
(2) Fully open the throttle.
(3) While cranking the engine, measure the compression pressure.
Compression pressure: 1,300 kPa (13.3 kgf/cm2, 189 psi)
Minimum pressure: 1,000 kPa (10.2 kgf/cm2, 145 psi)
Difference between each cylinder: 100 kPa (1.0 kgf/cm2, 15 psi)
NOTICE:
- Use a fully-charged battery so the engine speed can be increased to 250 rpm or more.
- Inspect the other cylinders in the same way.
- Measure the compression in as short a time as possible.
(4) If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps
(1) through
(3) for cylinders with low compression.
- If adding oil increases the compression, the piston rings and/or cylinder bore may be worn or dam aged.
- If pressure stays low, a valve may be stuck or seated improperly, or there may be leakage from the gasket.