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Engine Compression

Check engine compression with engine at normal operating temperature and specified cranking speed, all spark plugs removed, and throttle wide open. Release fuel pressure by removing fuel pump fuse (located in fuse block) and operate engine until it stalls. Crank engine another 2-3 times to release residual pressure.

Remove ornament cover and disconnect harness connector between ignition coil and power transistor. Crank engine at least 6 revolutions to determine engine compression. Compression reading should be as specified. See COMPRESSION SPECIFICATIONS table.

COMPRESSION SPECIFICATIONS

Application Specification
Compression Ratio 10.2:1
Normal Compression Pressure 185 psi (13 kg/cm2 )
Minimum Compression Pressure 142 psi (10 kg/cm2 )
Maximum Variation Between Cylinders 14 psi (1 kg/cm2 )