Polaris TRAIL BOSS 325 2001, Manual

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MAINTENANCE
2.14
COMPRESSION TEST
NOTE: 4-Stroke engines are equipped with an automatic decompressor. Compression readings will vary in pro-
portion to cranking speed during the test. Average compression (measured) is about 50-90 psi during a compres-
sion test.
Smooth idle generally indicates good compression. Low engine compression is rarely a factor in running condition
problems above idle speed. Abnormally high compression can be caused by a decompressor malfunction, or
worn or damaged exhaust cam lobes. Inspect camshaft and automatic decompression mechanism if compres-
sion is abnormally high.
A cylinder leakage test is the best indication of engine condition on models with automatic decompression. Follow
manufacturer’s instructions to perform a cylinder leakage test. (Never use high pressure leak tester as crankshaft
seals may dislodge and leak).
ENGINE MOUNTS
Inspect rubber engine mounts (A) for cracks or damage.
FASTENER TORQUE - ENGINE
Check engine fasteners and ensure they are tight.
Cylinder Leakage
Service Limit: 10 %
(Inspect for cause if leakage exceeds 10%)
A
A