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Mechanical Inspection: Compression

Engine mechanical condition can be checked using a compression gauge, vacuum gauge or engine analyzer capable of performing a relative compression test. See engine analyzer instruction manual for availability and description of relative compression feature.

CAUTION: Use a remote starter (NOT the ignition switch) to crank engine during compression test. The fuel injectors on many fuel-injected models are triggered during cranking mode. This could cause a fire hazard, flooding, crankcase contamination, hydrostatic lock or lubrication to be washed off cylinder walls.