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Home >> Mercury >> 1997 >> Villager LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Preliminary Inspection & Adjustments >> Mechanical Inspection >> Compression
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Mechanical Inspection: Compression

Check engine mechanical condition using a compression gauge, vacuum gauge or engine analyzer. If using engine analyzer, see engine analyzer manual for specific instructions. Compression should be 175 psi (1200 kPa). Minimum compression should be 130 psi (883 kPa). Maximum compression variation allowed between cylinders is 14 psi (97 kPa).

WARNING: Because fuel injectors on many models are triggered by the ignition switch, DO NOT use ignition switch during compression tests on fuel injected vehicles. Use a remote starter to crank engine to prevent fire hazard or engine oiling system contamination.