1985-1995 Polaris ATV and Light Utility Hauler Service Manual, Page 271Get this manual
ENGINES Oil Check Valve Testing Reed Valve Assembly
26Measure reed stop height in the area (A) indicatedRecommended stop height is .350" (9 mm)
27Measure the air gap of each reed valve petal as shown in the photo at rightThe air gap should not exceed .015" (.4 mm)NOTE: An early sign of reed valve failure may be hard starting28Check each reed valve petal for white stress marks or missing materialReplace if necessaryWhenever the counterbalance assembly is removed it is mandatory to verify impeller clearanceFollowing is recommended procedure for measuring water pump impeller clearance1Apply small amount of putty or clay to the top of one impeller blade (8)