general information - Martin Nez

ENGINE 3-49PISTON AND PISTON RINGPISTON DIAMETER• Using a micrometer, measure the piston outside diameter at15 mm A from the piston skirt end.• If the measurement is less than the limit, replace the piston. Piston diameter:Service Limit: 66.845 mmat 15 mm from the skirt end 09900-20203: Micrometer (50 – 75 mm)PISTON-TO-CYLINDER CLEARANCE• Subtract the piston diameter from the cylinder bore diameter.(3-48)• If the piston-to-cylinder clearance exceeds the service limit,replace the crankcase set or the piston, or both. Piston-to-cylinder clearance:Service Limit: 0.120 mmPISTON PIN AND PIN BORE• Measure the piston pin bore inside diameter using the smallbore gauge.• If the measurement is out of specifications replace the piston. Piston pin bore I.D.:Service Limit: 14.030 mm 09900-20602: Dial gauge (1/1 000 mm)09900-22401: Small bore gauge (10 – 18 mm)• Measure the piston pin outside diameter at three positionsusing the micrometer.• If any of the measurements are out of specification, replacethe piston pin. Piston pin O.D.:Service Limit: 13.980 mm 09900-20205: Micrometer (0 – 25 mm)