ENGINE 3-49
PISTON AND PISTON RING
PISTON DIAMETER
• Using a micrometer, measure the piston outside diameter at
15 mm (0.6 in) A from the piston skirt end.
• If the measurement is less than the limit, replace the piston.
Piston diameter:
Service Limit: 66.88 mm (2.6331 in)
at 15 mm (0.6 in) 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 mm (0.0047 in)
PISTON PIN AND PIN BORE
• Measure the piston pin bore diameter using the small bore
gauge.
• If the measurement is out of specification, replace the piston.
Piston pin bore I.D.:
Service Limit: 14.030 mm (0.5524 in)
09900-20602: Dial gauge (1/1000 mm)
09900-22401: Small bore gauge (10 – 18 mm)
• Measure the piston pin outside diameter at three positions
using the micrometer.
• If any of the measurements is out of specification, replace the
piston pin.
Piston pin O.D.:
Service Limit: 13.980 mm (0.5503 in)
09900-20205: Micrometer (0 – 25 mm)