Checking The Crankcase; Checking The Piston Pin - Yamaha MZ360 Service Manual

PISTON, CAMSHAFT, CRANKCASE, AND CRANKSHAFT
a

CHECKING THE CRANKCASE

1.
Check:
• Crankcase
Damage  Replace.
• Bearing
Noise/wear/rotational failure  Replace.

CHECKING THE PISTON PIN

1.
Check:
• Piston pin
Blue discoloration/grooves  Replace the piston
pin and then check the lubrication system.
2.
Measure:
• Piston pin hole inside diameter "a"
Out of specification  Replace.
Piston pin hole inside diameter:
Limit:
3.
Measure:
• Piston pin diameter "a"
Out of specification  Replace.
Piston pin diameter:
Limit:
a
4.
Check:
• Check that the piston pin enters smoothly into the
piston pin hole.
TIP
If the piston pin fits too tight into the piston, check the pis-
ton pin hole. If there is any protrusion, use a knife or
scraper to gently remove it so that piston pin can be
pushed in smoothly with your fingers.
3-53
20.004–20.015 mm (0.7872–0.7874 in)
20.045 mm (0.7892 in)
19.995–20.000 mm (0.7872–0.7874 in)
19.975 mm (0.7864 in)
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