Yamaha YFM400FWA 2000 5GH3-AE1, Руководство по обслуживанию

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ENG
CYLINDER AND PISTON
3.Measure:
●
Ring end gap
Out of specification
→
Replace.
NOTE:
You cannot measure the end gap on the
expander spacer of the oil control ring. If
the oil control ring rails show excessive
gap, replace all three rings.
End gap
Standard Limit
Top
ring
0.2 ~ 0.4 mm
(0.008 ~ 0.016 in)
0.65 mm
(0.026 in)
2nd
ring
0.4 ~ 0.6 mm
(0.016 ~ 0.024 in)
0.95 mm
(0.037 in)
Oil
ring
0.2 ~ 0.7 mm
(0.008 ~ 0.028 in)
—
PISTON PIN INSPECTION
1.Inspect:
●
Piston pin
Blue discoloration/grooves
→
Replace,
then inspect the lubrication system.
2.Measure:
●
Piston pin-to-piston clearance
*********************************
Measurement steps:
● Measure the piston pin outside diameter
a
.
If out of specification, replace the piston
pin.
●
Measure the piston inside diameter
b
.
●
Calculate the piston pin-to-piston clear-
ance with the following formula.
Outside diameter (piston pin):
19.993 ~ 20.000 mm
(0.7871 ~ 0.7874 in)
Piston pin-to-piston clearance =
Bore size (piston pin)
b
–
Outside diameter (piston pin)
a