Yamaha EF1000iS, Service Manual

Page: 55 / 109

3-25
CRANKSHAFT, PISTON AND PISTON RING
1
1
a
2. Measure:
9
Piston side clearance
Out of specification
→
Replace.
NOTE:
9
Clean carbon deposits from the piston ring
grooves and ring s before measuring the
side clearance.
9
Measure the side clearance at several por-
tions.
CRANKSHAFT INSPECTION
1. Measure:
9
Crankshaft runout limit
use a dial gauge
Out of specification
→
Replace.
2. Inspect:
9
Crankshaft sprocket
1
Crack/damage/wear
→
Replace the
crankshaft.
3. Measure:
9
Crank pin diameter
a
Out of specification
→
Replace the
crankshaft.
ENG
Top ring
Wear limit
Piston ring side
clearance
0.15 mm
(0.006 in)
0.06 ~ 0.11 mm
(0.002 ~ 0.004 in)
2nd ring
0.06 ~ 0.11 mm
(0.002 ~ 0.004 in)
Runout limit:
0.03 mm (0.001 in)
Crank pin diameter:
15.970 ~ 15.985 mm
(0.629 ~ 0.630 in)
Limit:
15.940 mm
(0.627 in)
7VV10-03 02.10.8 8:07 PM Page 25