Yamaha YW125Y_ Utility Trailer User Manual


 
ENG
5-36
EAS00263
CHECKING THE PISTON RINGS
1. Measure:
8piston ring side clearance
Out of specification J Replace the pis-
ton and piston rings as a set.
TIP
Before measuring the piston ring side clearance,
eliminate any carbon deposits from the piston
ring grooves and piston rings.
Piston ring side clearance
Top ring
0.02 ~ 0.08mm (0.0008 ~ 0.0031in)
<Limit>: 0.13mm (0.0051in)
2nd ring
0.02 ~ 0.06mm (0.0008 ~ 0.0024in)
<Limit>:0.12mm (0.0047in)
CYLINDER AND PISTON
a
2. Install:
8piston ring
(into the cylinder)
TIP
Level the piston ring into the cylinder with the
piston crown.
a 20mm (0.79in)
3. Measure:
8piston ring end gap
Out of specification J Replace the pis-
ton ring.
TIP
The oil ring expander spacer’s end gap cannot
be measured. If the oil ring rail’s gap is exces-
sive, replace all three piston rings.
Piston ring end gap
Top ring
0.10 ~ 0.25mm (0.0039 ~ 0.0098in)
<Limit>: 0.50mm (0.0197in)
2nd ring
0.25 ~ 0.40mm (0.0098 ~ 0.0157in)
<Limit>: 0.75mm (0.0295in)
Oil ring
0.20 ~ 0.70mm (0.0079 ~ 0.0276in)
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