Checking The Piston Rings - Yamaha 2004 Rhino 660 YXR660FAS Service Manual

CYLINDER AND PISTON

CHECKING THE PISTON RINGS

1. Measure:
• ring side clearance
Use a thickness gauge.
Out of specification → Replace the piston
and rings as a set.
NOTE:
Clean carbon from the piston ring grooves and
rings before measuring the side clearance.
Top ring
(0.0016 ~ 0.0031 in)
2nd ring
(0.0012 ~ 0.0028 in)
2. Position:
• piston ring
(in cylinder)
NOTE:
Insert a ring into the cylinder and push it
approximately 50 mm (2.0 in) into the cylinder.
Push the ring with the piston crown so that the
ring will be at a right angle to the cylinder bore.
a 50 mm (2.0 in)
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.
Top ring
(0.0118 ~ 0.0177 in)
2nd ring
(0.0118 ~ 0.0177 in)
Oil ring
(0.0079 ~ 0.0276 in)
4 - 36
ENG
Side clearance
Standard Limit
0.04 ~ 0.08 mm 0.13 mm
(0.0051 in)
0.03 ~ 0.07 mm 0.13 mm
(0.0051 in)
End gap
Standard Limit
0.30 ~ 0.45 mm 0.70 mm
(0.0276 in)
0.30 ~ 0.45 mm 0.80 mm
(0.0315 in)
0.20 ~ 0.70 mm
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