41
CC400D
2. Remove each ring by working it toward the top of
the piston while rotating it out of the groove.
NOTE: When installing new rings, install as a com-
plete set only.
Measuring Piston-Ring End Gap
(Installed)
1. Place each piston ring in the wear portion of the cyl-
inder. Use the piston to position each ring squarely in
the cylinder.
2. Using a feeler gauge, measure each piston-ring end
gap. Acceptable ring end gap must be within specifi-
cations.
CC995
Measuring Piston Pin, Connecting
Rod Small End, and Piston-Pin Bore
1. Measure the piston pin outside diameter at each end
and in the center. If measurement exceeds specifica-
tions, the piston pin must be replaced.
ATV-1070
2. Inspect and measure the connecting rod small end. If
the measurement exceeds specifications, the con-
necting rod must be replaced (see Center Crankcase
Components in this section).
3. Insert an inside dial indicator into the piston-pin
bore. Take two measurements to ensure accuracy.
The diameter must not exceed specifications. If the
diameter exceeds specifications, the piston must be
replaced.
ATV-1069
Measuring Piston Skirt/Cylinder
Clearance
1. Measure the cylinder front to back in six places.
CC397D
2. Measure the corresponding piston diameter at a point
15 mm above the piston skirt at a right angle to the
piston-pin bore. Subtract this measurement from the
measurement in step 1. The difference (clearance)
must be within specifications.
Installing Piston Rings
1. Install ring expander (4) in the bottom groove of the
piston; then install the thin oil rings (3) over the
expander making sure the expander ends do not
overlap. Stagger the end gaps of the upper and lower
thin oil rings according to the illustration.
NOTE: Note the direction of the exhaust side of the
piston (5) for correct ring end gap orientation.
