Arctic Cat Sno Pro 120 Service Manual page 124

2. The trueness (out-of-roundness) is the difference
between the highest and lowest reading. Maximum
trueness (out-of-roundness) must not exceed 0.004 in.
PISTON SKIRT/CYLINDER
CLEARANCE
1. Measure each cylinder front to back about 1 in. from
the bottom of each cylinder.
2. Measure the corresponding piston skirt diameter at a
point 1 cm above the piston skirt at a right angle to
the piston-pin bore. Subtract this measurement from
the measurement in step 1. The difference (clear-
ance) must be within 0.0041-0.0053 in.
PISTON-RING END GAP
1. Place each piston ring in the wear portion above the
exhaust port of its respective cylinder. Use the piston
to position each ring squarely in each cylinder.
2-104
2. Using a feeler gauge, measure each piston-ring end
gap. Acceptable ring end gap must be within 0.0120-
0.0196 in.
FC044
PISTON PIN AND PISTON-PIN
BORE
1. Measure the piston pin diameter at each end and in
the center. Acceptable piston pin measurement must
be within 0.8659-0.8661 in. If any measurement var-
ies by more than 0.001 in., the piston pin and bearing
must be replaced as a set.
0725-586
2. Insert a snap gauge into each piston-pin bore; then
remove the gauge and measure it with a micrometer.
The diameter measurement must be within 0.8661-
0.8665 in. Take two measurements to ensure accuracy.
AC091
FC045
IO012
AC092