Arctic Cat Sno Pro 120, Service Manual

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To select the correct rod bearing insert, read the number
stamped on the crankshaft counterweight; then read the
number stamped on the connecting rod cap. Refer to the
following chart to select the correct bearing.
Connecting Rod Bearing Selection
To select the correct thrust bearing for proper crankshaft
end clearance, use the following procedure.
1. Install the main bearing upper half inserts in the
crankcase; then place the crankshaft into position.
2. Select a thrust bearing (blue or green) and install making
sure the oil relief (A) is directed toward the crankshaft.
ZJ074A

NOTE: Always install the correct thrust bearing
(from above) on MAG-side; then use proper bearing
from the following chart on the PTO-side of the main
bearing journal to obtain clearance.
Thrust Bearing Selection
3. Using a feeler gauge, measure between the crankcase
and crankshaft on the side opposite the thrust bearing.
ZJ111A
4. Use the reading obtained to select the correct thrust
bearing from the chart.
5. Install the selected thrust bearing; then using a feeler
gauge, check that the clearance is as specified.
Assembling

NOTE: Arctic Cat recommends that new gaskets,
seals, and O-rings be installed whenever assembling
the engine.

NOTE: For assembling purposes, use oil-dissolv-
able molybdenum disulfide grease as engine-assem-
bly grease.
1. Install one piston pin circlip into one of the pistons
making sure the open end is directed either up or
down. Place the connecting rod in position making
sure the identification number on the rod cap (A) is
aligned with the intake side of the piston (B).
ZJ070A
2. Install the piston pin and piston pin circlip making
sure the open end is directed either up or down.
Repeat for the other piston/connecting rod assembly.
3. With the piston rings installed, lubricate each piston
and cylinder with engine oil; then with the dots on
the top of the pistons directed towards the exhaust
side of the engine, install the piston assemblies into
the cylinder.
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
NOTE: Prior to installing the pistons, make sure the
oil ring end gaps are on directly opposite sides of the
piston, and the compression ring end gaps are 90°
from one another.
Rod Crankshaft
1 2 3
1 Green
p/n 3007-109
Black
p/n 3007-110
Brown
p/n 3007-111
2 Black
p/n 3007-110
Brown
p/n 3007-111
Yellow
p/n 3007-112
Feeler Gauge Reading Color
0.100-0.102 in. White
0.099-0.100 in. Yellow
0.098-0.099 in. Green
0.097-0.098 in. Blue
0.096-0.097 in. Black
0.095-0.096 in. Red