Arctic Cat Sno Pro 120 Service Manual page 93

4. Position the indicator contact point against the crank-
shaft at location point C (center). Zero the indicator
and rotate the crankshaft slowly. Note the amount of
crankshaft runout (total indicator reading).
5. If runout exceeds 0.002 in. at any of the checkpoints,
the crankshaft must be either straightened or
replaced.
Assembling
 NOTE: Use new gaskets and seals when assem-
bling the engine.
 NOTE: Prior to assembling the engine, use parts
cleaning solvent and compressed air and thoroughly
clean the threaded holes of the crankcase and cylin-
ders to properly tighten.
! WARNING
Always wear safety glasses when drying components
with compressed air.
 NOTE: When the use of a lubricant is indicated, use
recommended Arctic Cat Injection Oil.
1. Place the upper crankcase half (with its bottom side
up) on two blocks of wood.
CAUTION
To prevent damage to the crankshaft, crankshaft bear-
ings, or seals, make sure to always lift the crankshaft
from both ends.
2. Lightly grease the inner lips of the crankshaft seals;
then slide them onto the crankshaft.
3. Apply oil to the crankshaft bearings; then install the
crankshaft into the upper crankcase half. Be sure the
alignment hole in each bearing is positioned over its
respective dowel pin in the crankcase; then seat the
crankshaft.
 NOTE: To check the bearing for proper position,
place the point of a sharp tool into the dimple found
in the bearing race. Strike the tool with the palm of
the hand in either direction. If the bearing moves, it
isn't positioned correctly and must be rotated until it
drops onto the dowel pin.
If the bearings are not properly seated during assembly,
the crankcase halves will not seal tightly and severe
engine damage will result.
 NOTE: Position the two center seal rings with their
FC046
end gaps 180° apart (up on one and down on the
other); then apply a thin coat of High-Temp Sealant to
the entire bottom half of the crankcase sealing sur-
face.
4. Install the four crankcase dowel pins.
5. Install crankcase lower half. Install eight 8 mm and
four 6 mm cap screws.
6. Tighten the 8 mm cap screws in two steps to 17 ft-lb
and the 6 mm cap screws to 96 in.-lb using the pat-
tern shown.
CAUTION
2
CM036A
737-027A
2-73