Crankcase Inspection / Bearing Fit; Crankshaft Main Bearing Inspection; Crankcase Bearing Interference Fit - Polaris INDY TRAIL RMK Service Manual

ENGINES

Crankcase Inspection / Bearing Fit

Any time crankshaft bearing failure occurs and the
case is to be reused, Polaris recommends check-
ing the bearing fit into the case halves using the fol-
lowing procedure.
1. With case halves
replacement bearing into each of the main
bearing journals to determine a basic amount
of press fit. NOTE: Do a comparison check of
all journals by manually forcing the bearing
into the bearing seats noting if any are
noticeably loose or tight.
installation will be an indication of the
recommended interference fit. If the bearing
falls out of the case when the case is inverted,
or if the crankcase bearing surface is severely
galled or damaged, the case should be
replaced.

Crankcase Bearing Interference Fit:

C-3 - .0006² (.015mm)
C-4 - .001² (.025mm)

Crankshaft Main Bearing Inspection

1. Clean crankshaft thoroughly and oil main and
connecting rod bearings with Polaris Premium
2 engine oil. Carefully check each main
bearing on the shaft.
NOTE:Due to extremely close tolerances, the bearings must be inspected visually, and by feel. Look for signs
of discoloration, scoring or galling. Turn the outer race of each bearing. The bearings should turn smoothly and
quietly. The inner race of each bearing should fit tightly on the crankshaft. The outer race should be firm with
minimal side to side movement and no detectable up and down movement. Replace any loose or rough bearings.
3.54
cleaned, press a
Normal hand