Polaris Ranger 500 2x4 2007, Service Manual

Page: 97 / 345

3.38
ENGINE
NOTE: Due to extremely close tolerances and
minimal wear, the bearings must be inspected
visually, and by feel. Look for signs of discoloration,
scoring or galling. Turn the inner race of each
bearing. The bearings should turn smoothly and
quietly. The outer race of each bearing should fit
tightly in the crankcase. The inner race should be
firm with minimal side to side movement and no
detectable up and down movement.
3. Support the crankcase and drive or press the main bearings
out of each crankcase.
4. To remove balancer shaft bearings and pump shaft bearing
use a blind hole bearing puller.
NOTE: Bearings are stressed during the removal
process and should not be re-used!
Oil Seal / Mechanical Seal Removal
(Engine Disassembled)
NOTE: The water pump mechanical seal can be
removed without removing the engine. Refer to
Water Pump Mechanical Seal Installation.
Replace the pump shaft seal and water pump mechanical seal
whenever the crankcase is disassembled.
1. Remove the pump shaft bearing from the Magneto (right
hand) side crankcase.
2. Pry out the oil seal, noting the direction of installation with
the spring side facing IN (toward inside of case).
3. Drive the water pump mechanical seal out of the crankcase
from inside to outside. Note: The new mechanical seal
must be installed after the crankcases are assembled, using
a special tool. See Mechanical Seal Installation.
Crankcase Inspection
1. Remove all traces of gasket sealer from the crankcase
mating surfaces. Inspect the surfaces closely for nicks,
burrs or damage.
2. Check the oil pump and oil passage mating surfaces to be
sure they are clean and not damaged.
Bearing Installation
NOTE: To ease bearing installation, warm the
crankcase until hot to the touch. Place the bearings
in a freezer.
1. Install the bearings so the numbers are visible.
2. Drive or press new bearings into the crankcases, using the
proper driver. CAUTION: Press only on outer race of
bearing to prevent bearing damage.
• 70 mm (2.755") driver- for crankshaft main bearings.
• 46 mm (1.810") for counter balancer bearings.
• 28 mm (1.100") for pump shaft bearing.
End Play Inspection / Adjustment
Before reassembling the crankcase the following steps should
be performed to determine the amount of crankshaft, counter
balancer shaft, and pump shaft end play: Excessive end play
may cause engine noise at idle and slow speeds. Too little play
will side load the bearings which may lead to premature bearing
failure.
Crankshaft End Play Adjustment
1. Make sure all bearings are firmly seated in both the Mag
and PTO crankcase.