Polaris 2012 Sportsman Forest 500 International, Service Manual

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3.45
ENGINE
3
9923412 - 2012 Sportsman 400/500 and EFI Tractor Service Manual
© Copyright 2011 Polaris Sales Inc.
4. Measure the distance from the PTO crankcase mating
surface to the bearing using the same method
outlined in Step 1, 2, and 3.
5. Add the readings obtained in Step 3 and Step 4.
6. Subtract the counter balancer shaft width measured
in Step 2 from the figure obtained in Step 5.
7. Subtract the thickness of the existing shim from the
result of Step 6 to determine if a different shim is
needed. The result must be within the specified range
listed at below.
Oil Pump Shaft End Play Adjustment
1. Make sure the pump shaft bearing is firmly seated in
the Magneto side crankcase.
2. Measure the distance from the magneto crankcase
mating surface to the bearing using a dial caliper and
a straight edge. Subtract the thickness of the
straightedge and record.
3. Install the gear on the oil pump and measure the width
of the pump and gear. Subtract this measurement
from the measurement recorded in Step 2.
4. Subtract the thickness of the existing shim from the
result of Step 3 to determine if a different shim is
needed. See “Pump Shaft End Play” specification
below.
ENGINE REASSEMBLY
Pump Shaft Oil Seal Installation
1. Install the seal from the outside of the crankcase
(water pump side) with the spring facing inward,
toward the pump shaft bearing.
2. Drive or press the seal into place using a 25 mm
(.985") seal driver, until flush with the outer edge of the
seal bore.
3. Lubricate the seal lip with grease.
Crankshaft / Counter Balance / Oil Pump
Installation
Lubricate all bearings with clean engine oil before
assembly.
Use the Crankshaft/Water Pump Installation Kit (PN
2871283) to prevent damage to the crankshaft and main
bearings during installation.
1. Install the crankshaft into the PTO side crankcase.
Screw the threaded rod into the crankshaft until the
threads are engaged a minimum of one inch
(25.4mm).
2. Install the collar, washer, and nut onto the threaded
rod. Hold the crankshaft and tighten the nut to draw
the crankshaft into the main bearings until fully
seated. Loosen the nut and remove the threaded rod
from the crankshaft. If removal is difficult, install two
nuts on the end of the threaded rod and tighten
against each other.
Counter Balancer Shaft End Play:
.008”-.016” (.02-.04 cm)
Pump Shaft End Play:
.008”-.016” (.02-.04 cm)