Polaris 2012 Sportsman Forest 500 International, Service Manual

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3.50
ENGINE
9923412 - 2012 Sportsman 400/500 and EFI Tractor Service Manual
© Copyright 2011 Polaris Sales Inc.
4. Apply clean engine oil liberally to the cylinder bore and
tapered area of the sleeve. Install the cylinder with a
slight rocking motion until the rings are captive in the
sleeve.
5. Remove the ring compressor and support block.
6. Push the cylinder downward until fully seated on the
base gasket.
7. Apply a light film of oil to the threads and flange
surface of the cylinder mounting bolts.
8. Install all four bolts finger tight. Rotate the engine and
position the piston at BDC.
NOTE: If cam chain is installed, hold it up while
rotating the engine to avoid damage to the chain,
drive sprocket teeth, or tensioner blade.
9. Tighten the cylinder bolts in three steps in a criss cross
pattern and torque to specifications.
10. Install the two 6 mm bolts.
Cylinder Head Installation
Clean the gasket surfaces on the cylinder head and
cylinder.

Remove all traces of old gasket material.

Refer to disassembly photos.
1. Install the cam chain tensioner guide. Be sure bottom
end of guide is located properly in crankcase.
2. Install the two dowel pins and a new cylinder head
gasket.
3. Place the cylinder head on the cylinder. Apply a film
of engine oil to the cylinder head bolt threads and
washers, and hand tighten the bolts.
The following procedure must be used to torque the
cylinder head properly:
Cylinder Bolt Torque:
10mm - 46 ft. lbs. (62 Nm)
6mm - 6 ft. lbs. (8 Nm)
Torque all bolts evenly in a criss cross pattern
*Torque bolts to 22 ft. lbs. (30 Nm)
*Torque bolts to 51 ft. lbs. (70 Nm)
*Loosen bolts evenly 180
o
(1/2 turn)
*Loosen bolts again another 180
o
(1/2 turn)
*Torque bolts to 11 ft. lbs. (15 Nm)
*From this point, tighten bolts evenly 90
o

(1/4 turn)
*Finally, tighten another 90
o
(1/4 turn)
*Install two 6mm bolts and torque to 6 ft. lbs.

(8 Nm)