Polaris A12MH46AX Service Manual page 82

7. Place a new guide in the valve guide installation tool
and press guide in to proper depth. Check height of
each guide above the cylinder head (A).
Valve Guide Installed Height
Valve Guide Height:
.689 - .709" (17.5 - 18.0 mm)
NOTE: The guide can also be driven in to the proper
depth. Inspect the guide closely for cracks or
damage if a driver is used.
Reaming The Valve Guide
8. Allow cylinder head to cool to room temperature.
Apply cutting oil to the reamer. Guides should be
reamed from the valve spring side of the cylinder
head. Ream each guide to size by turning the reamer
clockwise continually.
clockwise during removal of the tool.
9. Clean guides thoroughly with hot soapy water and a
nylon brush. Rinse and dry with compressed air.
Apply clean engine oil to guides.
10. Install pilot into valve guide.
11. Apply cutting oil to valve seat and cutter.
Continue to rotate reamer
9923412 - 2012 Sportsman 400/500 and EFI Tractor Service Manual
© Copyright 2011 Polaris Sales Inc.
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12. Place 46 cutter on the pilot and make a light cut.
13. Inspect the cut area of the seat.
• If the contact area is less than 75% of the
circumference of the seat, rotate the pilot 180
make another light cut.
• If the cutter now contacts the uncut portion of the
seat, check the pilot.
runout. If the pilot is bent it must be replaced.
• If the contact area of the cutter is in the same
place, the valve guide is distorted from improper
installation and must be replaced. Be sure the
cylinder head is at the proper temperature and
replace the guide.
• If the contact area of the initial cut is greater than
75%, continue to cut the seat until all pits are
removed and a new seat surface is evident.
NOTE: Remove only
necessary to repair the seat surface.
14. To check the contact area of the seat on the valve
face, apply a thin coating of Prussian Blue™ paste to
the valve seat. If using an interference angle (46
apply black permanent marker to the entire valve face
(A).
15. Insert valve into guide and tap valve lightly into place
a few times.
ENGINE
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Look for burrs, nicks, or
the amount of material
A
3.27
3
and
o
)