Polaris TRAIL BOSS 325 2001, Manual

Page: 83 / 296

ENGINE
3.27
VALVE SEAT RECONDITIONING, CONT.
1. Install pilot into valve guide.
2. Apply cutting oil to valve seat and cutter.
3. Place 46
q
cutter on the pilot and make a light cut.
4. Inspect the cut area of the seat.
S
If the contact area is less than 75% of the circum-
ference of the seat, rotate the pilot 180
q
and
make another light cut.
S
If the cutter now contacts the uncut portion of the
seat, check the pilot. Look for burrs, nicks, or
runout. If the pilot is bent it must be replaced.
S
If the contact area of the cutter is in the same
place, the valve guide is distorted from im-
proper installation and must be replaced. Be
sure the cylinder head is at the proper temper-
ature and replace the guide.
S
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 the amount of material
necessary to repair the seat surface.
5. 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
q
)
apply black permanent marker to the entire valve
face (A).
6. Insert valve into guide and tap valve lightly into place
a few times.
(A)