Cylinder Head Assembly - Polaris 2009 Trail Boss 330 Service Manual

NOTE: When using an interference angle, the seat
contact point on the valve will be very narrow, and is
a normal condition. Look for an even and continuous
contact point on the black marker, all the way around
the valve face.
Valve Seat Width:
Intake Std: .039I (1.0 mm)
Limit: .055I (1.4 mm)
Exhaust Std: .059I (1.4 mm)
Limit: .071I (1.8 mm)
8. Clean all filings from the area with hot soapy
water, rinse, and dry with compressed air.
9. Lubricate the valve guides with clean engine oil,
and apply oil or water based lapping compound to
the face of the valve. Lapping is not required with
an interference angle.
10. Insert the valve into its respective guide and lap
using a lapping tool or a section of fuel line
connected to the valve stem.
11. Rotate the valve rapidly back and forth until the
cut sounds smooth. Lift the valve slightly off of the
seat, rotate 1/4 turn, and repeat the lapping
process. Do this four to five times until the valve is
fully seated, and repeat process for the other
valve.
12. Clean cylinder head, valves, and camshaft oil
supply passage (A) thoroughly.
Seat
Width
13. Spray electrical contact cleaner into oil passage
and dry using compressed air.

CYLINDER HEAD ASSEMBLY

CAUTION: Wear eye protection during assembly.
NOTE: Assemble the valves one at a time to maintain
proper order.
1. Install new valve seals on valve guides.
2. Apply engine oil to valve guides and seats.
3. Coat valve stem with molybdenum disulfide
grease.
4. Install valve carefully with a rotating motion to
avoid damaging valve seal.
ENGINE
A
3.21