Cylinder Head Assembly - Polaris PREDATOR 50 2009 Manual

NOTE: When using an interference angle, the seat
contact point on the valve will be very narrow, and is
a normal condition.
continuous contact point on the black marker, all the
way around the valve face.
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
passages thoroughly.
13. Spray electrical contact cleaner into oil passages and dry
using compressed air.
Look for an even and
Seat
Width
ENGINE / TRANSMISSION

Cylinder Head Assembly

CAUTION
Wear eye and face 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 assembly lubricant or a mixture of
motor oil and molybdenum disulfide grease.
4. Install valve carefully with a rotating motion to avoid
damaging valve seal.
5. Dip valve spring and retainer in clean engine oil and install
spring with closely spaced coils toward the cylinder head.
Closely spaced
coils toward
cylinder head
6. Place retainer on springs and install spring compressor.
Compress spring only enough to allow split keeper
installation and prevent loss of spring tension. Install split
keepers with the gap even on both sides. Repeat procedure
for remaining valve
7. When all valves are installed, tap lightly with a flat punch
on end of valve stem to seat split keepers. DO NOT tap on
top retainer or keepers may dislodge!
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