Service Manual

3.29
ENGINE
3
Combustion Chamber
1. Clean all accumulated carbon deposits from combustion
chamber and valve seat area with carbon cleaner and a soft
plastic scraper.
IMPORTANT: Do not use a wire brush, metal scraper,
or abrasive cleaners to clean the bottom of the
cylinder head. Extensive damage to the cylinder head
may result. Wear safety glasses during cleaning.
Valve Seat Reconditioning
NOTE: Polaris recommends that the work be done
by a local machine shop that specializes in this area.
NOTE: The cylinder head valve guides cannot be
replaced.
Valve Seat Inspection
Inspect valve seat in cylinder head for pitting, burnt spots,
roughness, and uneven surface. If any of the above conditions
exist, the valve seat must be reconditioned. If the valve seat is
cracked the cylinder head must be replaced.
Follow the manufacturers instructions provided with the valve
seat cutters in the Cylinder Head Reconditioning Kit (PN
2200634). Abrasive stone seat reconditioning equipment can
also be used. Keep all valves in order with their respective seat.
NOTE: Valve seat width and point of contact on the
valve face is very important for proper sealing. The
valve must contact the valve seat over the entire
circumference of the seat, and the seat must be the
proper width all the way around. If the seat is
uneven, compression leakage will result. If the seat
is too wide, seat pressure is reduced, causing
carbon accumulation and possible compression
loss. If the seat is too narrow, heat transfer from
valve to seat is reduced. The valve may overheat
and warp, resulting in burnt valves.
1. Install pilot into valve guide.
2. Apply cutting oil to valve seat and cutter.
3. Place 46
° cutter on the pilot and make a light cut.
WARNING
Wear eye protection or a face shield during
cylinder head disassembly and reassembly.
Combustion Area