Polaris RANGER 500 2018 Service Manual page 150

ENGINE / COOLING SYSTEM
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°)
apply black permanent marker to the entire valve face
q
.
6. Insert valve into guide and tap valve lightly into place
a few times.
3.72
7. Remove valve and check where the Prussian Blue
indicates seat contact on the valve face. The valve
seat should contact the middle of the valve face or
slightly above, and must be the proper width.
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 all the way around the valve face
MEASUREMENT
Valve Seat Width:
Std.: .0591" (1.50 mm)
Service Limit: .0748" (1.90 mm)
Exhaust:
Std.: .0787" (2.00 mm)
Service Limit: .0945" (2.40 mm)
* If the indicated seat contact is at the top edge of the
valve face and contacts the margin area
high on the valve face. Use the 30° cutter to lower the
valve seat.
* If too low, use the 60° cutter to raise the seat. When
contact area is centered on the valve face, measure
seat width.
* If the seat is too wide or uneven, use both top and
bottom cutters to narrow the seat.
* If the seat is too narrow, widen using the 45° cutter
and re-check contact point on the valve face and seat
width after each cut.
9928485 R01 - 2017-2018 RANGER 500 / 570 Service Manual
NOTE
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Intake:
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