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9850068 R01 - 2020-2021 RZR PRO XP / XP 4 Service Manual
© Copyright Polaris Industries Inc.
3.75
PISTON RING REMOVAL
1. Carefully remove top compression ring
q
by hand or
using a ring removal pliers.
• Piston ring pliers: Carefully expand ring and lift it off
the piston.
• By hand: Placing both thumbs on the ring ends,
spread the ring open and push up on opposite side. Do
not scratch ring lands.
CAUTION
DO NOT expand the ring more than necessary to
remove it from the piston or the ring may break or lose
radial tension.
2. Repeat procedure for second compression ring
w
.
3. The oil control ring
e
is a three piece design
consisting of a top and bottom steel rail and a center
expander section. Remove top rail first, then bottom
rail, then the expander.
PISTON RING TO GROOVE CLEARANCE
Measure piston ring to groove clearance
q
by placing
the ring in the ring land and measuring with a thickness
(feeler) gauge. Replace piston and rings if ring-to-groove
clearance exceeds service limits.
MEASUREMENT
Piston Ring to Groove Clearance:
Top Ring/ Second Ring:
.0007 - .0023" (0.020 - 0.060 mm)
Service Limit:.0047" (0.12 mm)
PISTON RING INSTALLED GAP
1. Place each piston ring
q
inside the cylinder
w
. Use
the piston to push the ring squarely into cylinder.
2. Measure installed gap with a feeler gauge
e
at both
the top and bottom of the cylinder.
NOTICE
A difference between top and bottom end gap
measurements is a general indication of cylinder taper
(wear). The cylinder should be measured for taper and
out of round.
ENGINE / COOLING SYSTEM