Polaris 850 PRO-RMK 155 2.6" QD 2021, Manual

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9850060 R02 - 2020-2021 850 AXYS™ Long Track Snowmobile Service Manual
© Copyright Polaris Inc.
BRAKE CALIPER PISTON / SEAL
REPLACEMENT
WARNING
NEVER RE-USE PISTON SEALS. ALWAYS REPLACE
WITH NEW PARTS.DO NOT ATTEMPT TO SAND OR
POLISH A CALIPER PISTON.
IMPORTANT
Keep brake fluid away from painted surfaces.
1. Remove the banjo bolt and brake hose from the
brake caliper. Drain the brake fluid into a jar or
suitable container.
2. Discard the two crush washers.
3. Remove the brake pad retaining pin and brake pads
e
.
4. Hold the caliper over a jar or suitable container and
then push the pistons back into the caliper. This will
push the brake fluid inside the caliper out of the banjo
fitting hole.
WARNING
NEVER RE-USE BRAKE FLUID. USED BRAKE FLUID
MAY CONTAIN AIR BUBBLES.ALWAYS USE NEW
BRAKE FLUID FROM AN UNOPENED CONTAINER.
5. Clamp the end of a 1/4″ thick, 2″ x 10″ piece of steel
or wood to a workbench. Allow the piece of steel or
wood to hang off the bench by 4″ to 5″.
6. Position the caliper over the piece of steel or wood
with the piece firmly against one of the retraced
pistons.
IMPORTANT
DO NOT PUSH ON THE CALIBER BORE PLUG
y
.
DOING SO WILL BREAK THE PLUG SEAL AND
REQUIRE CALIPER REPLACEMENT.
CAUTION
TO AVOID POSSIBLE INJURY, DO NOT PLACE
FINGERS BETWEEN PISTONS TO ATTEMPT TO
CATCH THEM WHEN APPLYING COMPRESSED AIR.
WEAR EYE PROTECTION WHEN APPLYING
COMPRESSED AIR TO CALIPER.
7. Insert a rubber-tipped air nozzle into the brake hose
inlet port and apply compressed air to push out the
piston
q
.
8. To remove the second piston, lay a rubber sheet on
the steel plate and position the caliper over the rubber
sheet to seal the open piston bore. Repeat step 7.
9. Using a plastic or wood pick, remove the piston seals
w
from the caliper bores. Discard the seals.
10. Clean the caliper and pistons with denatured alcohol
and dry with either compressed air or a lint-free rag.
11. Inspect the caliper bores and pistons for pitting,
heavy scoring or corrosion. Replace parts if heavily
scored or pitted.
12. To assemble the caliper, lubricate two new piston
seals with new brake fluid. Install each seal by
inserting one point of the seal into the bore groove,
and then work the seal around the groove with your
index finger. Do not twist, or rip the seals.
13. Coat the piston thoroughly with new brake fluid.
Evenly insert each piston into the bores, working
each in by hand carefully and slowly. Push each
piston down until bottomed out.
14. Reinstall the brake caliper on to the chaincase or
QuickDrive. Torque to specification.
TORQUE
Brake Caliper Mounting Bolts:
18.4 ft-lbs (25 Nm)
15. Inspect both brake pads prior to installation. If they
are within the pad wear specification, reinstall into
caliper.
FINAL DRIVE / BRAKE SYSTEMS