Snowmobile Polaris (2006 year). Manual - part 49

9.2

BRAKES

HYDRAULIC BRAKE SYSTEM

OVERVIEW

The Polaris snowmobile hydraulic brake system consists of 
the following components or assemblies: brake lever, master 
cylinder, hydraulic hose, brake caliper (slave cylinder), brake 
pads, and a brake disc which is secured to the drive line.

When the hand activated brake lever (A) is applied, it contacts 
a piston (B) within the master cylinder. As the master cylinder 
piston moves inward it closes a small opening called a 
compensating port (C) within the cylinder and starts to build 
pressure within the brake system. As the pressure within the 
system is increased, the pistons (D) located in the brake 
caliper move toward the disc and applies pressure to the 
moveable brake pads. As the lever pressure is increased, the 
braking effect is increased.

The friction applied to the brake pads will cause the pads to 
wear. As the pads wear, the piston within the caliper self-
adjusts and moves further outward.

Brake fluid level is critical to proper system operation. A low 
fluid level allows air to enter the system causing the brakes to 
feel spongy.

COMPENSATING PORT

Located within the master cylinder is a small compensating 
port (C) which is opened and closed by the master cylinder 
piston assembly. The port is open when the brake lever is 
released and the piston is outward. As the temperature within 
the hydraulic system changes, this port compensates for fluid 
expansion caused by heat, or contraction caused by cooling. 
During system service, be sure this port is open. Due to the 
high temperatures created within the system during heavy 
braking, it is very important that the master cylinder reservoir 
have adequate space to allow for the brake fluid to expand. 
Master cylinder reservoirs should be filled to the top of the 
fluid level mark on the inside of the reservoir, 1/4” - 5/16” (.6 
-.8 cm) below lip of reservoir opening.

This system also incorporates a diaphragm (E) as part of the 
cover gasket and a vent port (F) located between the gasket 
and the cover. The combination diaphragm and vent allow for 
the air above the fluid to equalize pressure as the fluid 
expands or contracts. Be sure the vent is open and allowed to 
function. If the reservoir is overfilled or the diaphragm vent is 
plugged, the expanding fluid may build pressure in the brake 
system and lead to brake failure.

GENERAL GUIDELINES

Keep these points in mind when bleeding hydraulic brakes:

• The master cylinder reservoirs have limited capacities. 

It is easy to empty them during the bleeding procedure. 
This introduces air into the system which you are trying 
to purge. Watch the reservoir closely and add fluid 
when necessary to prevent air from entering the system.

• Apply only light to moderate pressure to the lever or 

pedal when bleeding the brake system. Extreme 
pressure will cause a surge of fluid through the small 
orifices of the brake system when the bleeder screw is 
opened and introduce air into the system by means of 
cavitation.

WARNING

Contaminated brake discs or brake pads greatly reduce 

braking performance and increase stopping distance. 

Do not attempt to clean contaminated pads. Replace 

them. Clean the brake disc with brake cleaner.
This brake system requires ethylene-glycol based fluid 

(DOT 4). Do not use or mix different types of fluid such 

as silicone-based or petroleum-based.
Do not use brake fluid taken from old, used or unsealed 

containers. Never reuse brake fluid. 
Keep brake fluid tightly sealed and out of reach of chil-

dren. Brake fluid can accumulate moisture, reducing it's 

effectiveness.
A soft, spongy feeling in the brake lever and/or brake 

pedal could indicate a hazardous condition in the brake 

system. Do not operate the motorcycle until the failure 

in the brake system is corrected.
An unsafe condition exists when air is trapped in the hy-

draulic brake system. Air in the brake hydraulic system 

acts like a soft spring and absorbs a large percentage 

of the pressure developed by the master cylinder. With-

out this pressure, the braking system cannot develop 

full braking force to allow for safe, controlled stops. It is 

extremely important to bleed the brakes properly after 

any brake system work has been performed or when in-

spection reveals spongy brakes.

CAUTION

Pressure bleeding is not recommended. When fluid 

surges through the fittings, it is possible to cavitate the 

fluid and create air in the system. In addition, the fluid 

stored in a pressure bleeder may be contaminated. Al-

ways use fresh DOT 4 brake fluid from a sealed con-

tainer.

9.3

BRAKES

• Small amounts of air can become trapped in the banjo 

bolt fittings at the master cylinder(s) and junction points 
of brake lines. These fittings can be purged of air by 
following a standard bleeding procedure at these 
fittings (instead of the bleed screw on caliper) if 
necessary to speed the bleeding process. This is usually 
only needed if system was completely drained of fluid. 
Bleed each line connection, starting with the fitting 
closest to the master cylinder, working toward the 
caliper, and ending with the bleed screw. 

• Always torque banjo bolts and other brake system 

fittings to specified torque.

• Change fluid every 2 years, or when fluid is dark or 

contamination is suspected.

BRAKE FLUID REPLACEMENT & 
BLEEDING

This procedure should be used to change fluid or bleed brakes 
during regular maintenance, or after complete brake service. 
Brake fluid may damage painted or plastic surfaces. Take care 
not to spill, and wipe up any spills immediately. Cover parts to 
avoid damage.

1.

Clean the reservoir cover.

2.

Remove the two T-15 Torx screws from the cover.

3.

Carefully remove the cover and diaphragm assembly from
the reservoir.

4.

Under the cover, inspect the vent slots under the bellows
and remove any debris or blockage.

5.

Bleed or replace the fluid by attaching a clear hose from
the caliper bleeder fitting to a clean container. Be sure the
hose fits tightly on the bleeder fitting.

6.

Pump the brake lever a few times and hold.

7.

Slowly open the bleeder fitting and let the old fluid or air
escape. You will feel the lever release as you let the fluid
or air escape.

8.

Pump the brake lever a few times and hold it again.

9.

Repeat steps 7 and 8 until you see new brake fluid coming
from the caliper bleeder fitting or if you are bleeding the

air, repeat this step until you see only fluid coming out.
This may take several intervals.

10. Torque the bleeder screw to 8-11 ft-lb (11-15Nm).

11. When adding fluid, add DOT 4 brake fluid to 1/4-5/16”

(.6-.8 cm) from the reservoir top.

12. Install cover and diaphragm assembly.

13. Tighten the cover screws to 16-20 in-lb (1.8-2.3Nm).

14. Field test machine before putting into service. Check for

proper braking action and lever reserve. Lever reserve is
when the lever is firmly applied, the lever reserve should
be no less than 1/2” (1.3 cm) from the handlebar. See
“BRAKE LEVER TRAVEL” on page 3.14.

15. Verify that the sight glass indicates a full reservoir. 

16. Check brake system for any fluid leaks.

BRAKE LINE REPLACEMENT

Follow these steps if the brake line is to be replaced.

1.

If needed bleed the brake system by attaching a clear hose
to the caliper bleed fitting.

144-192 in-lb (16.2-21.6Nm)

brake light switch

9.4

BRAKES

2.

Attach the other end to a Mity Vac or similar vacuum tool.

3.

Bleed the system of brake fluid.

4.

Note the orientation of the brake line. The brake line will
need to be replaced in the same orientation.

5.

Remove the brake line from the caliper. Cap or cover the
end to catch any brake fluid that may still be in the line.

6.

Loosen the brake line from the master cylinder 1/4 to 1/2
turn.

7.

Remove the 4 screws that hold the master cylinder to the
handlebar. This will separate the master cylinder from the
switch pack.

8.

Unplug the brake light switch harness from the master
cylinder.

9.

Remove the brake line from the master cylinder.

10. Install new brake line on caliper and orientate it as noted

in step 4.

11. Torque the caliper banjo bolt to 168-216 in-lb (18.9-

24.4Nm).

12. Insert the new brake line and install into the master

cylinder. Torque the brake line to 144-192 in-lb (16.2-
21.6Nm).

13. Tighten the brake line into the master cylinder in an

orientation so that the line does not have any sharp bends
when it is installed on the handlebar.

14. Route the brake light switch in the harness correctly.

15. Place the switch pack with the master cylinder onto the

handle bar. Two smaller screws should be placed on the
top and the longest screw is placed on the lower right.

16. Follow the bleeding procedure as outlined in “BRAKE

FLUID REPLACEMENT & BLEEDING” on page 9.3.

BRAKE LIGHT SWITCH REPLACEMENT

1.

Remove the 4 screws that hold the master cylinder to the
handlebar. This will separate the master cylinder from the
switch pack.

2.

Unplug the brake light switch harness from the master
cylinder.

3.

Unplug the brake light switch from the master cylinder.

4.

Replace faulty brake light switch into the master cylinder
and route wires correctly.

5.

Plug the brake switch back into the harness.

6.

Replace the master cylinder to the switch pack and insert
the smaller screws on the top, the longest one goes into the
lower right side.

CALIPER

CALIPER REMOVAL

1.

Remove the two caliper bolts that hold the caliper to the
chaincase.

2.

Remove the caliper from the brake disc.

168-216in-lb(18.9-24.4Nm)

500 INDY, 340 Classic, 550 Classic, 340 Touring, Trail Touring,Trail Touring Deluxe 

9.5

BRAKES

CALIPER REPLACEMENT

The only serviceable item in the brake caliper is the brake 
pads. If any service is required of the caliper a new caliper is 
available.

1.

The brake line will need to go in the same orientation as it
was when it is replaced. Note the orientation of the brake
line before removing it. 

2.

Remove the banjo bolt from the brake line and tie up so
that all the brake fluid does not leak out.

3.

On a liquid cooled caliper, you will need to drain the
coolant from the coolant hoses. 

4.

Remove the two bolts (1) holding the caliper (2) to the
chaincase.

5.

Remove the caliper from the chaincase.

CALIPER ASSEMBLY

1.

Replace caliper bolts (1) and torque them to 18-20 ft-lb
(24-27Nm).

2.

On a liquid cooled caliper, hook up the coolant lines.

3.

Place the brake line on the caliper in the same orientation
as it was before it was removed.

4.

Clean the threads of the banjo bolt and the threads in the
caliper.

5.

Install banjo bolt into the caliper and torque it to 168-216
in-lb (18.9-24.4Nm).

6.

Bleed the brakes. See “BRAKE FLUID REPLACEMENT
& BLEEDING” on page 9.3.

7.

On a liquid cooled caliper you will need to bleed the
cooling system of any trapped air, See “COOLING
SYSTEM BLEEDING” on page 3.8.

BRAKE PAD REPLACEMENT

Brake pads need to be replaced if the total 
thickness of the pads and backing are less 
than.250” (6.35mm).

1.

Remove brake pad retaining pin (3).

2.

Remove the brake pads (4).

3.

Inspect the brake disc (5) for any wear. 

4.

Replace brake pads in reverse order of
removal.

BRAKE DISC REPLACEMENT

The brake disc should be replaced if the thickness of the disc is 
below .193”(.49cm).

1.

Remove the chaincase, see See “8.37 CHAINCASE
REMOVAL” on page 7.8..

2.

Slide the brake disc from the jackshaft.

3.

Check the jackshaft for any damage.

4.

Replace the o-ring on the jackshaft

5.

Replace the brake disk.

6.

Assemble the chaincase.

WIDETRAK BRAKE CALIPER

REMOVAL

1.

Remove brake cable.

2.

Remove retaining bolts, making note of location of hex
head bolt (with flat washer) and recessed Allen bolt.

NOTE:  Before performing next step, note position of 
two spring clips.

3.

Remove upper guide bushing and pads. Remove lower
guide bushing. Inspect pads and replace if worn beyond
service limit.

4.

With actuating arm facing up, carefully remove tension

1

2

3

4

Caliper

5

.250” (6.35mm)

Brake Pad