General Guidelines; Brake Fluid Replacement & Bleeding - Polaris IQ 2007 Service Manual

General Guidelines

WARNING
An unsafe condition exists when air is trapped in the
hydraulic 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. Without 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 inspection reveals spongy brakes.
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 vehicle until the failure in
the brake system is corrected.
Keep brake fluid tightly sealed and out of reach of
children. Brake fluid can accumulate moisture,
reducing it's effectiveness.
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.
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.
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
Final Drive and Brakes
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.
• 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
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