BRAKE NOISE TROUBLESHOOTING
Dirt or dust buildup on the brake pads and disc is the most common cause of brake noise (squeal caused by vibration).
If cleaning does not reduce the occurrence of brake noise, Permatex™ Disc Brake Quiet can be applied to the back of
the pads. Follow directions on the package. This will keep pads in contact with caliper piston(s) to reduce the chance
of squeaks caused by dirt or dust.
Dirt, dust, or imbedded material on pads or disc
Pad(s) dragging on disc due to:
Master cylinder reservoir overfilled
Master cylinder compensating port restricted
Master cylinder piston not returning completely
Caliper piston(s) not returning
Operator error (riding the brake)
Loose wheel hub or bearings
Brake disc warped or excessively worn
Brake disc misaligned or loose
Noise is from other source (axle, hub, disc or wheel)
HYDRAULIC BRAKE SYSTEM OPERATION
The Polaris brake system consists of the following components or assemblies: brake pedal, master cylinder, hydraulic
brake lines, brake calipers, brake pads, and brake discs, which are secured to the drive line.
When the foot activated brake lever is applied it applies pressure on the piston within the master cylinder. As the
master cylinder piston moves inward it closes a small opening (compensating port) within the cylinder and starts to
build pressure within the brake system. As the pressure within the system is increased, the pistons located in the brake
calipers move outward and apply pressure to the moveable brake pads. These pads contact the brake discs and move
the calipers in their floating bracket, pulling the stationary side pads into the brake discs. The resulting friction reduces
brake disc and vehicle speed.
The friction applied to the brake pads will cause the pads to wear. As these pads wear, the piston within the caliper
moves further outward and becomes self adjusting. Fluid from the reservoir fills the additional area created when the
caliper piston moves outward.
Brake fluid level is critical to proper system operation. Too little fluid will allow air to enter the system and cause the
brakes to feel spongy. Too much fluid could cause brakes to drag due to fluid expansion.
Located within the master cylinder is the compensating port which is opened and closed by the master cylinder piston
assembly. As the temperature within the hydraulic system changes, this port compensates for fluid expansion or
contraction. 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 fluid expansion. Never overfill the reservoir! Do not fill
the reservoir beyond the MAX LEVEL line!
When servicing Polaris brake systems use only Polaris DOT 4 Brake Fluid (PN 2872189).
WARNING: Once a bottle is opened, use what is necessary and discard the rest in accordance with local laws.
Do not store or use a partial bottle of brake fluid. Brake fluid is hygroscopic, meaning it rapidly absorbs
moisture. This causes the boiling temperature of the brake fluid to drop, which can lead to early brake fade
and the possibility of serious injury.
9925724 R01 - 2014-2015 RZR XP 1000 / RZR XP4 1000 Service Manual
Brake Noise Troubleshooting
Spray disc and pads with CRC Brakleen™ or an
equivalent non-flammable aerosol brake cleaner.
Remove pads and/or disc hub to clean imbedded
material from disc or pads.
Adjust pad stop (front calipers)
Set to proper level
Clean compensating port
Inspect. Repair as necessary
Clean piston(s) seal
Check wheel and hub for abnormal movement.
Inspect and repair as necessary
If noise does not change when brake is applied check
other sources. Inspect and repair as necessary
© Copyright 2014 Polaris Industries Inc.