How to Bleed & Replace Brake Fluid on a 2018 Polaris Sportsman 570 EPS
Shop parts for a 2018 Polaris Sportsman 570 EPS ATV.
This MotoSport guide walks you through safely flushing and bleeding the brake system on a 2018 Polaris Sportsman 570 EPS. Procedures are written to be servicegrade and conservative for the MMY owner — follow every safety step and stop if anything feels wrong.
What you need
- DOT 4 brake fluid (do not use DOT 5 silicone)
- Clear vinyl tubing that fits snugly over bleed nipples
- Catch bottle with a oneway valve or a clean container and clean cap
- Proper open/box wrenches (bleeder nipples are usually 8mm-10mm)
- Brake clean, lintfree rags, disposable gloves, and safety glasses
- Floor jack, jack stands or a ramp rated for ATVs (sturdy support)
- Turkey baster or syringe for removing old fluid from reservoirs
- Assistant to pump and hold the brake lever/pedal (preferred)
Model notes for the 2018 Sportsman 570 EPS
- The Sportsman 570 EPS uses hydraulic disc brakes front and rear with an independent front and rear braking circuit (front master cylinder on the handlebar; rear master cylinder near the rear brake pedal/under the right fender area). Confirm exact reservoir locations before starting.
- The rear caliper on most Sportsman 570 units includes a mechanical parking brake linkage. Don't operate the parking brake while bleeding the hydraulic circuit; release it fully to avoid trapped pressure.
- Power steering (EPS) is an electrical/hydraulic assist system separate from the brakes — draining brake fluid will not affect EPS, but avoid contaminating EPS components with brake fluid.
- Use DOT 4 only. DOT 5 (silicone) is incompatible and will damage seals.
Safety first
- Work on a level surface. Secure the ATV on stands so wheels you're working on can spin freely.
- Brake fluid damages paint and plastics. Protect bodywork and immediately wipe spills with brake clean.
- Do not let reservoirs run dry during bleeding — you will introduce air into the system.
Preparation
- Park ATV, chock wheels, set parking brake, and remove the key.
- Remove wheel(s) or raise ATV so brake calipers and bleed nipples are accessible.
- Locate front master cylinder reservoir (handlebar) and rear reservoir (rear pedal area). Clean the reservoir caps before opening to avoid contamination.
- Siphon out old fluid from each reservoir with a turkey baster until level is low but not empty. Dispose of old fluid properly.
- Top each reservoir with fresh DOT 4 fluid to the MAX line. Keep caps loosely on or recap lightly to limit contamination while allowing venting.
Bleeding strategy
The Sportsman 570 uses separate front and rear circuits. Bleed each circuit independently. For each circuit, start with the caliper furthest from that circuit's master cylinder and proceed to the closest.
Typical bleed sequence
- Front circuit: right front caliper → left front caliper (if dual front calipers).
- Rear circuit: if only one rear caliper, bleed that caliper only. If a linked rear system has two outlets, start with the furthest from the rear master cylinder.
Bleeding steps (per circuit)
- Attach clear tubing to the bleed nipple and place the other end into the catch bottle partially filled with a little clean brake fluid to avoid sucking air back in.
- Have an assistant slowly depress the brake lever or pedal to build moderate pressure and hold it down.
- With the lever/pedal held, use the correct wrench to open the bleed nipple about a quarter turn. Fluid and air should flow into the tube. Tighten the nipple before the assistant releases the lever/pedal to prevent drawing air back in.
- Repeat the pump/open/release cycle until you see only clear, bubblefree fluid coming out and the reservoir level remains stable. Keep reservoir topped to prevent it going below the MIN line.
- When no air is visible, tighten the bleed nipple to the recommended torque (handtight plus a quarter turn is typical; avoid overtorqueing). Wipe nipple and move to next caliper in sequence.
- After finishing the circuit, top the reservoir to the MAX line, cap it securely, and test the lever/pedal for firmness before moving on to the next circuit.
Full fluid replacement (flush)
To fully replace old fluid, repeatedly draw out old fluid from the reservoir and refill with fresh fluid before bleeding each circuit. Continue bleeding until the expelled fluid is the same clear color and free of contamination.
Postbleed checks
- Ensure all bleed nipples are tightened and capped if applicable. Clean any spilled fluid.
- Verify reservoir levels at MAX. Reinstall reservoir caps and any removed body panels/wheels.
- Lower the ATV, start it (if needed for parking brake release) and carefully test brakes in a safe area at low speed. Expect a firmer lever/pedal once air is cleared.
- If lever/pedal feels spongy, rebleed the suspect circuit. Don't ride until brakes are firm and reliable.
Troubleshooting
- Persistent sponginess: look for remaining air entry points, cracked hoses, leaking caliper seals, or a failing master cylinder.
- Leaking around bleeder nipple: replace nipple or caliper bleeder screw and clean mating surfaces.
- Brake fluid contamination: brown/black fluid indicates moisture/contaminants — flush entire system and replace hoses if contaminated.
Maintenance tips & owner notes
- Brake fluid absorbs moisture over time. Replace fluid every 1-2 years, sooner if you ride in wet/salty conditions.
- Keep spare DOT 4 fluid in a sealed container. Once opened, expose it to air only briefly because it absorbs moisture.
- Inspect brake pads and rotor condition while wheels are off. The Sportsman 570 EPS is often used in heavy work & trail conditions — pads can wear faster under load.
- Because the rear has a mechanical parking brake linkage, periodically inspect and lubricate pivot points to ensure free movement and correct parking brake release during bleeding.
If you prefer professional service or encounter leaking master cylinders, caliper damage, or a suspected internal master cylinder failure, have a qualified technician perform repairs.
Related Shopping Categories
Shop Brake Fluid for a 2018 Polaris Sportsman 570 EPS ATV.
Shop Brake Bleeders for a 2018 Polaris Sportsman 570 EPS ATV.
Shop Brake Pads for a 2018 Polaris Sportsman 570 EPS ATV.
Shop Brake Lines for a 2018 Polaris Sportsman 570 EPS ATV.
Shop Brake Tools for a 2018 Polaris Sportsman 570 EPS ATV.
Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.