How to bleed and replace brake fluid on a 2017 Polaris Sportsman Touring 570 ATV

Overview

This MotoSport guide walks you through flushing and bleeding the brake system on a 2017 Polaris Sportsman Touring 570 (MMY). Follow safety precautions, use the correct fluid, and work methodically to avoid air in the lines. The procedure below is written for the factory hydraulic system used on the Sportsman Touring 570.

Safety & prep

• Work on a level surface, engine off, parking brake set, and keys removed.
• Wear safety glasses and nitrile gloves. Brake fluid is corrosive to paint and plastics.
• Use DOT 4 brake fluid (Polaris recommends DOT 4 for this model); keep the bottle sealed until use.
• Have rags, a clear catch bottle and hose, a wrench for the bleed nipples, and a fluid transfer or pressure-bleeder tool ready.
• Clean around the master cylinder reservoir cap before opening to prevent contamination.
• Dispose of old fluid properly; do not reuse.

Model notes specific to the 2017 Sportsman Touring 570

• The Sportsman Touring 570 uses a single hydraulic system with a master reservoir accessible near the handlebar area. Keep the reservoir upright and level while topping up.
• This model typically does not have an ABS module; bleeding is performed at each caliper bleed nipple. If your unit is fitted with an option or aftermarket ABS, refer to system-specific procedures before bleeding.
• There are multiple calipers (front & rear). Use the standard sequence: furthest caliper from the master cylinder first, ending with the nearest.
• Brake hoses and fittings on this ATV are designed for DOT fluid only. Do not introduce mineral-oil systems or adapters.

Tools & materials

• DOT 4 brake fluid (new, unopened)
• Clear tubing and a catch bottle
• 8mm or appropriate-size wrench for bleed nipples (verify size on your calipers)
• Turkey baster or fluid syringe for reservoir removal
• Brake bleeder kit or hand pump (optional but speeds the job)
• Rags, isopropyl alcohol for cleanup, jack or ramps if needed

Step-by-step: drain, replace & bleed

1. Clean the reservoir cap area thoroughly. Remove the cap and diaphragm, noting orientation. Siphon out most old fluid with a turkey baster or syringe until the reservoir is nearly empty.
2. Top the reservoir with fresh DOT 4 fluid to the fill mark. Keep the reservoir capped loosely so you can monitor level during bleeding.
3. If you have a helper: position them at the handlebars to operate the brake lever/pedal. If alone, use a pressure bleeder or one-way bleeder kit.
4. Identify bleed sequence. On the Sportsman Touring 570 use: 1) furthest caliper from master cylinder, 2) next furthest, 3) front calipers, finishing at the caliper closest to the master cylinder. When in doubt, pick the caliper that is longest hydraulic line run first.
5. Attach clear tubing to the first bleed nipple and place the other end in a catch bottle partially filled with clean brake fluid to prevent air re-entry.
6. Have your helper slowly squeeze the brake lever/pedal several times and hold it down. Open the bleed nipple (about a 1/4 turn) to allow fluid and air to escape, then close the nipple before the lever/pedal is released. Repeat until the fluid leaving the hose is clean and bubble-free.
7. Keep the reservoir topped frequently during the process to prevent drawing air into the master cylinder. Never let the reservoir run dry.
8. Repeat steps 5-7 for each caliper following the bleed sequence. Use fresh tubing or flush tubing between calipers if it becomes contaminated with debris.
9. When all calipers are clear and the reservoir is at the correct level, tighten all bleed nipples to proper snugness. Wipe down fittings and clean any spilled fluid immediately.
10. Reinstall the reservoir diaphragm and cap. Test the brake lever/pedal for firm, consistent pressure with the ATV stationary. If sponginess remains, rebleed the caliper sequence until firm.
11. Road/test ride gently at low speed to ensure full braking performance. Recheck fluid level after the test and inspect for leaks.

Troubleshooting & tips

• If repeated bleeding does not firm the lever, inspect for leaks, collapsed hoses, or a leaking master cylinder. Replace compromised parts before continuing.
• Use short, firm pump strokes during manual bleeding; long slow strokes can introduce air back into the reservoir.
• Label the reservoir cap and diaphragm orientation if you remove them to ensure proper reseating.
• If the fluid appears dark or contaminated repeatedly, inspect caliper seals and pistons for deterioration; contaminated systems can indicate component failure.

Maintenance interval

MotoSport recommends replacing brake fluid every 12 to 24 months depending on riding conditions. If you ride in wet or extreme conditions, inspect and replace fluid annually to prevent moisture buildup and corrosion.

Final checks

• Confirm no leaks at calipers, lines, or master cylinder.
• Confirm brake lever/pedal is firm and returns to rest smoothly.
• Dispose of old fluid according to local hazardous-waste rules.