How to Bleed and Replace Brake Fluid on a 2014 Polaris Sportsman 400 H.O. 4X4

Shop parts for a 2014 Polaris Sportsman 400 H.O. 4X4 ATV.

This MotoSport guide walks you step by step through replacing and bleeding the brake fluid on a 2014 Polaris Sportsman 400 H.O. 4X4. Follow safety precautions, use the correct fluid, and keep the reservoir filled during the job to avoid air contamination. If you prefer, MotoSport carries the parts and tools needed for this service.

What you need

  • DOT 4 brake fluid (Polaris specifies DOT 4; do NOT use mineral oil)
  • Clear tubing that fits the bleeder nipples
  • Catch bottle marked for used brake fluid
  • Wrench set sized to bleeder nipples and caliper hardware
  • Brake bleeder kit or vacuum pump (optional, but speeds the job)
  • Clean rags, gloves, safety glasses
  • Jack or stands to safely elevate the ATV if needed
  • Torque wrench (recommended for caliper/banjo bolts)

Model notes — 2014 Polaris Sportsman 400 H.O. 4X4

  • The Sportsman 400 H.O. uses DOT 4 hydraulic brake fluid in its front and rear systems. Do not substitute DOT 3/5.1 unless specified by Polaris; DOT 4 gives higher boiling point and OEM compatibility.
  • This model typically has separate front and rear master cylinder reservoirs. Work one circuit at a time to avoid mixing or overfilling.
  • There is no traction control ABS module on this basic 400 H.O.; bleeding is limited to calipers, lines, and master cylinder. If your unit has aftermarket or accessory systems, consult those component manuals before bleeding.
  • Inspect banjo bolts, copper crush washers, caliper pistons, and lines for leaks, swelling, or damage. Replace any suspect hardware before bleeding.
  • Brake lever free-play adjustment and parking brake operation should be checked after bleeding and before riding.

Preparation

  • Park on level ground, engage parking brake, and isolate the ignition.
  • Clean the area around the master cylinder reservoir caps to prevent contaminants from entering the system when opened.
  • Remove the cap(s) and diaphragm(s) from the reservoir(s). Cover the opening with a clean rag to keep dirt out while you position tools.
  • Elevate whichever wheel(s) you will bleed first so you can move caliper pistons easily. Secure the ATV with jack stands or ramps rated for off-road vehicles.

Drain and replace brake fluid (full replacement)

  1. Use a turkey-baster or syringe to remove most of the old fluid from the reservoir(s). Dispose of old fluid per local regulations — it absorbs moisture and degrades performance.
  2. Fill the reservoir with fresh DOT 4 fluid to the recommended level. Replace the cap loosely to minimize contamination while you work.

Bleeding methods (choose one)

Two-person pump method

  1. One person pumps the brake lever/pedal slowly to build pressure, then holds it compressed.
  2. The second person cracks the bleeder nipple on the caliper until fluid (not air) flows, then tightens the nipple while the lever/pedal remains held.
  3. The first person releases the lever/pedal and repeats. Keep reservoir topped up between cycles.
  4. Continue until clear fluid with no air bubbles flows and lever feel is firm.

Gravity bleed (slow but simple)

  1. Attach clear tubing to the bleeder nipple and route to a catch bottle below the caliper.
  2. Open the bleeder and allow fluid to flow slowly until clear fluid emerges. Watch for bubbles; if present, allow more time or use another method.
  3. Close the bleeder and top off reservoir when finished.

Vacuum pump or pressure bleeder (recommended for one-person efficiency)

  1. Attach vacuum pump to the bleeder nipple and draw fluid until clear fluid flows without bubbles.
  2. If using a pressure bleeder on the reservoir, pressurize to the recommended low pressure and open bleeders one at a time until clear fluid exits, then close each bleeder.

Bleeding sequence for Sportsman 400 H.O.

Work from the wheel farthest from the master cylinder toward the closest. Typical sequence: rear passenger/left rear – rear driver/right rear – front passenger/right front – front driver/left front. If your ATV has separate front and rear circuits, bleed the rear circuit fully, then the front circuit.

Detailed bleed steps

  1. Start with the highest/most remote caliper. Fit clear tubing onto the bleeder nipple and submerge the other end in clean fluid in a catch bottle to prevent air re-entry.
  2. Have an assistant pump and hold the lever/pedal, or use a vacuum pump. Open the bleeder just enough to allow fluid flow. Close before release if using the pump-and-hold method.
  3. Monitor the reservoir and refill as needed to prevent it running dry.
  4. Repeat cycles until no air bubbles appear in the tubing and lever feel is consistent and firm.
  5. Tighten the bleeder nipple to snug, wipe away spilled fluid, and move to the next caliper.
  6. When all wheels are bled, top the reservoir to the specified level and reinstall the cap and diaphragm.

Post-bleed checks

  • Check lever/pedal firmness at rest and during a slow brake test on the stand. The lever should not feel spongy.
  • Inspect all fittings, banjo bolts, and bleeder nipples for leaks. Re-torque caliper hardware if removed, using a torque wrench where possible.
  • Cycle the brakes several times with the ATV on the ground; test at low speed in a safe area to confirm braking performance before regular use.
  • Dispose of used brake fluid responsibly. Keep DOT fluids sealed and away from painted surfaces — they damage paint and plastics.

Common issues & troubleshooting

  • Persistent spongy brake feel: repeat bleeding, ensure lines and caliper pistons move freely, and check for master cylinder internal leakage.
  • Air keeps returning after a good bleed: inspect for leaks at hose connections, banjo fittings, or cracked hoses; replace suspect lines.
  • Brake lever bottoms out with pressure: inspect master cylinder and calipers for worn seals or damaged pistons; overhaul or replace components as needed.

Maintenance tips specific to this model

  • Check brake fluid annually for contamination and moisture. Replace every 1-2 years if used frequently in wet/muddy conditions.
  • After heavy trail use or water crossings, inspect caliper boots and piston seals for ingress of dirt or water; clean and reseal as necessary.
  • Keep a set of spare crush washers and bleeder caps in your tool kit; they're inexpensive and prevent leaks during reassembly.

Following this MotoSport procedure will restore proper brake feel and help maintain safe, reliable stopping performance on your 2014 Polaris Sportsman 400 H.O. 4X4. If you encounter complex leaks, master cylinder failure, or uncertain components, contact a qualified technician or consult MotoSport for replacement parts and support.

Related Shopping Categories

Shop Brake Fluid for a 2014 Polaris Sportsman 400 H.O. 4X4 ATV.

Shop Brake Bleeders for a 2014 Polaris Sportsman 400 H.O. 4X4 ATV.

Shop Brake Pads for a 2014 Polaris Sportsman 400 H.O. 4X4 ATV.

Shop Brake Lines for a 2014 Polaris Sportsman 400 H.O. 4X4 ATV.

Shop Brake Tools for a 2014 Polaris Sportsman 400 H.O. 4X4 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.