How to Bleed & Replace Brake Fluid on a 2009 Yamaha Wolverine 350
Shop parts for a 2009 YAMAHA WOLV350 ATV.
This procedure covers safely draining old brake fluid, flushing the lines, and bleeding the brake system on a 2009 Yamaha Wolverine 350 (MMY). Follow every step carefully and use proper safety gear. If you are unsure at any point, stop & consult a qualified technician.
What you need
- DOT 4 brake fluid (Yamaha recommends DOT 4 for most models; confirm with your owner's manual)
- Clear 1/4" vinyl tubing
- Bleeder bottle or clear container
- Wrenches for bleeder nipples (usually 8mm or 10mm)
- Phillips & flat screwdrivers
- Turkey baster or fluid syringe
- Shop rags & brake parts cleaner
- Jack or stands to lift the ATV safely
- Disposable gloves & eye protection
- Torque wrench (for reassembly where applicable)
Model notes for the 2009 Yamaha Wolverine 350 (MMY)
- The Wolverine 350 uses conventional hydraulic brakes without antilock systems — bleeding is manual and straightforward.
- Front master cylinder is on the right handlebar; rear master cylinder is mounted near the foot pedal area or frame. Reservoir locations vary slightly by year & configuration, so visually confirm before starting.
- The system typically uses DOT 4 fluid. Do not mix DOT 3, DOT 4, and DOT 5 (silicone) fluids; DOT 5 is not compatible with systems designed for glycol-based fluids.
- Check rubber hoses, banjo fittings, and caliper pistons for corrosion, leaks, or soft/swollen hose sections while you have the system open.
- If pads or rotors are contaminated with old fluid, replace or service them before finishing the job.
Safety prep
- Work on a level surface with the engine off and key removed.
- Stabilize the ATV on jack stands so wheels can rotate freely as you bleed each caliper.
- Protect painted surfaces from brake fluid; fresh fluid will damage paint. Use rags or tape around reservoirs & fittings.
Step-by-step bleed & fluid replacement
- Locate reservoirs: remove seat or panels if needed. Clean around caps to prevent contamination. Open caps – do not remove reservoirs from master cylinders.
- Remove as much old fluid from each reservoir as possible using a turkey baster or syringe. Catch waste fluid in a waste container for proper disposal.
- Top reservoirs with a small amount of fresh DOT 4 fluid to prevent ingress of air while you work.
- Begin at the brake caliper farthest from the master cylinder. For most Wolverines this means: rear caliper first, then front calipers left/right accordingly. If uncertain, follow the master-to-farthest rule.
- Fit clear tubing over the caliper bleeder nipple and place the other end into a catch bottle partially filled with fresh fluid to avoid sucking air back in.
- Have an assistant slowly apply the brake lever or pedal several times and hold it down. Open the bleeder nipple about a 1/4 turn to let fluid & air escape. Close nipple before the lever/pedal is released. Repeat until you see clear fluid with no air bubbles exiting.
- Keep the reservoir level topped with fresh fluid throughout so air cannot enter the system.
- Move to the next caliper — always work from the farthest caliper toward the master cylinder.
- Once all calipers are bled and fluid runs clear, fill reservoirs to the proper level, reinstall caps, and clean all fittings and spilled fluid.
- Pump the brake lever & pedal with the engine off to check for firm feel. If soft or spongy, repeat bleeding steps until firm.
- After confirming firm brakes, torque any removed bolts to factory specs where applicable, lower the ATV, and test brakes at low speed in a safe area.
Additional checks & maintenance tips
- Inspect pad thickness, rotor surface, and caliper slide movement. Replace pads if less than manufacturer minimum thickness.
- Check all banjo bolts, crush washers, and hose clamps for leaks. Replace crush washers whenever a banjo fitting is removed.
- Replace brake fluid every 1-2 years or sooner if you see moisture contamination or dark fluid. Moisture in fluid reduces boiling point & brake performance.
- Dispose of old brake fluid per local hazardous-waste rules. Do not pour down drains.
Troubleshooting
- Persistent soft pedal after proper bleeding: check for internal master cylinder leaks or collapsed hoses.
- Visible air bubbles immediately after filling reservoir: a leak on the suction side or a cracked hose may be drawing air; pressure-test lines.
- Brake drag after bleeding: caliper pistons may be sticking or retracted pins corroded — clean, lubricate with recommended caliper grease or service calipers.
Perform a cautious road test in a safe area to confirm braking performance before normal riding. If brakes feel marginal or you find questionable components, replace parts with OEM-quality replacements available from MotoSport or consult a professional technician.
Related Shopping Categories
Shop Brake Fluid for a 2009 YAMAHA WOLV350 ATV.
Shop Brake Bleeders for a 2009 YAMAHA WOLV350 ATV.
Shop Brake Pads for a 2009 YAMAHA WOLV350 ATV.
Shop Brake Lines for a 2009 YAMAHA WOLV350 ATV.
Shop Brake Tools for a 2009 YAMAHA WOLV350 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.