Use a brake bleeder kit by filling the reservoir with fresh fluid and bleeding from the wheel farthest from the master cylinder.
For the full breakdown, see our best 1 Person Brake Bleeder Kit guide.
Air trapped in the brake lines turns a firm pedal spongy and stretches stopping distances. Knowing how to use a brake bleeder kit comes down to three things: fresh fluid, the right wheel order, and never letting the master cylinder run dry. Done properly, the whole job takes about an hour.
What A Brake Bleeder Kit Does
A brake bleeder kit pushes old fluid and trapped air out of the hydraulic system and pulls fresh fluid in behind it. The hose connects to the bleeder screw on each caliper or wheel cylinder, and escaping air shows up as bubbles in the clear tube. The procedure applies to hydraulic disc and drum brakes that use a fluid reservoir and bleeder screws.
The three common styles are vacuum bleeders, pressure bleeders, and pedal-pump manual kits. All three work on the same principle, but each moves fluid differently and each has its own rule for turning the bleeder screw.
How Do You Bleed Brakes With A Kit?
The routine is the same for most kits: fill the reservoir, attach the right adapter, open the bleeder screw, and move fluid until it runs clear and bubble-free. Follow the manual that shipped with your kit, since the exact order can vary by tool type and vehicle design.
- Park on level ground and lift the vehicle, keeping it safely supported on jack stands.
- Top off the master cylinder reservoir with new brake fluid. Never reuse old fluid — kit instructions reject it because old fluid can carry air bubbles and contamination.
- Assemble the hoses and adapters per the manual, then select the adapter that fits the bleeder screw snugly. A loose fit leaks and bleeds poorly.
- Run the clear hose from the bleeder screw into a jar with fresh brake fluid in it, so no air gets sucked back in.
- Bleed the wheel farthest from the