You can also bleed the brakes with a vacuum pump or syringe. Then repeat over and over until there are no bubbles. With a bleed bottle, the bleed screw nipple is attached to a hose submerged in brake fluid, and you pump the pedal yourself with the screw open the fluid keeps air from being sucked back into the caliper. With an assistant, you have them pump the brakes and hold the pedal, then you loosen the bleed screw to let out the air bubbles and fluid.

You will need an assistant to pump the brakes on command, or you can employ one of the many one-person brake bleeding techniques, like the Wilwood Brake Bleeding Bottle. The most critical aspect of bleeding brakes is not to let any air back into the system. Many racers flush out the old fluid after every race weekend, if not every race! Most people neglect this maintenance on daily drivers, but even on commuter cars it is essential to flush it every other year and every year on any car driven hard. This is the same process you would use to flush the system of old fluid and fill with higher performance Wilwood High Temp 570 or EXP 600 PLUS brake fluid. Careful not to drip any brake fluid on painted surfaces.Īfter connecting the brake lines to the master cylinder, proportioning valve, and all four calipers, it is time to bleed the whole system to fill the calipers with fluid and purge any air in the lines. Now you are all set to reinstall the master cylinder in the car and connect it to the brake lines.

Continue alternating until you no longer see bubbles in the hoses.

Pump the piston with a dowel, screwdriver, or the attached pushrod slowly through its entire stroke several times, then several short, fast strokes.

Thread plastic fittings into the output ports, and route the hoses back to the reservoir.

Try to get it level, or even with the front pointed down slightly, so air bubbles can escape through the compensating port or brake outputs.

Clamp the master cylinder in a way that won't damage it, typically by the mounting flange.

The only escape the bubbles have is back into the fluid reservoir through a tiny hole at the back of the bore, and most cars mount the master cylinder flat or at a slight upward angle, trapping air at the far end of the bore.īench bleeding is easy, but you will need a bench-mounted vice to hold the master cylinder. You will never have an appropriately firm pedal as long as there are still air bubbles that need to be compressed in front of the piston, and there is little chance they will find their way out on their own. It is crucial you bench bleed the master cylinder because, as mounted to the car, it is impossible to get all the air out of the piston bore.

If you are installing a new master cylinder, Wilwood or OEM style, it is already out! But test fit it to the firewall/booster first and make sure everything is right, including the pushrod length, before putting fluid in it. Available in Black Ops and Gold Ops finishes.The easiest part of bleeding the brake system is bench bleeding the master cylinder, though it requires taking it out of the car. Brake light and starter interrupt safety switch housing assemblies as well as CAN Bus brake and starter interrupt safety switch linkage kits provide compatibility with older stock wiring and newer CAN Bus systems (sold separately). Choose between mirror mount or clean mount options. With fully adjustable lever, machined fluid reservoirs and clearance for stock switch housings, this versatile system will drastically improve both the look and feel of your controls. Race driven PM Radial Brake Master Cylinders feature built-in reservoirs which deliver stunning performance and style for any bike.

Driven racing master cylinder