How to replace a master cylinder

To remove the brake master cylinder, start by removing the cover from the air filter housing and disconnect the electrical connector for the brake fluid level warning switch. Use a syringe to remove as much fluid as possible from the reservoir. If there is a manual transaxle, clamp off the fluid feed hose to the clutch master cylinder and detach the hose from the brake fluid reservoir. Prepare rags, caps, or plastic bags to cover the ends of the lines once they're disconnected. Use a flare-nut wrench to loosen the fittings at the ends of the Brake Lines where they enter the brake master cylinder. Pull the brake lines away from the brake master cylinder and plug the ends to prevent contamination. Remove the nuts attaching the brake master cylinder to the power booster, taking care not to spill any fluid. For installation, bench bleed the new brake master cylinder before installing it. Mount the brake master cylinder in a vise, clamping the jaws on the mounting flange. Attach a pair of brake master cylinder bleeder tubes to the outlet ports and fill the reservoir with recommended brake fluid. Slowly push the pistons into the brake master cylinder to expel air into the reservoir. Repeat until no more air bubbles are present. Remove the bleed tubes and install plugs in the open ports. Adjust the booster pushrod length if necessary and install a new O-ring on the brake master cylinder body. Install the reservoir cover, then position the brake master cylinder over the studs on the power Brake Booster and finger-tighten the attaching nuts. Thread the brake line fittings into the brake master cylinder, ensuring not to strip the threads. Fully tighten the mounting nuts, then the brake line fittings. Fill the reservoir with fluid and proceed to bleed the brake master cylinder and the brake system. Test the operation of the brake system carefully before putting the vehicle into normal service.