Q: How Should I Remove and Install a Master Cylinder?
A: Brake fluid can damage paint or finished surfaces, so it is important to cover all body parts and be cautious not to spill any fluid during the removal process. Any spilled brake fluid should be cleaned up immediately and the area should be washed with large amounts of water. It is also important to note that different vehicle models may have different factory systems installed for the Anti-lock brake system (ABS), so it is necessary to determine which system is on your vehicle for part identification and torque specifications. To begin the removal process, disconnect the cable(s) from the negative battery terminal(s) and depress the brake pedal several times to remove all vacuum from the power Brake Booster. Remove the brake master cylinder access cover in the cowl and clean the brake master cylinder and reservoir thoroughly with brake cleaner. Remove as much fluid as possible from the reservoir with a syringe and unplug the electrical connector for the brake fluid level warning switch. Place rags under the fittings and prepare caps or plastic bags to cover the ends of the lines once they're disconnected. Loosen the fittings at the ends of the Brake Lines where they enter the brake master cylinder using a flare-nut wrench and carefully move the brake lines away from the brake master cylinder, plugging the ends to prevent contamination. Remove the brake master cylinder mounting nuts and pull the brake master cylinder off the studs to remove it, being careful not to spill fluid or bend the brake lines. To install the new brake master cylinder, bench bleed it before installing by mounting it in a vise and attaching a pair of brake master cylinder bleeder tubes to the outlet ports. Fill the reservoir with brake fluid and slowly push the pistons into the brake master cylinder using a large Phillips screwdriver to expel air from the pressure chambers. Repeat this procedure until no more air bubbles are present and remove the bleed tubes, installing plugs in the open ports to prevent fluid leakage and air from entering. Install a new vacuum seal on the brake master cylinder and then install the reservoir cover. Install the brake master cylinder over the studs on the power brake booster and tighten the attaching nuts finger tight. Thread the brake line fittings into the brake master cylinder, being careful not to strip the threads, and tighten the mounting nuts and brake line fittings securely. Fill the brake master cylinder reservoir with the correct fluid and bleed the brake system as described. Finally, test the operation of the brake system carefully before placing the vehicle into normal service.