The Brake Master Cylinder is located in the engine compartment, mounted to the power
Brake Booster. Begin by disconnecting the cable from the negative terminal of the battery. Remove as much fluid as possible from the reservoir using a syringe or an old turkey baster. For later models with manual trans axles, disconnect the clutch fluid hose from the Brake Master Cylinder reservoir and plug the line or wrap it with a plastic bag. Place rags under the fluid fittings and prepare caps or plastic bags to cover the ends of the lines once disconnected. Loosen the fittings at the ends of the
Brake Lines where they enter the Brake Master Cylinder, using a flare-nut wrench to prevent rounding off the corners. Pull the brake lines slightly away from the Brake Master Cylinder and plug the ends to prevent contamination. Disconnect the electrical connector at the brake fluid level switch on the Brake Master Cylinder reservoir, ensuring to pull back the locking tab before removal, then remove the nuts attaching the Brake Master Cylinder to the power booster and pull the Brake Master Cylinder off the studs. If installing a new Brake Master Cylinder, drive out the two retaining pins that hold the reservoir to the Brake Master Cylinder body and transfer the reservoir to the new Brake Master Cylinder, ensuring to install new seats. Bench bleed the new Brake Master Cylinder before installation by mounting it in a vise and attaching a pair of bleeder tubes to the outlet ports. Fill the reservoir with the recommended brake fluid and slowly push the pistons into the Brake Master Cylinder to expel air into the reservoir, repeating until no more air bubbles are present. Remove the bleed tubes one at a time, install plugs in the open ports, and then install the reservoir cap. Install the Brake Master Cylinder over the studs on the power brake booster and tighten the attaching nuts only finger tight initially, ensuring to install a new O-ring onto the sleeve of the Brake Master Cylinder. Thread the brake line fittings into the Brake Master Cylinder by hand, ensuring they are started straight, and then tighten the mounting nuts to the specified torque before securing the brake line fittings. Connect the brake fluid switch electrical connector and, for models with manual trans axles, connect the fluid hose from the clutch Brake Master Cylinder. Fill the Brake Master Cylinder reservoir with fluid and bleed the cylinder on the vehicle by having an assistant depress the brake pedal and hold it to the floor while loosening the fitting to allow air and fluid to escape, repeating this until the fluid is clear of air bubbles. Finally, test the operation of the brake system carefully before placing the vehicle into normal service.