To remove the Brake Master Cylinder, place rags under the brake line fittings and prepare caps or plastic bags to cover the ends of the lines after disconnection, taking care to avoid spilling brake fluid, which can damage paint. Unscrew the tube nuts at the ends of the brake lines using a flare-nut wrench to prevent rounding off the flats. Pull the brake lines slightly away from the Brake Master Cylinder and plug the ends to prevent contamination. Disconnect the brake warning light electrical connector if equipped, remove the two mounting nuts, and detach the Brake Master Cylinder from the vehicle. Remove the reservoir cap and discard any remaining fluid. For overhaul, mount the Brake Master Cylinder in a vise, remove the primary piston snap-ring, and extract the primary piston assembly. Remove the secondary piston assembly, possibly inverting the Brake Master Cylinder and tapping it against a block of wood. If fluid has leaked past the reservoir grommets, pry the reservoir from the cylinder body, remove the grommets, and clean the components with brake system cleaner. Inspect the cylinder bore for corrosion or damage, replacing the Brake Master Cylinder if necessary. Lubricate new reservoir grommets with silicone grease or clean brake fluid, press them into the Brake Master Cylinder body, and then press the Brake Master Cylinder body onto the reservoir. Lubricate the cylinder bore and piston assemblies with clean brake fluid, insert the secondary piston assembly, and install the primary piston assembly with the snap-ring. Inspect the reservoir cap and diaphragm for damage, replacing any faulty parts. When the Brake Master Cylinder is removed, the hydraulic system must be bled, which can be expedited by filling and bench bleeding the Brake Master Cylinder before installation. Insert threaded plugs into the cylinder outlet holes, fill the reservoirs with brake fluid, and loosen one plug at a time to expel air from the Brake Master Cylinder. Stroke the piston several times for each outlet to ensure all air is expelled, using an alternative method to keep air from being drawn back in. Refill the Brake Master Cylinder reservoirs and install the diaphragm and cap assembly. For installation on 2002 and earlier models, apply a vacuum to the power booster and adjust the pushrod length as needed before carefully installing the Brake Master Cylinder and bleeding the brakes.
