Ford F7AZ-2140-AA Master Cylinder Assembly

In order to overhaul the brake master cylinder, consider whether you can get a new one at a reasonable price. Put some rags underneath the brake line fittings and cover up the line ends when you disconnect them. Use a flare-nut wrench to unscrew the tube nuts, plug up their ends and also disconnect the brake warning light connector. Take off the mounting nuts and separate the brake master cylinder from it. Remove the reservoir cap and use a brake system cleaner to clean both it and the cylinder. Replace if necessary by examining for damage in bore. Then grease new reservoir grommets and push them into cylinder body. Grease bore and piston assemblies, and press body onto the reservoir. Insert piston assemblies, then snap ring should be installed before capping is attached on top of the diaphragm that may need changing if damaged. To do bench bleed, fill both reservoirs with fluid as well as place plugs to expel air from those fittings.