What is the proper way to bench bleed a master cylinder for a 1995 grand prix?
Before installing the master cylinder you do need to bench bleed it. Some brake master cylinders come with a bleeding kit to make bench bleeding the master cylinder easier, purchase a bench bleeding kit if yours did not come with one. The master cylinder bench bleeding kit consists of adapter fittings that screw into the master cylinder and tubes that attach to the fittings of the master cylinder. Place the master cylinder in a vise and attach the brake master cylinder bleeding kit routing the tubes into the master cylinder reservoir. While keeping the tubes submerged in brake fluid of ther reservoir, push the master cylinder piston in repeatedly using a screwdriver. You will see air traveling through the tubes into the reservoir by keeping the tubes in the fluid you are preventing air from re-entering the master cylinder when the piston returns. When there is no more air traveling through the tubes the master cylinder is ready to be installed. DenLorsTools.com has a related tech article that goes into more detail, the link is in the left column. See the Related Links for "DenLors - Master Cylinder Bench Bleeding" to the bottom for the answer.