GM 19209275
Master Cylinder

Secure the Brake Master Cylinder mounting flange on a workbench vise so you can access the back of the main Piston. Put suitable fittings on top of master cylinder ports so they match the brake line flare seat and can connect to hoses. Attach transparent hoses to the master cylinder ports through their fittings before placing them inside the reservoir. Put complete delco supreme 11 (R) gm brake fluid p/n 12377967 or its canadian equivalent dot-3 into the reservoir until the fluid lines reach their destination. Use sealed clean fluids from the original container. Push and let go the main Piston with a round tool for up to 25mm depths several times to check fluid flow through the ports. Pressing the primary cylinder requires more force and reduces its movement due to the air evacuation from the primary and secondary pistons. Regularly depress the primary Piston until the ports let out fluid without showing air bubbles. Replace the clear hoses inside the reservoir and put back the master cylinder parts. Next disconnect the hose fittings from their ports and use a cloth to cover the master cylinder before taking it off.

First use the required tool to drain brake fluid from the master cylinder tank. Separate the electrical connector for the fluid sensor while using rubber caps to seal each end of the brake lines as you disconnect them from the abs module to the master cylinder. Take out the Brake Master Cylinder after unthreading its mounting bolts. Prepare the master cylinder through bench bleeding then install it onto the mounting studs. Bolt the mounting nuts into proper position and make sure they reach 30 n.m torque settings during tightening. Plug in the fluid sensor electrical connection followed by sealing the Brake Line tubing ends after installing them between the abs module and master cylinder unit. Tighten all fittings to 17 n.m (13 lb ft). Fill the reservoir with brake fluid while performing system checks and let air out through the brake lines.

Use the required tool to take brake fluid from the master cylinder reservoir before replacing the Brake Master Cylinder. To protect the brake system from external risks disconnect the electrical sensor and take out the brake pipes from the abs module to the master cylinder. Drainage caps should be fitted on all exposed brake pipe ends during this process. Take off all mounting bolts and take the master cylinder out. Mount the master cylinder after bleeding it in a bench setting on the mounting studs. Replace the mounting bolts by hand-tightening and completing them to 30 n.m (22 lb ft) with torque. Reattach the fluid sensor electrical connector first then put back the brake lines to the master cylinder and tighten their fittings to 17 n.m (13 lb ft) while also removing the rubber caps or plugs. Check the brake system function while filling the reservoir and perform required brake bleeding procedures.

Reconnect the fluid lever sensor electrical connector, remove the rubber caps or plugs from the brake lines, and install the brake lines from the ABS module to the master cylinder, tightening the fittings to 19 Nm (14 ft. lbs.).