Master Cylinder Bench Bleeding for Chevrolet Chevy P12 Chassis 1999

Bench bleeding removes the air from the master cylinder prior to the installation. Bench bleeding reduces the amount of bleeding needed after the installation onto the vehicle.

1. Plug the outlet ports.
2. Mount the master cylinder in a vise with the front end tightly tilted slightly down.
3. Fill the reservoir with clean brake fluid.
4. Stroke the primary piston about 25 mm (1 in) several times using a smooth, rounded end tool. Resistance to the primary piston travel will not allow the full 25 mm (1 in) stroke when air is bled from the master cylinder.
5. Reposition the master cylinder in the vise with the front end tilted slightly up.
6. Repeat the stroke to the primary piston of about 25 mm (1 in) several times.
7. Reposition the master cylinder in a vise to the level position.
8. Loosen the plug(s) one at a time.
9. Push the piston into the bore in order to force the air from the cylinder.
10. Tighten the plug(s) before the piston returns to the original position in order to prevent air from being sucked into the cylinder.
11. Fill the reservoir. Refer to Master Cylinder Reservoir Filling .
12. Perform the normal bleeding procedure after the master cylinder is installed. Refer to Hydraulic Brake System Bleeding .