When installing or replacing a master cylinder, it is critical that all air is removed from the master cylinder.
1) Place your master cylinder in a vise by the ears (not body). Make sure it is level.
2) Attach a piece of clear plastic hose to the short end of one of the plastic
nozzles. Do the same to the other hose and nozzle.
3) Clip the plastic bridge to the wall and push the ends of the hose through the holes so they are SUBMERGED in the reservoir on either side of the wall.
4) Press the tapered end of the nozzle FIRMLY into the cylinder port hole with a twisting motion. Repeat this procedure on the other port hole.
5) Fill the reservoir with CLEAN brake fluid recommended by the manufacturer.
6) Using full strokes, push the piston in, then release. Do this until ALL the air bubbles have disappeared from the clear plastic hose.
(CAUTION-MASTER CYLINDER WILL NOT BLEED PROPERLY UNLESS HOSES ARE SUBMERGED IN BRAKE FLUID UNTIL THE BLEEDING PROCESS IS COMPLETED.)
Now mount master cylinder and avoid brake fluid leaking out of front and rear ports during installation.
Always bench bleed master cylinder first, then the system. There are four methods: gravity, pressure, vacuum, and pedal bleeding. The most common is pedal. This process is as follows:
1) Pedal bleeding is a 2 person job - one person pumps the pedal, and the other operates the valves. Open each bleeder valve individually, then depress the pedal one full stroke. The person watching the valves looks for air bubbles and closes the bleeder valve before the pedal is slowly returned to the released position. (NOTE: To assure that no air is siphoned into the system, a plastic hose should be connected to the valve. The other end of the hose should be submerged in container of brake fluid. Also, the valve must be closed at the end of each stroke before releasing the pedal.)
2) Continue in this manner until all calipers are bled.
3) After each caliper is bled, refill the master cylinder and frequently check the reservoir.
4) Bleed the longest line first, following this order: right-rear-outer, right-rear-inner, left-rear-outer, left-rear-inner, right-front and left-front.