Posted by Paul(in NY) on Saturday, August 07, 2004 at 7:16PM :
In Reply to: What does it mean to "bench bleed" the Master Cyl? posted by J-Gilly on Saturday, August 07, 2004 at 6:32PM :
I always bench bleed my MC's before putting on the vehicle. It makes quick work of getting them primed, rid of air, ready to hook up and bleed the system.
I have two fittings with short plastic hoses.
I fill the MC chambers, run the hoses from the brake fluid out ports and the other end of the hose back into the rpoper chamber for that port. Then fill the MC chambers with brake fluid. Slowly, with full strokes push in on the MC piston with a rod and keep doing this until you are circulating brake fluid out of the port and back into the chamber (with NO air bubbles). Keep your eye on the level of the brake fluid. If it goes down, add more, so you dont pump air. When all air is gone, and they are pushing brake fluid, I put plastic caps in the brake fluid out ports, install and hook up the brake lines immediatelly.
Then go through the entire brake bleeding sequence until you are positive no air is in the system.
With shoe type brakes, be sure the MC you purchased has the redisual check valves.
Disk type brakes do not require redisual check valves unless the MC is at the same level or lower than the brake calipers, then a special disk brake redisual check valve is available.
Paul