Bench Bleed New Master Cylinder???

Frame up rebuild with all new brake system. Drums, shoes, wheel cylinders, lines, and master cylinder.
Moved on to installing new body. I plan on bleeding the brakes later on. Then I saw a link here where the question was asked if someone bench bled the master cylinder before installing. Say What???

I did not bench bleed the master cylinder. I do not know what bench bleeding is. Do I need remove master cylinder and do this or can I just bleed out the lines like normal????

Mike

 

Bench bleeding is is basically putting temporary line(s) from the master back to the reservoir, fill the reservoir with clean fluid, , make sure the line(s) are submerged in the fluid begin pushing the piston in the master to bleed air from the master before bleeding the rest of the system. If you dont bleed it air bubbles will be in the system and you will have a low pedal. It can be done in the car if you disconnect the the brake line and put lines back to the reservoir.

 

Thanks guys. When I bleed wheel cylinders, I put a line on the nipple that goes into container with fresh brake fluid--Same idea I think. When finished bench bleeding master and the temporary lines are disconnected--- do I need to take precautions so air does not enter or brake fluid leaking out while reinstalling into jeep? Of course the cap to master cylinder is on tight.
Mike

 

It may drip a little but air isnt a concern since you will bleed the system after its reassembled

 

You are only insuring there is no air in the pistons of the master cylinder, no problem disconnection, try not to get brake fluid on paint, not a problem with synthetic. Bench bleeding can also be done in a vehicle, more difficult in the confines of jeep, but if you have good access it's possible. Also if your kit came with plugs you can insert them to keep any dribble contained.