how do you bench blead the brake master cyl.? my old master cyl. went bad and i had an extra one laying around. i put it in and the pedal still doesnt have much pressure. when the cars off and i press the brakes it gets rock hard. so im thinking since i didnt bench bleed it that i need to. thanks btw its on a 91 civic si

 

take off the lines that go into the master cylinder. then put in a line in place and route it inside the master cylinder then push the pedal in and out. do it a couple of times. after doing that put lines back and bleed the brake lines. hopefully this makes sense

 

hey thanks for the reply, but uh how does one get a line to run into the master cyl? do i have to find some lines from a junkyard and cut em off? or any homedepot comtraptions people have used?

also theres a bolt between the two lines, whats that for? thanks