Need help installing a new master cylinder
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 6,172
Likes: 11
From: somers, ny
Need help installing a new master cylinder
The master cylinder went bad on my 85 (started leaking at the sensor). I bought a rebuild and i'm trying to install it. The instructions for bench bleeding it are pretty sketchy. I put it in a vise (the right way), filled it and pumped the piston per the instructions. The instruction say to do this until there are no air bubbles in the fuild in the reservoir. Well i never had bubbles in the reservoir, and no fuild is being pushed out of either the front or rear fittings. The fluid in the reservoir will slowly leak out of the fittings if i just leave it there for a while (the old does the same thing). I put almost 2 pints thru it and gave up. What am i doing wrong?
Melting Slicks
Joined: Nov 2000
Posts: 3,388
Likes: 1
From: X
Re: Need help installing a new master cylinder (ralph)
I will try to answer your two part question...first of all, if you are not getting any fluid out of the two fittings when you push on the piston the rebuilt is most likely bad. (very common) Second...when you bench bled the break you need to attach the two plastic (usually come with the rebuild) hoses to the fittings then route them into the reservoirs so you can see if any bubbles are in the MC...Like blowing bubbles in your chocolate milk. Here is a pretty good explanation. http://www.vtr.org/maintain/brake-bench-bleeding.html
