: Them are the brakes...,



creeker
10-01-10, 06:51 PM
well most of the time, just before I bought my 80 cdv. (6 weeks ago) the rear brakes were redone, new shoes and drums turned, took car in to have rear brakes adusted as pedal would go tho the floor, not as unsafe as it sounds, with only
a slight push on pedal the brakes are up again, it doesn't feel like air as it is not spongy,my mechanic said it sounds like master cylinder, is it a big job to install new master cylinder?, what goes wrong with master cylinder to cause this? is there
a way to test and verify it is the master cylinder?, Thanks.

outsider
10-01-10, 07:23 PM
It sounds like the master cylinder. what happens is the plunger can wear out and not make a good enough seal/not make enough "combustion" for lack of better word...

This happened just recently on my girlfriend's father's truck. We first tried to replace the power brake booster, that didn't help...the new master cylinder, however, fixed the problem.

It's easy to do, remove the old one (drain the fluid that's in the reservoir first) and put the new one on just like the old one was, then fill, bleed the brakes all the way around and top off with fluid.

creeker
10-01-10, 07:38 PM
It sounds like the master cylinder. what happens is the plunger can wear out and not make a good enough seal/not make enough "combustion" for lack of better word...

This happened just recently on my girlfriend's father's truck. We first tried to replace the power brake booster, that didn't help...the new master cylinder, however, fixed the problem.

It's easy to do, remove the old one (drain the fluid that's in the reservoir first) and put the new one on just like the old one was, then fill, bleed the brakes all the way around and top off with fluid.

Thanks a lot for your help, just curious about bleeding the brakes, if no fluid
drains out of lines beyond the master cylinder, (to wheels) why is it necessary
to bleed the lines?.

albymangled
10-01-10, 07:46 PM
Why is it necessary to bleed the lines?

So that the pedal isn't spongy / travels to the floor on application is the short answer.

So that any air allowed to enter the system during the disconnection and reconnection of the lines is the real answer.

You'll have to do it....it isn't hard if you have a little help....

creeker
10-01-10, 08:01 PM
Why is it necessary to bleed the lines?

So that the pedal isn't spongy / travels to the floor on application is the short answer.

So that any air allowed to enter the system during the disconnection and reconnection of the lines is the real answer.

You'll have to do it....it isn't hard if you have a little help....

Thanks, a case of beer should cover the extra help.

jayoldschool
10-01-10, 08:07 PM
Bench bleed the master cylinder before install, then bleed all brakes in the proper order after install.

creeker
10-01-10, 08:18 PM
Bench bleed the master cylinder before install, then bleed all brakes in the proper order after install.

Thanks, what's the proper order?.

jayoldschool
10-01-10, 09:15 PM
Fl, fr, rl, rr

The-Dullahan
10-03-10, 12:32 AM
Had to deal with this in my car. A real mess. Everything was rusty and ready to snap off, but the master Cylinder miraculously survived. The paring brake is entirely useless, so I'm not street legal, but aside from that the brakes are wondrous.

It shouldn't be remarkably expensive OR time consuming.

The-Dullahan
10-03-10, 12:33 AM
a case of beer should cover the extra help.

How soon should I be there?