Brakes Puke

[Murfdawg]

I have a 75 gmc c25 with a brake problem. It started with too much bias in the rear brakes but now brake fluid sprays out the top of the master cylinder when the brakes are applied. It has a very firm pedal. The brakes were rebuilt less than 1000 miles ago. Any help will be greatly appreciated. Thanks!

[Shugalou]

Booster sounds like it's shot if the pedal is hard. Master sounds like it might not be functioning either if it's not pushing the fluid through the lines.

If the master leaked into the booster that is why the booster may have stopped working.

What shape are the flex lines? They can collapse internally and look fine outside. Put stainless in if you are gonna replace.

No brake light warning on the dash? So sounds like your prop valve is working properly.

[Murfdawg]

Thanks Shugalou! You have confirmed my suspicions.

[Shugalou]

No prob Murf - I learned a lot from the members here so I like to give back in areas I have experience.

When I brought my truck home I wanted to clean the booster because it was all rusted. When I put it back on it stopped working and I had the hard pedal...The lines were froze to the master so in the end I rebuilt the entire system with all new parts - Lines, calipers and all. Along the way I ran into many problems and these guys on the forum got me through it...I recommend reading some of posts on my brake problems if you plan on tackling the job yourself.