The Brakes...

[xxxj-va]

Cross post from my club board but I'd like some help...

"Help me out folks..
Started up BEFORE Oak Ridge and the mud, etc...My parking brake light
will come on as I use the brakes (not the p-brake). And the pedal,
even at a full stop will gradually sink to the floor at a stoplight
for example. I can pump it and get some pressure back, then if I
push hard I'll hear a "pop" and feel it through the brake pedal and
the p-brake light goes out. Tried to bleed and no matter how many
pumps on the pedal, I can't get more than a trickle from either REAR
bleeder valve although if I disconnect the hard line fluid flows
freely. Checked the front and pumping the pedal with the bleeder
open on either front brake send a gush of fluid. I inspected along
the hard lines for kinks and holes and found nothing. Disconnected
the hard lines in the rear from the junction block and fluid flows
freely there. Is there anything else I can do before I end up paying
someone? I don't think there's a vaccuum leak anywhere. Thanks."

P

 

[Jump This]

Even I am waiting for a reply on this one!!!!!

 

[Eagle]

Do you have ABS?

Did you replace the rear wheel cylinders?

 

[RCP Phx]

I had about the same thing happen after removing the rear axle.Forgot about bleeding the brakes and hit the brake pedal.I had let the whole rear system run dry and that sent the proportioning valve to go into "trouble" mode.A thorough bleeding took care of it!

 

[yellowxj]

 

[yellowxj]

get your self a new master cyl. If I had those problems with my system that is what I would do. Of course my system is older type but the symtoms sound like a master to me. $0.02

 

[Uglygreenxj]

I had the same thing happen to me a while back on my 93'. The pedal was mooshy (that's the technical term he,he!) and no matter how many times I bled the brakes, I couldn't get all the air out or the pedal to firm up.
It turned out to be the master cylinder. It had a very small leak that would allow air to enter the system on the return stroke. Made me crazy till I figured it out.

Dave

 

[Ralph]

Sounds like a bad master cylinder to me too.

RR3

 

[xxxj-va]

Eagle - No ABS. Nothing replaced....RCP - I saw your posts, but my rear drums won't bleed. I'm betting that its air in the system and its settled in the master cylinder where bleeding the brakes won't get it. The light coming on and off is telling me that the combo valve is working and I DO get some rear brakes if I pump the pedal enough and the light goes off.... I am going to pull the master and bench bleed it before I buy a new one or a new combo valve.

Thx

P

 

[RCP Phx]

I pressure bled mine until I got some fluid out at the rear bleeders then just normal bleeding from there!

 

[8Mud]

Sounds like the master to me also. Air in the master (needs to be primed) or a plain bad master. If the master needs to be primed, you got to figure out where the air came from.
I didin´t really understand, what you said about the hard line flowing freely, where it goes into the wheel cylinder?, by the tee on the diff. or up front?
Did you try, pulling the bleeder all together? I´ve had to clean many out with a drill (packed with mud/rust).
Did you pull the dust boots on the rear wheel cylinder, to see if there is any fluid, that bypassed the pistons (and/or sucked air)?
One thing I will say out load, is master cylinder failure, can be a sometimes thing (intermittent) and will come back to bite you. They´ll work a hundred times and then fail, then a hundred more and fail agian. If you even think it´s the master, switch it out.