'84 Audi 4000s Quattro brake issues, balancing

Hi, I've had problems with this for a while, in the mean time I've been driving my other car, but a couple years ago I replaced the disc pads on all 4 wheels of my vehicle. I noticed the front brakes dragging
horribly and the rears seemingly getting no fluid. After some investigation (on and off while I was at college and driving something else), I found the brake balancer and put fluid to the rear, to discover and broken line in the rear. I replaced this and then set about bleeding the system. I couldn't bleed more than a half pedal's worth to either rear tire without the balancer tripping. I know I have no more leaks, and it's getting harder and harder to have the balancer recenter itself. It will not do it itself on starting like most cars, even if pressure is restored, bleeding that valve on the proportioning valve is the only thing I can do to get pressure to the rear and I have to bleed 3-4 pedals worth. My current situation is all wheels seem to be dragging now, the rears quite bad, to the point of them really needing a rest after a mile drive. The rears still aren't connected to the brake pedal though, upon hitting the brakes I can tell only the fronts are stopping, I've verified this by jacking up the rears and checking with someone hitting the brakes.
I've also read something once of a person (diff car) having their pedal constantly depress slightly on the brake servo, causing the car to always have the brake slightly applied. He could not figure how to correct it and put washers under the servo to raise it out a bit and 'recenter' it that way. Could this be related at all?
I really would like to fix this so I can drive it some, Thanks a lot, Chris
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Park brake cable has enough slack ? That's what did it with my '87 Quattro
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The rear brakes typically do not provide any stopping effort until you use the brake pedal quite hard. The centering that you have been doing might have thrown out this relationship.
Also, the brakes need to be bled with a pressure system and not by pumping like in most other cars. This is due, in part, to the rear parking brakes which have a threaded adjusting stud inside the rear caliper piston. When rebuilding the rears one needs to both, push and turn to get the piston in.
I would try to return the 'centering' to where you found it, pressure bleed the system and then investigate what I think is your real problem - a bad master cylinder.
The Master Cylinder typically fails by causing the brakes to drag and lock up. This is due to overheating because the MC is located directly behind the radiator fan and gets hot a lot.
The DIY test for this is to bring a bucket of ice water with you and drive until the brakes grab or seize. Then get out and pour the ice water all over the master cylinder. If this frees things up you need to replace the master cylinder.
There is a current thread at the audiworld forum that shows a cheap and easy pressure bleeder.
http://forums.audiworld.com/v8 /
This is the type 44 forum.
Tony '91 100q 5spd
ItJstAGame wrote:

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