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Question about '86 535i Brakes



Car (before I got it):
1986 535i w/abs/hydraulic power assist brakes, well maintained (regular
bleeding) but not driven enough or much at all in the last year or two.
Rotors rusted, brake fluid fairly clean, car pushes easily--nothing seized.

Initial symptoms:
Brakes seizing but pulsing like the pedal was being taped
After a mile or two right front wheel gets hot.
Pulled tire, opened bleeder, fluid comes out, closed bleeder, depressed
pedal, fluid comes out then stops,
No amount of pedal pumping would produce any fluid at the caliper.
Parked car, ordered rotors, caliper kits, pads. SS lines, super blue, etc.

Worked performed:
Replaced pads, rotors, rebuilt calipers, installed SS brake lines.
Calipers had goop in them put looked good, no rust, seals ok, replaced seals
anyway.
Kept old hoses clamped and was careful not to let fluid out of lines while
replacing.
Lost about a teaspoon per wheel. Fluid in reservoir never noticeable went
down.
Went to bleed first caliper, spongy brake pedal and no fluid making it to
the caliper.
Tried all 4 corners, got the same results.
The pedal feel changes as I depress it.  The first ten pumps will be real
spongy, then it will get firm for 10-20 pumps and when its firm the brake
light lights up from about 1/4 to 3/4 of the pedal travel, (the light is off
at the beginning and the end of the pump) This cycle repeats fairly
regularly.
If I disconnect the lower of the two sensors on the Hydraulic reservoir the
brake light stays off.
The power steering works well (not as easy as an American car but comparable
to other BMWs I've driven)
The power steering fluid is clean and at the right level, I see no obvious
leaks, disconnected sensors, etc. around the hydraulic reservoir or the
power assist module.
Through all this pumping I never got a single drop of fluid out of the
bleeders.

I have read the factory manual I got with the car but the trouble shooting
sections does not give enough detail.
I have ordered a Bentley's manual overnight but am anxious to hear what the
list has to say.
The factory manual details the ABS bleeding procedure exactly as a non-abs
car.  I was still very careful to let as little fluid out of the system as
possible.  Is there something I have to disable on the ABS to bleed this
thing?
Thanks in advance.
Doss

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