urq brake system help needed

[Kneale Brownson]

I'm not familiar with URQ brake systems but if you have a "bomb" it 
shouldn't be getting brake fluid from the brake fluid reservoir on the 
brake master cylinder.  It should have a separate hydraulic oil 
reservoir.   If you're talking about the brake fluid reservoir on the brake 
master cylinder becoming discolored and having black bits floating in the 
brake fluid, it sounds as though the seals on the piston inside the MC are 
breaking down.  Usual symptom is the brake pedal bottoming out because the 
fluid bypasses the seals.


At 03:57 PM 01/31/2001 -0600, Steve Marinello wrote:

>Some new twists with the '83 urq...
>
>The brakes started acting like MAYBE the bomb's going
>out...rarely/intermittently hard upon braking, but always coming off some
>mild acceleration.  Pump test checked out...initially.
>
>Noted that the fluid level was down slightly and topped it off.  It went
>down.  Topped it off again...and again, and again ad nauseum until it filled
>up for good (pedal pumping in between fills).  Noted some black particulate
>dregs floating up after about the third fill.  Overfilled slightly the next
>two times and floated the dregs out.  Total volume in was probably 40% of a
>can of Castrol LMA, which is what I had on hand.  Brakes had been flushed
>and filled at the dealer in August 1999.  Car had seen little usage until
>October, at which time it became the everyday car, getting about 70 miles
>per day minimum.  Bomb and regulator replaced in May '94(?) before the first
>q-club Second Creek run in Denver.
>
>Brakes immediately improved in feel (???).  Everything fine with no
>occurences for about three weeks.  But they're back, and more frequent.
>And, the brake fluid in the reservoir has taken on a decidedly darker tint.
>
>Contamination from where?  Where's the breech?  Where to look/check?
>
>With an offering to the Audi Gods, I beseach the lists' assistance.
>
>TIA,
>
>Steve
>
>
>