Where's my brake fluid going?(`88 90q)

[barry myers <myers@ll.mit.edu>]

Greetings,
    Could someone please help me with a brake problem .

The car is a `88 90q. I'm needing to top off the brake fluid reservoir
about every other day.
It leaks to the point that the dash light comes on. No problems with the
clutch master or
slave. The brake calipers are all ok .

There seems to be a large leak coming from  the bottom of the brake
booster. As far as I can tell the leak
is not coming from the reservoir sealing plugs that connect the
reservoir to the master cylinder.

The brake booster passes the Bentley test of pumping and starting the
engine and looking for the pedal
drop. The pedal does not fade away after pressing hard for an extended
period. (I'm thinking
if the brake master cly. was on it's way out the pedal would collapse
after awhile.)

Is there anyway that the brake fluid can enter the booster causing a
leak? I've noticed that the Bentley
suggests that the "O" ring must be changed when the master is replaced.
Has anyone seen this
"O" ring fail.

Any help would be appreciated.

Thanks,
Barry M