[s-cars] Is it time to replace my hydraulic brake booster?

[Thomas Rodriguez]

Folks,

As mentioned in some of my other posts, I have done a bunch of work on
my brake system but I am still not happy with the pedal feel which
still has lots of free play and engages close to the floor with little
to no boost feel.  Work to date includes brake fluid replace & bleed,
inspect pads & rotors (good shape), replace leaking J-hose, replace
faulty pressure accumulator (bomb); replace and bleed Pentosin
hydraulic fluid including cleaning the hydraulic reservoir and screen
and installing a 3/8-inch magnefine filter on the return line to the
reservoir.

On Saturday I ran the diagnostic test for a leaking hydraulic brake
booster as described in the Bentley manual and in a helpful post on
Quattroworld. The test method was to run engine for a few seconds at
2,000 rpm, turn engine off, disconnect hydraulic fluid return line
from booster, observe for a couple of minutes: good booster will
release only a drop or two of fluid, leaking booster will release a
steady flow of fluid.  During the test my booster released a slow but
steady flow of about 1 to 2 milliliters per minute which I caught with
a rag.

Does this rate of flow fail the test or is this within a "normal"
range?  Should I replace my booster?

Assuming all other components of the braking system are in good order,
what would be the symptoms of a leaking hydraulic brake booster? (i.e.
how would a leaking booster affect the feel of the brake pedal in
terms free play, engagement point, boost feel, etc?)

Thanks,
Tom
'95 S6