No Power Brakes 84' 5kt

[David Powell <dpowell@mdtech.is.ge.com>]

Can someone help me diagnose my problem?

The first warning light I got on my dash was because of low rack oil in the
reservoir.  I added rack oil.  The oil was pushed right out of the resrvoir
cap within a very short time.  It never seems to be lower than the <min> mark
when I stop so I've stopped adding oil for the moment.  The steering rack has
been replaced about 70k ago.  There are now obvious leakes other than the 
reservoir cap.  My brakes are fading like crazy sometimes.  Other times they
feel fine.  I never really know what it will be like when I press the pedal.
I've been doing a lot of two footed braking lately.  Once the brakes are 
pumped up they seem to work well.  If I don't use them for a few minutes
they get soft, then very manual.  The brake reservoir is full and never 
needs fluid.  I recently bled the whole system just to see if it would help.
The brakes have not been bled in the last 120k miles as far as I know so I
figured it couldn't hurt.  The power steering is working reasonably.  I've
got a friend that road trips with me who says the settering is getting
worse but I don't notice since I drive the car every day.  It is by no
means manual.  This leads me to believe the power steering pump (remanufactured
ZF) is still working.  The brakes seem very solid and don't go to the floor
when the car is off.  When the car is running I can force the pedal to the
floor with the help of the servor.  I don't know if this is supposed to 
happen.  I reason the brakes would fade with the car off if the master 
cylinder was falty so I don't think it's the master cylinder.
My bentley manuals suggested I remove reservoir return hose from the brake
servo and see if fluid comes out.  None did.  I put everything back together
and pumped up the brakes, then shutdown the car and repeated the test.  Fluid
oozed out slowly.  This may indicate a leakly servo but I don't know if it
is my major problem.  On a car this old there may be several things going
on.  I'm not interested in completely reconditioning the brake system.  I
want to fix the one thing that is causing my power brakes to die completly.
My bently manual suggests I do a few other tests with a pressure guage.  I
don't have one.  I don't want one unless it's cheap.  I'll take it to a 
shop if it comes to that.  What I'm hoping for here is some educated and
experienced guesses about which parts may be failing.  I have a feeling
the shop will test my car and tell me they are all shot, replace the works,
or better yet junk the car.  

Sorry for the verbose / rambling description.  Thanks for any help. 


Some Statistics
1984 5000 Turbo, 191500 miles.
Automatic
Remanufactured steering rack < 120k
Remanufactured Turbo at 190k
Audi Rack Oil in the Rack.
Castrol dot 3/4 in the Brake reservoir



--
David A. Powell				Contract by:	VIRTUALOGIC
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