ur-quattro hydraulic question

["Pennell, Andrew" <APennel@bsadpo.emba.uvm.edu>]

	Hello, I am hoping to find a possible answer to a problem in my 82
urq's hydraulic system. For some time I have notice that when I go
around long curves and put consistent pressure on the steering wheel I
feel a "twitch" or a "thump" come back through the wheel. The length of
time between the twitches seem to be on a consistent interval.
Eventually I noticed that at idle the hydraulic pump made a peculiar
noise at the same time interval as the twitch. The only way I can
describe this noise is that it is similar to when on a large truck the
pressure relief valve goes off and you hear a short "psssssst". I feel
that a pressure relief valve located somewhere in the hydraulic system
is creating a pulse that disturbs the consistent power in the power
steering thus creating a twitch in the wheel.....but this is not the end
of the story.
	The symptoms that I just described are not really bothering me. It only
shows up at speed and when pressure is applied to the wheel with
somewhat heavy force. What is bothering me is a problem with my brakes.
If I hit my brake pedal hard the brake warning light comes on and the
pedal is very hard for a moment than you can feel the power brakes kick
in. In addition, on a cold day it takes 20-30 seconds for the brake
system to build pressure and the hard pedal symptom is more pronounced. 
	Now, I believe these symptoms are related. What I don't know is if the
problem is related to the hydraulic pump or the pressure accumulator or
both. What are the signs that these units are going? Is the "pulsing"
that the pump is making representative of a pump on it last leg? Do
accumulators go bad frequently?
	Any feedback related to this issue or similar experiences would be much
appreciated. - thank you 


*****************************************
Andrew Pennell
82' ur-q
92 SAAB 900T