Pressure Acummulator Discoveries

[Bob Kunz <bkunz@hpbs114.boi.hp.com>]

Hi folks,

Finally replaced the pressure acummulator this weekend. You may (or may not)
recall that I had no reserve after engine shut down, but that power steering
and brakes were fine while running. I discovered some interesting details
along the way.

The replacement part was bought from PAP, perfect fit. Oil came from a local
parts outfit (Bow-Wow for those on the west coast). There are two types.
One is synthetic and has a temp range to 130 C, the other has no synthetic
compenents and goes to 100 C. Pentosin (sp?) in the green can is "11s"
in the white can is "7.1s". The mostly knowledgeable person at Bow-Wow 
said that pre 1984 used 7.1s and 1984 and newer used 11s. 11s is the
synthetic. $16.95 a liter.

I had mistakenly used hydraulic jack oil (comments about being an idiot
from the group inserted here) in the system to top it off during the car's
life. Had to flush out all the old stuff and replace with new. Upon
reviewing Bently, I found at least 8 references to Audi's part number for
this fluid but aparently ignored them all before.

The result of all this is the hard to believe part. The car now runs better.
It appears that the hydraulic pump was sucking mucho power out of the engine
which exhibited itself as higher than normal operating temperatures, less
power off the line and almost stalling when the clutch is depressed. All
of this has gone away with the new acummulator and fluid. Can't figure
out what was the real cause. I would lean towards the accumulator because
that means the pump would have to move more fluid to keep up, but who
knows?

The lesson here is those of you who have put off changing out the acummulator
should do it pronto. How you know was discussed recently. And those of you
with idle problems should also look for abnormal engine drag conditions like
the hydraulic pump.

Bob Kunz
bkunz@boi.hp.com
'86 5000S Wagon