Underhood hydraulic pump

[scot@phoenix.phoenix.net (Scot VanAlstine)]

I have a 1986 4000cs Quattro.  There is a hydraulic pump under the hood
that has one hose going to a reservoir on the fire wall. One of the hoses
for this pump is leaking slightly.  It's been chafed by the mount that
holds it stationary.  What does it provide the hydraulics to?  Is this what
uses the Pentosin that I hear you guys talking about in barely a whisper?
I know, I know "Its covered in the Bentley manual". Well it's ordered but
its taking forever to get here.

Enjoying my first Audi.

Scot VanAlstine