5ktq after-run, hydraulic pump[wasnew to Audi, new to the list]

[Ben Swann]

[<snip>
QA. 1) the after-run coolant pump has been "deleted" - I'm guessing because it 
may have developed a coolant leak.  I understand that this pump circulates 
coolant after shutdown in conjunction with the cooling fan to cool the 
waterjacket and the (water-cooled) turbo.  How frequently does the 
afterun cooling system operate - is it only after "spirited" driving with 
hot ambient temperatures, or is it pretty much any time the engine has 
been heated to operating temperature and the ambient temperatures are 70F 
or greater?  Is there a good (read: inexpensive) source for these pumps?  
I do not have the old one, so rebuilding is not an option.  My immediate 
area is (painfully) devoid of any Audi parts cars of this vintage, however 
I may be able to find something a little further afield.


The after-run pump runs after an extensive heat soak.  I usually does not kick in on short trips, and if engine has had a chance to cool down  - low load medium speed it won't  likely run.  It is good to let the engine cool down by idleing for a minute if you think it is on the warm side.

So don't panic to replace, but source one and replace it before the weather get warm and/or you do some "heated" driving.  Chris at force5auto.com has had them amonhg others.

Q2) the hydraulic pump is leaking - in persuing the archives I've learned
that this is not uncommon.  There is a rebuild kit (or a few o-rings and a
seal, anyways) available from the dealer for around $50 CDN.  Has anyone
successfully rebuilt their hydraulic pump?  I understand the procedure is
detailed in the Bentley (which I hope to have by the first of the week)  
but I would appreciate any advice based on personal experience that can be
offered, as the alternative is a $250 CDN rebuilt unit.

A. Not me.  Rod @thepartsconection.com has a decent economical rebuild.  I'd certainly be interested in hearing your results if you decide to undertake it.

Thanks in advance for any advice/input offered.

Drew]