Fix or replace oil pan on A6 Avant Quattro

[Kevin Smith]

I would never weld an oil pan or any other engine component ON the car
(except maybe a bracket), so I had planned to remove it and clean it using
an acid bath and toluene. It's not very hard to get parts clean when using
the right chemicals, and a good stiff bristle brush. I was going to scrape
and scrub any heavy residue off, and then soak it in the acid bath, and then
scrub it again with a pad, and then hand wash it with rags and toluene to
get any residual material off, and then use a new wire brush to clean the
surface to be welded. I've done enough cleaning and welding of parts over
the years to feel very confident in my ability to do that. I have the
materials and equipment for cleaning at my disposal, but welding aluminum is
not something I have done enough of yet.

Because of it being at the drain hole I figured I may as well just replace
the pan instead. That way it eliminates having to weld up onto the drain
neck area and end up having to re-tap the threads for a proper seal with the
plug. I'm still kicking around the idea of welding it, but it's not as
appealing now. The time involved alone, and the fact that I would still need
to replace gaskets, drain plug and crush washer, etc., makes me lean towards
a new pan which I know will be 100% the first go (or at least it better be).

Thanks to everyone for their suggestions and comments. 

-----Original Message-----
From: quattro-bounces at audifans.com [mailto:quattro-bounces at audifans.com] On
Behalf Of John Larson

You said:  "I was actually looking at that stuff. There are a couple of 
brands, one
being HTS-2000. <SNIP>."

Kevin

How would you EVER get the pan clean enough to weld?   It takes a LOT of 
work for my welding guy to get one clean enough OFF the car, including a 
trip through the giant mechanized parts washer, preheating the work to 
get any left over oil to ooze out, and rewashing the small area with 
various degreasers.  John