Check out Jeff's web-site (vanagonparts.com).  He has a section called
Technical Bulletins, and one specifically addressing this problem.  P.S.
He's a good guy.  Help support him and buy some stuff from him.
http://www.vanagonparts.com/home.html

----- Original Message -----
From: "Matt Sutton" <msutts@EARTHLINK.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, December 28, 2004 11:59 AM
Subject: Re: Help! Massive oil leak from behind cooler (2.1)

> Hi folks,
>   Thanks for all your tremendous help. The leak is fixed, I just got home
> to Brooklyn with no problems, and none of this could've been done without
> your help.
>   I found the O-ring at a dealer in Warington PA, it looked very different
> from what it replaced: Not gray as some had mentioned in reply posts, but
> much beefier than the original and with two tab-like protrusions on the
> inner circumference that  that grabbed onto little barbs on the mating
> face
> of the oil cooler.  Anyway- it seems to have done the trick, and I've
> lightened the oil weight from 20w50 to 10w40, which makes the cold starts
> a
> lot easier.
>
>   Thanks so much to this list for bailing me out again!
>
> -Matt Sutton
> 88 GL
> Brooklyn NY
>