You have another head gasket (internal) blown.  Have your mechanic use
his "sniffer" on the coolant.  It will detect hydrocarbons, indicating
the failure.  I don't know about the heads, but somebody is doing
something wrong here.  A bad o-ring at the bottom won't lead to coolant
pressurization, only leakage of coolant into the case.  You might check
that they are using a bar type torque wrench to torque the heads to 37
ft-lbs, and that they are using new gaskets each time they replace the
heads.   Bring your copy of the Bentley in with you!

Good luck!

Tony Peet wrote:
>
> Hi Folks.  I need your help TODAY with a cooling system problem that is
> somewhat baffling and very frustrating. I appreciate whatever time you could
> give this right NOW.  Thanks!
>
> When we took the cap off
> the main coolant tank, there was a lot of pressure released in a woosh and a
> heavy smell of engine oil......
>
> WHAT I NEED FROM THE LIST ARE ANY SUGGESTIONS FOR WHAT THE PROBLEM MIGHT BE
> -- EXCLUDING THE HEADS SPECIFICALLY.(Unless you know of a recurring problem
> with AMC heads specifically.)
>
> DOES ANYONE HAVE EXPERIENCE WITH THIS PROBLEM AND/OR KNOW OF SOME OBSCURE
> BUT COMMON VANAGON QUIRK THAT COULD BE CAUSING THIS?  ANY UNUSUAL/USUAL (!)
> FIXES ON VANS WITH THESE SYMPTOMS?
>
> FOR EXAMPLE, my mechanic's current thinking is that the O ring at the BOTTOM
> of the cylinder might be the culprit.
>
> I very much appreciate your time in considering this and in replying as soon
> as possible( the van's in the shop!).
>
> Tony Peet
> '91 Syncro Westy
> Pacific Grove, CA
>
> ______________________________________________________
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--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext. 8208
Fax: 206-269-6360

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