The O-ring is dead. See 17.7 in the Bentley Bible, which says that
after 2/87 a new cold-resistant seal was used in that spot.

You'll have to replace that o-ring. Replace the cooler hoses and the
two oil pressure switches while you've got it drained. They're
cheap. :-)

(Don't ask me how I know the Bentley book says that...)

On Jan 26, 2007, at 2:37 PM, Automatic digest processor wrote:

> Date:    Fri, 26 Jan 2007 16:45:50 -0500
> From:    Richard Golen <rgolen@UMASSD.EDU>
> Subject: Puking Oil from Oil Cooler
>
> Hi,
>
>
> Today, the temp here on the seacoast of SE Massachusetts has been in
> the teens, actually this am it was zero!
>
> I went to take my 87 Westy out for a little drive this afternoon, and
> as I pulled out of the parking spot, I noticed a large puddle of oil
> where the van was parked. I crawled under the engine and noticed that
> the oil was coming out of from between the oil cooler and the
> engine block. [..]