Could be that a valve seat has come unglued and therby unseated. This
happened to me in my 85 (water cooled). Sudden dramatic loss of power and a
sound that was similar to a hydraulic valve lifter that has drained dry. In
my case it recovered several times over a 7 hour drive,( we assume it
re-seated temporily then came unseated again) but finally the symptoms came
and stayed. Cosquence was a burnt piston. At that time the most sensible
thing to do was to replace the engine with a factory rebuilt. I'm told the
costs has since doubled.

This is just a possible explanation. Sounds like you'll have to pull it
apart to see.
Alan
----- Original Message -----
From: "Dennis Haynes" <dhaynes@OPTONLINE.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, August 16, 2003 8:57 PM
Subject: Re: Some basic TypeIV engine help, please

> Assuming that the engine was in good shape before the trip (who knows)
> it sounds like the engine was pushed too hard for too long. It is common
> for these engines to fail after long trips. The next step will be to
> check the compression to determine the extent of the damage. The
> depression on the back of the valve stems is the result of too many
> miles, cheap valves, or excessive heat. After overheating of this type,
> the case will have to be checked for straightness. If the head gaskets
> failed, a common cause is case warpage which results in the cylinders
> not being level. Replacing the gaskets or heads with out correcting this
> will only result in quick failure again. My guess is that this engine is
> ready for an overhaul.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
> Of Tom Young
> Sent: Saturday, August 16, 2003 3:02 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Some basic TypeIV engine help, please
>
> Hi all:
>
> Last night, I guess about 3:00AM, a friend of my daughter parked her '78
> Westy in front of our house, having driven from Bellingham, Washington
> over
> the course of 3 or 4 days.  I had heard that "along the way" she had
> been
> having engine problems, though what I heard was the engine was leaking
> oil
> and the right-side pushrod tube oil seals had been replaced somewhere
> around
> Eureka, California.  Of course, now that the vehicle is in my driveway,
> things are much worse.
>
> Talking to my daughter's friend I'm told that the mechanic that replaced
> the
> right-side pushrod seals told her that one of the valve stems on #3 -
> don't
> know which one - had worn concave.  During the trip from Eureka to the
> SF
> Bay area she had to stop and put in a quart of oil every 15-30 minutes.
> She
> also reports that a few miles from the house she experienced a
> significant
> decrease in power.  When I started it up this morning it was hard to
> keep
> running, had virtually no power - I'd guess it's running on 3 cylinders
> -
> and blowing smoke badly, which the friend says is new.
>
> I don't want to deal with this right now, but I guess I have to since
> she's
> here and has no money.
>
> Anybody have so good "over the internet" diagnosis here?
>
> Thanks!
> ---------------------------------------------------------------
> Tom Young                       '81 Vanagon
> Lafayette, CA 94549         '82 Westfalia
> ---------------------------------------------------------------
>