--- "Wetzel, Scott" <scott.wetzel@MSO.UMT.EDU> wrote:

....

 > haven't driven the van in about 2 weeks
> and when I left home, a sticky lifter was making
> noise (as usual when the van sits for a while).
> After about 10 minutes of driving in very light
> traffic in town (about 3 miles), the noise got
> louder and a more pronounced clunking noise was
> present and then it started to lose power.  I turned
> back for home, but the condition deterioriated with
> a sort of backfiring sound and some metallic
> clunking. It sounded like there was no exhaust on it
> with a clunking .......

> I restarted it but
> the clanking was still there and the engine would
> jerk violently once each time it made the
> backfire-like noise (it wasn't backfiring)

Hi Scott.

From what I can tell, the problem is likely related to
a valve, valve seat, lifter or push rod.

Could a cracked head be the sound of "no exhaust"?
Anyone?

Pretty sure that at the very least you need to remove
the head and have a look.

Cheers, and best of luck.

Neil Nicholson.
1981 Air Cooled Westfalia.

http://web.mac.com/tubaneil

TUBA TUNE OF THE DAY!

http://web.mac.com/tubaneil/iWeb/Site%205/Tuba%20tune.html

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