>>>1.  What are the probable causes for 0 compression in #2?<<<<

Cause!
Well, first look at the most commun problem on Air-Cool engines:
http://www.benplace.com/head/heads014.jpg
http://www.benplace.com/head/heads011.jpg

result:
http://www.benplace.com/head/heads016.jpg
http://www.benplace.com/head/heads017.jpg

Head fnish/ kapout:
http://www.benplace.com/head/heads019.jpg

Yea, it could be a piston, rings or gasket (leak down test will help
telling), but IMHO, heads are the big problem.

My suggestion: Find 2 good head core (or 1 if the other one is good, and
maybe both are still good), have them rebuilt by a "pro". There is some very
good machine shop that can replace or/and weld the new valve seat.

Now, the reason: Bad valve adjusment or in your case, a faulty lifter????
Or just a history of engine overheating. But if only one cylinder is dead, i
would suspect a faulty lifter or/and bad valve adkustment (even with hydro
lifter you can easily be to tight).

In my case, 3.5 cylinder were cooked, the PO was a young guys with that
didn't know what the word "Maintenance" was. Valve were adjusted every 5000
to 7000 miles... Both heads were cook due to poor fuel mixture, bad valve
adjusment, poor maintenance. The heads were only 3 years old.

I have learn a lot in the pass year about air-cool engine, the hard way.
I think that if you can keep the heads temp around or under 375F, oil temp
between 180 - 220F, good plug, good mixture, good ignition and drive this
one at 60mph max... the engine could last for a long time. But hey, we
didn't buy those van just to wonder about the engine condition all the
time... did we?

Like others said, if the case is warped... that's another story.

My VW Westy engine conclusion:
Vanagon AC & Bus: Deal with heat, oil leak, heavy maintenance and under power.
Vanagon: Deal with coolant leak, and a somewhat complex mechanic.

Why the hell do we own and love those van, that is the real question.

I do long run/ drive with my westy, on the 73, to keep a 360-380F head temp,
i have drive under 60mph, more exactly, 58mph. I did some testing with
infrared temp gun wile running.... well, i should do a post about that!!!!

Good luck
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