It could be either a broken valve or a collapsed/sunken valve seat. If
the valve broke and the head fell off, you have to hope it put a whole
in the piston. If it fell to the bottom before impact, than the strength
of the piston wall will usually result in a bent rod or cracked engine
case. The cause is excessive heat which causes both the loose valve seat
or the valve to break at the end of the stem. Although it is possible to
pull the head with the engine in place, it is easier to remove it since
all of that tin has to come off. If the valve did break, the case has to
thoroughly inspected/measured for cracks/warping.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
Of jon
Sent: Saturday, August 02, 2003 1:18 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Cause of broken valve?

My Type IV has an apparently broken valve on cylinder 1. The valve
spring
is all the way against the rocker arm. So, that leads me to beleive the
valve stem is broken somewhere, and the piston just shoves the valve
back
down. (So, I am hoping there is no further damage).

Anyone have any thoughts on this? Advice? Prayers? :-) What is the
number
one cause of broken valves on a Type IV? You'd think it would be rare,
with hydrualic lifters and all that.

It's not a real big deal, since I got this westy for essentially
nothing.
If I have to put some $$ into the engine, so be it. But, I'd rather have
it be a simple, cheap problem.

I am going to drain the oil in a bit to check and see if there are any
metal particles in the oil. Of course, I hope not. Compression on the
other 3 cylinders is a bit above 120, which I understand is good. The
engine is pretty clean, and when I removed the cylinder head covers, the
heads look pretty darn good. So, I hope this engine is savable without a
rebuild.

Jon