Sucked a valve

[<DILLARDP@edu-suu-lifac.li.suu.edu>]

[Due to frank language, parental discretion is advised]

This afternoon I am going out to look at a '71 Type 2 Westy camper 
(one can never have enough of those) which, I am told, "sucked a valve"
(can they say that in Utah???).

If the body and all components other than the engine are in good shape,
I may make an offer to buy the VW.  But... as usual I often rely on the
kindness of friends...

What specifically does it mean when an engine "sucks a valve"?  Mechanically,
what has happened?

More important, if I tear the engine down, what should I expect to have to
replace/repair?  Head?  Pistons/cylinders?  Other?

Does this type of engine failure have a likelihood of damaging the case or 
the components in the case?

Anything else I should know?  (What a question!)

AOTBE, I might purchase the vehicle if the price is right.

Thanx...

Phil
dillard@suu.edu