This is a tale of two heads ;-).

The usual coolant leaking problem occurred at 110k miles on an 85 
Vanagon.  Stop leaks worked for awhile.  Decided to bite the bullet at 
139k and replace them at my convenience rather than the van�s.  Asked my 
repair shop to order the rebuilt heads ahead of  time to minimize my 
down time.

The heads arrived but the shop owner was concerned that there may be 
some cracks in the heads.  He said the area between the valves or near 
the plugs was where he has found them before.  Cracks in this area are 
an early step to dropping a valve into the cylinder,  very bad 
happening.  Under a magnifier there was one suspicious area between two 
of the valves but it was not obvious.

I suggested he dye check them;  a new concept to him.  I sent our 
materials engineer, a friend, over to show the shop how to do this very 
inexpensive check.  It showed cracks between three of the four valve 
pairs.

He sent the heads back.  You folks on this news group had warned me to 
watch out for cracks in rebuilt heads.  Thanks.  He found some new heads 
for only $100 more each.  Considering the cost of the job this seamed a 
good investment.  (I know cost, time and available resources may be 
different for each of us.)

New heads are on, working fine.  Happy ending to the tale.  It might not 
have been except for this news group and a concerned repair shop owner 
who values my business.  Wouldn�t it be nice if dealers really thought 
and acted that way also.  But then, the great independent shops would 
have less business.  Not good.

Larry