Thanks Joel, and please don't note the time on this one lest
I stand accused of undue nerdliness... :{)
> 
> On Tue, 6 Sep 94 20:22:22 CDT Chris Getschow said:
> >So to get to the point:  how does one definitively diagnose a head
> >gasket problem?  Without $helling out big buck$ to a VW mechanic,
> >that is...
> 
> well ... this is what vw says:
> from Service Bulletins, Model Year 1987
> A slight "internal" compression leak into the coolant system of a water-
> cooled Vanagon is not always easily diagnosed.  But what your customer
> tells your Service Advisor may be very helpful to pinpoint such a
> problem:
> *  Temperature gauge needle moves into the red
> *  Very little or no heat output
> *  Coolant refill tank overflows
> *  Air in the coolant system
> 
Sorry to you-all for quoting so much but I'll try to balance it out with
my own verbosity. :{) 

VW's official opinion notwithstanding, I am not terribly convinced that
this particular service bulletin goes too far towards eliminating those
more benign causes of coolant system problems; namely the miles of hoses
we have to contend with.  Seems to me that a small leak in a hose or at a
junction could result in the same symptoms indicated in the above service
bulletin.  It also seems to me that by issuing such a bulletin, VW must
have been attemping to cover for what is now widely acknowledged to be
a substantial design flaw in Vanagon engines by pointing directly to 
head gaskets as the source of coolant leaks.  Sorry if I'm slow on the
uptake here but sometimes the obvious requires stating.

But my practical question still stands:  when do you *really* know
that you have to tear down your engine to fix a coolant leak?
-- 

Peace.

-cg :{)