[Vwdiesel] Coolant leak

[Bud]

Started getting a coolant leak about a month ago (1k miles).  Couldn't tell
where it was leaking until this morning when I started it up cold.

On the back of my 85 1.6L Golf head (drivers side), there's an inconsistent
leak.  But I'm not sure if it's the head itself or the coolant flange that
ties into the heater core in the passenger compartment that's weeping.

I opened the expansion tank and fitted a nitrile glove over the opening and
sealed it with a rubber band.  The glove did not inflate it actually was
sucking into the tank a bit.  There is no coolant in the oil that I can
tell and when I rev the engine I just get the normal black smoke or the
grayish smoke of unburnt fuel at startup.  No white clouds.

I'm kind of leaning towards a bad seal on the coolant flange weeping along
the head joint.  After a minute the weeping stops and the coolant has dried
up.

There's 165k miles on the rebuilt head and stretch bolts I have in there
since my limited rebuild.  I have no overheating other than twice my gauge
went erratic and then I saw the coolant was real low in the expansion tank,
but still enough to cover the head and I just filled it up with water.

Is there a life expectancy on the head gasket and stretch bolts?

Thanks,
Bud
http://www.rhinocat.com/cvaf4u/