Cylinder head/head gasket problems

[Eyvind Spangen]

I have pulled the head on the 90q today. 4 missing exhaust manifold
studs, lots of rotten rubber hoses etc.

But the biggest problem: I can't see any defects on the head gasket..
BUT I can see a hairline crack in the head at cylinder #5.. The crack
is not between the valves.

What is possible? Can that extremely small crack cause the problems,
or is it likely that the head gasket was leaking, but not so much that
I could see it?

I'll send the head to a machine shop tomorrow to make sure it's flat
before I put it back on, if it ever gets back on.. I'll let them
pressure test it to find any possible leaks, but it'd be great to hear
something from you in here too..

I thought that the I5 gasoline engines were pretty tough, and that a
small overheat (driven 2 minutes without much coolant in -20 degrees
C) would not cause head problems..

--
E. Spangen
'86 Audi 100 2.2 CS quattro