[Roadsters] OT: Funnel head gasket leak test?

[dave]

I'm with Eddie (and others)on this one.  Bubbles mean that there are
bubbles, no idea where from.  A head gasket leak MAY produce bubbles, but
bubbles don't mean the head gasket leaks.

Any competent professional mechanic has a cooling system pressure
tester...Even I have one, and I'm competent :)

Diagnostics 101
You put it in place of the radiator cap, pump it up to 17 PSI, and if the
pressure drops, take out the spark plugs, remove the oil cap and find the
coolant leak.  If it's the head gasket or a cracked head, the coolant will
come out somewhere, intake, exhaust oil pan or combustion chamber(flow out
the sparkplug hole).

If it holds the pressure, no head gasket leak, at least to the cooling
system. 
 Next step, put 150psi of air into the cylinders one at a time at TDC, THEN
you look for bubbles in the radiator, then listen for air hissing  from the
oil cap or hiss from intake or exhaust.
Pretty straight forward stuff

Dave Brisco
ECR

-----Original Message-----
From: Eddie [mailto:eddietude at socal.rr.com] 
 POTENTIAL Signs of a blown head gasket:

1) Air bubbles in the coolant
2) Coolant in the oil.  (looks milky due to the engine parts "stirring" 
up the mix))
3) Oil in the coolant.

4) Car overheats  (due to coolant level dropping)
5) white exhaust (water vapors in the exhaust smoke)
6) coolant level drops over time and needs to be refilled, but there are 
no external leaks.

Bubbles alone in the radiator do NOT mean it has a blown head gasket, 
but that it COULD have one.

Eddie