[Vwdiesel] Head gasket question

[mark shepherd]

Doyt,
He could be right about the head, but 10 to 1 he's wrong. Think about it; 
from what you said your headgasket gave you temporary relief. Or did it 
never stop? If it did then it can't be cracks because the gasket doesn't 
cover them.
The VAG genuineworkshop manual of 1982 says
"Cylinder heads with cracks between the valve seats can be used without 
reducing engine life as long as cracks are small and not over 0.5mm wide"
Thats not to say that the head doesn't need flattening, but I'd look 
elsewhere.

If you have the head off then try syringing kerosine into the cracks and 
check for draining into water by adding some and pouring into a container so 
that you can see the stuff floating...

Mark

----- Original Message ----- 
From: "Doyt W. Echelberger" <doyt at buckeye-express.com>
To: <vwdiesel at audifans.com>
Sent: Friday, September 12, 2008 12:51 PM
Subject: [Vwdiesel] Head gasket question


> Last year My 85 Jetta TD got a new head gasket, because oil increasingly
> showed up in the plastic overflow reservoir, and a little coolant was
> disappearing every week in some mysterious way . I figured the oil was
> coming from a leaking head gasket, and the coolant was part of the same
> problem.
>
> When we had the head off, we inspected the head, with special attention to
> the spaces between the valves. We saw little cracks in each of the 4
> spaces. List consensus was that the cracks were present on all the heads 
> of
> the model, were superficial, and actually meant nothing in terms of 
> leaking
> of fluids or gases between systems. Some owners peened them shut, some 
> just
> ignored them.
>
> My mechanic though differently, and held to the idea that I needed a
> replacement head.
>
> I chose the path of least dollars and elected to put the head back on, 
> with
> a new gasket.
>
> The engine ran fine when reassembled, but over the next few months the 
> rate
> of coolant disappearance gradually increased, and the engine operating
> temperature also gradually increased.
>
> Last month the pressure in the coolant system went way up and blew a hole
> in the plastic coupler of the multi-branched coolant hose at the left of
> the injector pump (left, as you stand in front of the radiator and
> look  into the engine compartment.)
>
> After the engine cooled off, I repaired the hole in the coupler (with
> epoxy),  put in new coolant, and started it up with the cap off the 
> plastic
> overflow reservoir.  A thin stream of tiny bubbles showed up in the 
> coolant
> coming into the reservoir.  I figured this is leakage between a cylinder
> and a coolant passage.
>
> After we pull the head and look at everything, my mechanic is sure to say
> that I need a new head because the cracks between the valves are probably
> responsible  for the gases leaking into the coolant. He said that the last
> time. And new heads are very costly. Do you think he is right? Any way to
> test the cracks to see if they leak?
>
> OK, so I'm back again, asking for input. All ideas are appreciated.
>
> Doyt
> Ohio, USA
>
> _______________________________________________
> Vwdiesel mailing list
> Vwdiesel at vwfans.com
> http://www.audifans.com/mailman/listinfo/vwdiesel
>
>