Copper Head gasket blow-by

kuhnga

Registered User
I have copper head gaskets and the block is o-ringed(on the block side no recess). I do not know when it started,but it has been a least a few months that I have developed a leak under high boost or N2O at times. It does not happen all the time but when I beat it on the sreet or track my overflow res. will bubble and almost fill up. I assume this is combustion blow-by? somewhere?
Anyway it has not been a problem so far and I have no coolant leaks. What should I do, I would perfer to wait until winter to do any thing.

Re-torque?
change headgastets?
get rid of the copper?

Thanks
 
I had the same problem.It would only leak on start up ,when cold.
Or under boost on the dyno.I had composit gasket,so I had to change.

You may get away with retorqueing with your set up.

I would get fix before the bearings get anti freeze on them
And a rod starts to knock.

I f the head gasket surface would have some contamination
from the anti freeze or blow by carbon it may hot seat back
down with a retorque.

my .02

good luck randy
 
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Gary this is actually a common problem..I'd retorque the gaskets. Also on alot of the high HP V8 cars we run with copper gaskets we usualy run some sealer in the system as well
 
This is why I'd never go with copper in our cars. You have to retorque them. I was told by a friend at a race shop that unless I planned on re torquing them on an ongoing basis, I would be best to go with a standard gasget.
 
Gary,

I would suggest switching to the late model 4.2 liter multi-layered stainless steel gaskets. The oring grooves can be filled with JB weld and then re-deck the block and heads with a very smooth surface.

You may even get away with sanding the deck and using some spray on copper sealer if you don't want to pull the engine.

David
 
It is not a big deal to retorque them, I just wanted someone else that has experience with copper to tell me that. I will retorque them tis weekend and hope for the best.
David, from what I understand I can use the 4.2 or the regular felpro with the o-ring still there. That would be what I would try if the problem continues after re-torque.

Thanks Gary
 
Gary something I do aswell is oring the heads and use a standard felpro gasket....So I;m sure it can work the otherway around..I usually stay away from copper due to coolant leaks if I can
 
Re: Copper gaskets

Talk to Bob Johnson Racing in Cirtus Heights (Sacramento), CA.
He cuts a receiver groove in the heads so the copper crimps and really seals.
I haven't had any problems with mine...
 
Sony thats excatly what I usally do..If I have a poblem with my new motor....I might give it a try..I try to stay away from doing it however if I dont have a problem..I end up melting pistons instead of blowing gaskets..Not good
 
I debated on whether or not to cut the heads and decided not to, they cost ot much and if I would have to deck them again it might be a concern.
Thanks for all the info
Gary
 
Gary,

The symptoms you've described sound exactly like what Bill McNeil experienced last Fall with his car and the MLS gaskets. It turned out we failed to torque the ARP studs down enough, and so combustion pressure managed to bleed past (and between the layers) of the gaskets.

I suggest you deal with this before it costs you elsewhere, but based on the fact that with Bill's car, he just replaced the gaskets and went with more torque on the studs, I expect you'll have a good chance of getting away with simply re-torquing the studs.

Keep us posted!

Cheers,

Sean
 
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