Need Info on correctly sealing a copper head gasket with o-rings

[kemicalx]

any information on using o-rings with a MHG would be greatly appreciated, as i was always under the impression o-ringing was strictly for copper head gaskets.

[7mSupra]

Do u have to run O rings on a copper gasket? will there be a problem if you dont?

[kemicalx]

afaik if you weren't going to run o-rings with a copper gasket you're better off with something like a cometic metal head gasket, Due to the fact that copper can have difficulty sealing the oil and water galleries, without o-rings you run the risk of some nasty damage in the event of leaking.

[ed]

you must use orings on a copper h/g - the o-rings provide a fire ring seal without which the process is completely pointless.

laminated steel h/g have pressings which increase pressure and produce a fire ring seal thus dont use o rings. using o-rings with a MHG that wasnt designed to use them is a bit dumb me thinks.

please seach for this topic for further information

[7mSupra]

I got told that my copper headgasket diddnt need O ringing. So it was put together. Its done 3000 k's still running the motor in so not thrashing it.
Willl my headgasket give way soon? Or should i just replace it before anythoing happens?We used ARP head bolts and the copper spray.

[ed]

was it just flat annealed copper without embedded fire rings?

annealed copper without some kind of fire ring is like play-dough. the point of the o-ring is to provide a ring of significantly increased clamping pressure, and it also bites the copper, preventing it from migrating outwards under pressure.

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[7mSupra]

well looking at some photos i have, it seems that there is little lips around all the cylinders and water galleries. do you think this is enough?

[terryo]

I do this sort of work regualrly. o rings should always go in the block so they dont need re-working each time the head comes off and is refaced. The purpose of the o ring with a stock type gasket is to exert a tiny amount of extra pressure on the gasket fire ring. that is why each job is dfferent, you have to look at the gasket design to decide how much to make the o ring protrude and where to put it. Some head gaskets have a fire ring so narrow, this wont work.
I've also seen O ring jobs get it all wrong with the o ring overlapping the fire-ring (not concentric) and this creates more failures
Some high performance blocks come with an o ring groove at the top of the bore. these use a special gasket with 2 fire rings, and one gets squashed down into the step.

Copper gaskets were originally intended to help with regular head removal on old cast iron heads/blocks. Many people have given up with them on alloy headed engines, because of the differential expansion between the 3 different metals. I would talk to the maker of the gasket about the need or otherwise for an o ring.