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Head gasket on o-ring'd block question

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FLASH1970

15+ Year Contributor
1,264
11
Aug 22, 2005
Lake Geneva, Wisconsin
I have a question for all you guru's. I am rebuilding my first 4g63 engine. It is a 2.3 stroker with Ross .030 over pistons and Mitsubishi MLS headgasket I am re-using. First I cleaned the headgasket up and sprayed it with copper spray. But, the block has o-rings in it. The machinist said there might be something extra I have to do seeing that it's o-ring'd. Is there anything special I have to do when putting on the head gasket? Thanks to all in advance.
 
No, but I also wouldn't reuse a head gasket. Head gaskets are made to kinda flatten down a little when torqued, to make a perfect seal, reusing a head gasket usually isn't a good idea because you are not going to get that even, perfect mating like before.
 
You need to use a new headgasket! Use a cometic mls or a OEM mls tthey are only like $90, dont skim you will regret it in the long run ;)

Sorry for the double post.

When you have a oring anything, block or head they will use eighter a copper oring or a metal one, if they have a metal one you are suppost to use a copper mls, and vise versa, with a copper oring you are to use a metal mls.
 
Wow, I'm surprised every one said go with a new headgasket. I've heard multiple times that people reuse MLS headgaskets as long as they aren't trashed. I have copper o-rings so I guess I'll look for a new steel MLS headgasket (that's what was on there). Thanks everyone.
 
When your block is O-ringed you have to use an O-ringed head gasket.

FFWD Connection - Race Injuns That Will Freeze Your Brain

The O-ringed head gasket is on the bottom. O-ringed head gaskets literally have a metal O-ring in there that when you torque down it crushes it to create a solid seal. Reusing an already crushed O-ring would be very detrimental to you. Make sure it is O-ringed though because your block actually will have rings it it from the head gasket being there. They should be groves big enough to fit an edge of a quarter in there.
 
When your block is O-ringed you have to use an O-ringed head gasket.

FFWD Connection - Race Injuns That Will Freeze Your Brain

The O-ringed head gasket is on the bottom. O-ringed head gaskets literally have a metal O-ring in there that when you torque down it crushes it to create a solid seal. Reusing an already crushed O-ring would be very detrimental to you. Make sure it is O-ringed though because your block actually will have rings it it from the head gasket being there. They should be groves big enough to fit an edge of a quarter in there.


My block has copper o-rings pressed in it that stick out a little bit. I just want to get the right headgasket to work properly with them. Not sure if you understood that. I went to the link and it said the o-ring headgaskets t the bottom are not to be used with o-ring'd blocks.
 
My block has copper o-rings pressed in it that stick out a little bit. I just want to get the right headgasket to work properly with them. Not sure if you understood that. I went to the link and it said the o-ring headgaskets t the bottom are not to be used with o-ring'd blocks.

the very bottom one says it IS to be used with o-ringed block and heads
 
the very bottom one says it IS to be used with o-ringed block and heads

Yeah, my web browser stuck for a moment so I thought that was the last gasket. LOL. But, it does say to use them with stainless steel o-rings. I have copper o-rings in my block...
 
What Defiant said.
But as a guy with some experience on o-ringing blocks (diesel machinist for 12 years), I will say you need to do your HOMEWORK, there are different ways of o-ringing a block so you must make sure you stick with the method it was done, everybody is throwing in some opinions and none are wrong. You just have to make sure if it was designed for a special H/G or some cases you use a copper gasket that actually squeezes down into the groove), some don't even use head gaskets and have copper rings around the cylinder and rubber o-rings around the water ports! TALK TO YOUR MACHINIST
 
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