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Install exhaust mani gasket backwards?

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I don't believe it's possible to install that gasket backwards. Did you torque the nuts down fully after heat cycling the gasket?
 
Hasn't even been cycled yet LOL Theres other issues and its running like shit but I could feel room temperature air coming from the #1 cylinder runner by the head

its also worth noting I just had my head off to weld then tap the right most stud because it was stripped so bad
 
Sanding is an easy way to get a non level surface too.

The manifold has been torqued and is still leaking. Is it a cast or tubular manifold? I I would at tg least check ygr manifold flange first for straightness before blaming the head.


What portion of the head was welded and who did the work?
 
tubular mani. Trust me, I spend hours making sure that was flat. The work was done by a guy who I would consider to be a professional but who knows. The right most stud hole on the bottom was filled in a retapped so a new stud could fit in.

The stud thats the right most on the top had a broken stud in it and he got that out and retapped it. I have no idea if he decided to completely drill that out, weld it, then retap it though.

all the other studs were still in place when he did this so he couldn't have gotten the entire thing level, when I think about it.

Problem is I don't want to have to get another gasket so I wanted to leave it in place. And when I remove the studs, I'm worried I'll take some material with it and then they will strip when they go back in. Any thoughts?:hmm:
 
tubular mani. Trust me, I spend hours making sure that was flat. The work was done by a guy who I would consider to be a professional but who knows. The right most stud hole on the bottom was filled in a retapped so a new stud could fit in.

The stud thats the right most on the top had a broken stud in it and he got that out and retapped it. I have no idea if he decided to completely drill that out, weld it, then retap it though.

all the other studs were still in place when he did this so he couldn't have gotten the entire thing level, when I think about it.

Problem is I don't want to have to get another gasket so I wanted to leave it in place. And when I remove the studs, I'm worried I'll take some material with it and then they will strip when they go back in. Any thoughts?:hmm:

What brand of tubular header are you using? If it is anything cheap than it is likely warped.

I don't believe it's possible to install that gasket backwards. Did you torque the nuts down fully after heat cycling the gasket?

correct, the spacing on the bottom bolts only allow it to be installed one way.
 
Ebay header but I made sure to make the flange flat.

Anyways is the part on the copper gasket that sticky out around each header suppose to face toward the head or the manifold?

The gasket only goes on one way, so what ever way it fits that is how it is to be installed. The lower bolt spacing on the outer 2 holes is different so it won't on the wrong way.
 
Depending on how bad the gasket is you may be able to reuse it, I would for sure take it off and figure out your problem though, then you can check the gasket.

The manifold flange was probably flat like you said, but now it is not flat since you bolted it down to a non flat surface.

x2 - Yea my exhaust manifold gasket will only install one way.
 
The gasket only goes on one way, so what ever way it fits that is how it is to be installed. The lower bolt spacing on the outer 2 holes is different so it won't on the wrong way.

However, he did use a copper gasket which could have been put (forced) on. With the MLS gaskets it's possible to to start them on but the actual fitment is not there. I'm not familiar with using the copper gaskets so it's really all in the OPs field for how it was put on.

I still believe the issue is still the result from a warped surface.
 
Ebay header but I made sure to make the flange flat.


How exactly did you make sure the flange was flat?

I had to mill/belt sand the flange on an ebay o2 i bought once. It was extremely warped, unusable really, right out of the box.

You get what you pay for.


Anyways is the part on the copper gasket that sticky out around each header suppose to face toward the head or the manifold?

Has there been port work done? Maybe the ports are larger then the gasket? or misshapen?
 
However, he did use a copper gasket which could have been put (forced) on. With the MLS gaskets it's possible to to start them on but the actual fitment is not there. I'm not familiar with using the copper gaskets so it's really all in the OPs field for how it was put on.

I still believe the issue is still the result from a warped surface.

My bad I should have said, but I was taking about the 4 layer stock evo copper manifold gasket. That's the one I installed and it forsure can only be installed one way.

I agree problem is from warped surface.
 
Do you think its possible that bottom of the head is warped? I haven't had a chance to really run the car at all and won't for probably a month so I won't know if its leaking.

This is assuming that the manifold isn't warped and the head is
 
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You could just pull the manifold and check for yourself. Why the head wasn't checked after welding is beyond me.
 
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