Head gasket installation question
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From: Kannapolis NC
Header gasket installation question
I have Mr Gasket 7401G head gaskets. It's the layers of aluminum sandwiched together. I think these are pretty standard.
Does the smooth side face the heads or the manifold? Or does it matter?
I have the heads hanging on the outside 2 bolts. I read there is enough room to slide these gaskets in the gap, I am not sure if that is true or not, but I'm going to try. Just not sure which direction to slide them in. I think I only get one chance to install these right and get them not to leak.
Does the smooth side face the heads or the manifold? Or does it matter?
I have the heads hanging on the outside 2 bolts. I read there is enough room to slide these gaskets in the gap, I am not sure if that is true or not, but I'm going to try. Just not sure which direction to slide them in. I think I only get one chance to install these right and get them not to leak.
Last edited by Rob Via; Jan 1, 2022 at 09:53 PM.
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Are we talking about head gaskets or exhaust manifold gaskets??
And if we are talking exhaust manifold gaskets, if you just drop them down, how will you know if there centered properly and not partially covering the hole's??
And if we are talking exhaust manifold gaskets, if you just drop them down, how will you know if there centered properly and not partially covering the hole's??
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From: Oxford MA-----You just lost the game!!!!
A head gasket doesn't go between the head and the manifold, it goes between the head and the block. That's probably the source of your confusion. Oh, wait.....are you talking about header gaskets? In that case, yeah, smooth side toward head, get all the header bolts just barely started, and then tighten them all finger tight, then tighten them down evenly working from the center towards the ends. Don't over tighten them, 20-25 ft.-lbs. outa seal them up. You can always tighten them a little more later if you have to. In general, be careful and gentle, and you should be just fine. Good luck, let us know if you have any problems.
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OK I got the header gaskets in and got it all back together. They leak like a sieve. I put the smooth side in as suggested here. The thing is, the shape of the gasket doesn't match the shape of the exhaust manifold. I have Hooker long tube headers. The gaskets are the ones that were on it before. When I got the car they didn't leak. So I think these gaskets are capable of sealing. Is there a trick? I tightened the manifold up from the inside out. Is there a different gasket that will work better? The gasket is made like a cup and the edges are raised. When they are under the manifold, it has to crush the gasket. I'm not sure if that is right.
I have read many threads that referenced trouble getting the gaskets to seal. Is there any way to check before you put it all back together and crank it up. It's a PITA taking everything apart and back together and then it leaks again.
If I take the gasket put, is it toast? Can I try and make it seal? I bought 2 sets when I got them just in case.
I have read many threads that referenced trouble getting the gaskets to seal. Is there any way to check before you put it all back together and crank it up. It's a PITA taking everything apart and back together and then it leaks again.
If I take the gasket put, is it toast? Can I try and make it seal? I bought 2 sets when I got them just in case.
Last edited by Rob Via; Jan 1, 2022 at 10:11 PM.
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From the beginning it's sounds like you are looking for the quick easy fix. That didn't work. Sometimes it does, sometimes it bites you.
you need to pull those headers and check them for flatness. Make certain those gaskets are in the correct position before installation. Then you should have success.
trying the quick and easy way isn't always the best way.
I just replaced my manifolds with the larger 2 1/2 inch ones. Took my time and made certain that the ports matched the heads. Glued the gaskets in place so I know they are in the optimal position. No leaks.
you need to pull those headers and check them for flatness. Make certain those gaskets are in the correct position before installation. Then you should have success.
trying the quick and easy way isn't always the best way.
I just replaced my manifolds with the larger 2 1/2 inch ones. Took my time and made certain that the ports matched the heads. Glued the gaskets in place so I know they are in the optimal position. No leaks.
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From: Kannapolis NC
I wasn't looking for the easy fix. At least I don't think so.
When I got the car, the manifold didn't leak.
I had to rebuild the transmission and to do that I had to remove the headers. I painted them while I had them out. When I put them back in, I reused the old gasket. I know, not smart, but I was thinking I would have to take it off again soon because I was working on several things.
They of course leaked, but I was kind of expecting that.
So now I'm trying to get the manifold leak fixed. I didn't think the manifold was warped.
The gaskets have holes for the bolts to line them up. If the bolts don't go through the holes, it's not lined up. At least that is what I think.
At this point, I really don't know for sure.
When I got the car, the manifold didn't leak.
I had to rebuild the transmission and to do that I had to remove the headers. I painted them while I had them out. When I put them back in, I reused the old gasket. I know, not smart, but I was thinking I would have to take it off again soon because I was working on several things.
They of course leaked, but I was kind of expecting that.
So now I'm trying to get the manifold leak fixed. I didn't think the manifold was warped.
The gaskets have holes for the bolts to line them up. If the bolts don't go through the holes, it's not lined up. At least that is what I think.
At this point, I really don't know for sure.
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Well, this just isn't rocket science. so, the gaskets are misaligned, or the header flange is warped.
I would pull the headers and check for flatness. and while they are off check the gasket alignment. those bolt holes are often much larger than the bolts.
I would pull the headers and check for flatness. and while they are off check the gasket alignment. those bolt holes are often much larger than the bolts.
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I didn't think it should be that hard either. The bolts seem to thread through the gasket, so I didn't think there was much way the gasket could be out of position. My guess is the manifold must be warped some. Is that something you can get straightened, or do you have to get new headers?
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I didn't think it should be that hard either. The bolts seem to thread through the gasket, so I didn't think there was much way the gasket could be out of position. My guess is the manifold must be warped some. Is that something you can get straightened, or do you have to get new headers?
Secondly, when tightening headers, you HAVE to start with the 2 center bolts, then work your way to the end ports. It's like ironing the wrinkles out of a shirt, so to speak. And if all else fails, you can take a hack saw, and put a cut in the flanges between the center and end ports, which makes it easier to draw the header flange in evenly.
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They are hooker long tube headers. The gasket isn’t the same outside shape as the headers. I thought that didn’t seem right, but that was the gasket that was on there before and it sealed.
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Bugger of a thing to have to do twice. First thing I would do is pull those gaskets out and have a look at where and how they failed. This should give you some idea as to how to proceed forward.
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https://www.holley.com/products/exha.../parts/2134HKR
these are the closest headers I could find by the picture.
these are the closest headers I could find by the picture.
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You have to match the gaskets to the headers. See how many options there are?
https://www.holley.com/brands/mr_gas...eader_gaskets/
https://www.holley.com/brands/mr_gas...eader_gaskets/