What's the best exhaust manifold gasket to use

[Jim Mills]

I've got the infamous exhaust manifold leaks in my 07 4.6 and I'm curious what the best gaskets and bolts are to replace them I have the job scheduled for Monday morning and hopefully the aftermarket warranty company will cover everything. thank you

 

[Robert Caffyn]

As of today, my mechanic removed the exhaust manifolds, had them planed smooth. I found a multi-layer gasket from a company named "Victor Reinz", the gaskets are available from AutoZone(they will probably have to order them). Reassembled everything today with the new "upgraded" studs from Ford(some have been changing these to grade 8 bolts). Used a bead of copper permatex on both sides of the gaskets and torqued all to spec(18.5flbs). As of 6 hours ago there were no leaks. Let you know, Bob

 

[scott degroot]

The factory gaskets never let loose...it's the bolts breaking that is the problem. Get the updated bolts and use factory gaskets AND NEVER APPLY ANY TYPE OF SEALANT TO THE SURFACES as it can eventually interfere with the sealing. Victor Reinz gaskets...I will not use them as I have been stung too many times by them

 

[Robert Caffyn]

Well lets see. Have had 3 sets of Ford gaskets pit in, along with all of the new upgraded studs/nuts from Ford and it still leaked. Had the manifolds planed off, it still leaked. So frankly the Ford(and Fel-Pro) gaskets suck! Nuf said. Bob

 

[A1cntrler]

It was a problem with the manifolds warping and snapping the studs off, not really a problem with the gasket. I had both manifolds replaced and all studs replaced on mine, but it was all covered under warranty. Since I had it done I haven't had a problem yet, but it made it to about 60k before I ever had the problem to begin with. I am not familiar with the gaskets you mentioned, so I have no opinion of them, but I do agree with the statement about not using any kind of sealant on the mating surfaces.



All you did was plane the old manifolds, not replace them? Did everything still line up correctly even though they were warped? I wonder if it was the material the original manifolds were made of that caused them to warp and break the studs off?

 

[scott degroot]

Bob



I have a feeling that with your modified exhaust system that something else is going on. Is it poossible that there is some slight movement in the exhaust system since you redid it that is causing undue stress at the manifolds and therefore causing them to leak or perhaps the exhaust doesn't fit quite right and needs to be "helped" into place which could also casue undue stress at the manifolds (most people don't think about the later issue causing a problem but it can)

 

[Robert Caffyn]

Didn't mean to sound rude. I apologize. But this all started back when I still had the "stock" exhaust! I don't know, I may have to eventually spring for new manifolds? Keep you posted. Bob

 

[EddieS'04]

I have used the copper rtv on most all exhaust gaskets for years.

Just my personal experiance. It never caused a leak.

Another expeiance has been, with headers. Identical headers gasket and bolts. Friends developed leaks and I didnt.

My brother couldnt get the right bank exhaust manifold to seal. This was a ford 390 FE block. The copper RTV sealed it. Until he sold it 6yrs latter.



So is copper RTV experiance, opinion or knowledge.?

 

[Jim Mills]

Wow guys, didnt mean to start a feud here, just trying make sure I only do this once. Just found out that Ford updated the gasket according to my Ford parts guy. I may try to get the manifolds themselves covered since its a warranty deal. Thanks for the input & good luck with yours Bob.

 

[scott degroot]

Don't worry you didn't start a feud.



Eddie



While I have personally never used copper rtv on anything I have seen it used alot on exhausts when people come in to have the exhaust leak fixed. I can honestly say that I have never had an issue as long as the manifolds were straight and the hardware was in good condition, IDK maybe I am just abnormally lucky.



Here are my thoughts on sealant..if it didn't come that way from the factory why is there a need for it now? Obviously this is in regards to modern day engines.

 

[EddieS'04]

Scott,

I used to blowout header gaskets. Before I started using it. I never bought headers that had a flange per port. I would buy headers with 3/8" plas-arc cut. Every port was on the same flange.

Single port flanges warp. Then hard to line them back up. Last motor I built was a '94 cobra 302 roller tappet push rod.

So I cant say I have used it on anything modern. I had a set of SSI copper gaskets. I was going to try them next time. I sold the 'stang, so next time never happened..LOL



My brothers issue. Despite machine matching the head and manifold. It still blew the gasket. He broke a couple of studs. So the head had to come off. It was a '73 truck with a 390fe. Came from a mid '70s galaxy Most likely a lousy machining. The copper rtv fixed the leak, permantly.



Never tried it, but. Some have said if you parts a true. The copper rtv works without a gasket. I have seen alot of after market parts, come with the specific rtv, no gasket.

 

[scott degroot]

I must be the luckiest SOB in the world...off to Vegas I go.



Various Ford engines over the years didn't come with exhaust manifold gaskets from the factory and yet never leaked, kind of makes you wonder doesn't it. Another big issue that most people don't think about when it comes to manifold leaks is whether or not the port on the manifold is larger or smaller than the port on the head. Surprisingly alot of older vehicles had manifold ports that were smaller than the port on the head, and even alot of cheap headers, so that always leads itself to eventual exhaust manifold leaks.

 

[EddieS'04]

I remember those days of oem without E-manifold gaskets. Rebuild kits came with gaskets, though.

I think your right about the lack of port sizing, the exhaust ports. One for sure, is the pushrod 302 ford. Oem headers were pinched. Compared to the port on the head.