Has anyone tried different methods to installing exhaust system gaskets that actually don’t leak?? I was thinking for installing 1/8 of an inch soft aluminum instead of your typical gaskets.

 

If you use silicone gasket sealant with new gaskets, you should never get a leak.

 

It’s an exhaust system it will burn any sealing compound right out, I have tried those types of sealants and they only last a day or 2

 

The right kind of Permatex exhaust gasket sealant will be able to take a lot of heat.

 

I doubt aluminum would handle the heat for long. Copper would be a better choice.

 

which permatex sealant is the "right kind"? I'm trying to deal with my exhaust leak too.

 

hmm ok so i found 2 kinds. The first one is copper hi-temp spray a gasket with temp range from -50 to 500F. The other kind is non-hardening Hylomar HPF with temp range -60 to 600F. Any idea which one might be better?

 

I Use Copper Works Very Well

 

Or...new gaskets, and good exhaust nuts? Are you guys just being retarded? This isnt some kind of joke right?

 

http://permatex.com/products/Automot...sket_Maker.htm

I use this on everything. never had a leak, never blown out or burned up. perfect seal years later.

 

lol well i mean some of us might have the misfortune of buying something like...say a bonez HF cat which has flanges that happen to not be flat (yay). Even with new gaskets I still have a fat exhaust leak.

 

nvrmind, question answered

 

The Hylomar will work well with the situation you're describing with your HF cat.

 

I've tried the various high-temp silicones. They all went to toast for me.

I've used OEM. They work but they're expensive and don't conform at all to slightly warped flanged. Stainless exhaust parts are really nice, but they don't tend to be very flat. Doubling the OEM gasket sometimes works.

Recently I'm using two new options: 1) embossed solid copper gasket by SCE gasket at my 3" 2-bolt sections. 2) compressible graphite for the downpipe gasket. I got the graphite piece from Pineapple Racing. Rob says he usually doesn't run these on stock exhausts due to the backpressure blowing them out, but I have an aftermarket downpipe and cat-back installed so I'm not quite that bad. So far so good.

Both of these new options are working well, can take up a lot of warpage, and don't cost an OEM fortune.

 

https://www.rx7club.com/showthread.p...hlight=remflex

Dave

 

^ This is the type of material I got from Pineapple.

Dave

 

How many miles do you have on this?

 

I think your prblem may lie w/ the flanges not gaskets. After time the expanding and contracting from the heat will cause the exhaust flanges to warp. The gaskests usually still seal until you take the exhaust apart and put it back together. I have had success by heating the flanges to glowing red hot and banging them w/ a hammer on a flat surface to straighten them to true. Let them cool an rehang them and it should seal fine. ( I have left the downpipe on and torched the flange right on the car. With a couple of whacks you can pull ithis off as well. ) G

 

I have a 2nd gen...but the issues are still the same.

Every time ive tried using ultra copper...it burns out right where the leak is. Stays fine on the outside of the flange, but where it needs to be, it doesnt do a damn thing.

I havent tried copper, but V bands work great. Sometimes the bolts warp though...which I suppose is why they sell just the band clamp...

What I did to fix mine is just weld everything together. I know that if its all welded then it wont leak, period. Its a temporary fix, on the stock (all 90lbs of it) exhaust. Itll get changed soon...but I need to pass smog.

I would recommend staying away from sealants though.

Heating the flange sounds like a good idea though...I might have to try that next time.

 

I do not know of ANY sealants that will hold up to the heat and stress produced on an exhaust system - period. And I wouldn't believe in any if anyone produced one. However I do believe in flat exhaust flange surfaces, new metal impregnated gaskets and some nickle-eze anti sieze lube for the bolts. This will hold and is what I run.


Later

 

About 100.

That's why you haven't heard me making any particular endorsement yet. I still have my stock gasket, so if it blows out I guess I need to spend a couple more hours changing the gasket again.

Also, as Tom has said ^, no sealant I've ever tried has even come close to working. Even at the joint in the cat-back, which should be the coolest joint in the exhaust, the 600F fancy Permatex Copper Silicone sealant burns up in days.

Dave

 

All of you guys probably have warped flanges. Those 2-bolt flanges love to warp from overtightening and aftermarket gaskets that let the ears bend.

I've had luck heating the flanges on my FC with an oxyacetalene torch, then whacking them on the ears (put a stack of nuts over studs to protect them or remove the studs) to bend them back the other way a little. My FC is finally leak free after doing this.