The correct answer is flat iron to iron or steel to steel surface are mildly self binding when flat and clean because they are ferrous metals. Bet most did not know this. Years ago I saw someone actually explain this outside the academic community. This is the reason why no gasket is needed. There may be secondary reasons like heat dissapation. Unlike most headers, besides being thin metal they are stainless steel non ferrous metal and require a gasket because self adhesive will not occur.
Sand paper, level and elbow grease. It works unless the manifold is too damaged or the head too damaged.
I'm thinking they tried to mill them. They charged me anyway and I got zip...not even my cracked manifolds back. Never went there again....
Okay, but like i said before here why does a perfect original exhaust manifold without gaskets suddenly start to leak after 52 years? Is it a rust issue, wear or both?
There is nothing wrong with using a mill for this job, as always, it's the operator that makes the difference. I cannot believe they still wanted to charge you, that's insane.
Moisture. Water/moisture sitting in the seam between head and manifold. Bolt eventually experiencing metal fatigue therefore stretching cause uneven heat distribution. Or the manifolds cooled too quickly when hot like someone hosing down accidentally. Car left in extreme cold. And/Or all of the above in combinations.
The big table belt sander cleaned mine quicker than a smoke break. A few little strokes and done. NEVER leaked again.
Okay, thanks. Sounds right yes. It is just a small leak though. At first i was able to retorque the longest bolt some in the RH manifold and the leaking sound at part throttle became less. But after some more drives it got a bit worse. Don't know why ofcourse.
Just do the Remflex gaskets, no need for machine work or sanding. I had a set of cheep headers on a SBC and every 6 months the one header gasket would start leaking. 3 years of that then I went to a Remflex gasket and it’s still leak free 14 years later! It just isn’t worth the hassle trying to go gasket free, eventually something will warp and leak. If it’s factory and not leaking leave it alone but once it leaks just use the right gasket and done. Plus you never ever have to re tighten the bolts and the reflex of the gasket rebounds and holds it tight so it won’t rattle loose. Only 22 foot pounds on the bolts and then no need to re tighten for 10+ years. No locking bolts needed. No leaks. They conform to the imperfections.
You are right but i don't like the look of it. The engine has never been worked on and i like to keep that look. Also i need to do the RH side only at the moment. I probably will go with another gasket or even only permatex or what we have here Holts.
You are right again We'll do a good cleaning ofcourse and probably will go with fel-pro gaskets. I used them on another 430 and for plenty of years no leaks. Anybody here has a picture of Remflex gaskets installed on a 430ci with stock exhaust manifolds? Maybe i could go that route if it does not look too bad lol.
I've done plenty of manifolds where I only flatten out the manifold side, and they are fine. But it's up to you. I get tired of this debate.
I'm a gasket guy don't want to be pulling a manifold or snapping stripping them bolts to close a leak if my filing is off.
I used anti-seize full length on all the bolts after surfacing the manifolds. I also removed the heat riser valve, to insure against super heating the manifold. And got rid of the laminated exhaust piping that colapses internally and super heats the manifolds, and installed solid 2.5" pipes. Don't park in a garage that sweats or everything will rust except your anti-sieze coated bolts. Just some thoughts from 50 years ago.... But what got fixed, stayed fixed, or I was just lucky.
That's what I did when I did mine back in 2017. I set up the heads and the manifolds on a Bridgeport and milled them flat. No leaks. The heads are extremely easy to do. The manifolds are trickier to set up to flycut.
