Brass on stainless beats rust

Question:

I have a recurring problem that I haven’t seen anything about in Auto Restorer or my other car magazines, so I thought you might have a suggestion. Here in the rustbelt, working on old cars can lead to a lot of cussing. When it comes to exhaust work, I am to the point that I don’t even try to remove any fastener with a wrench if it has been on the car more than a few months—I just cut it off with the trusty torch. But there are times that I would rather not. Just in the last couple of weeks I have had two cases when I needed to remove the header pipe, one on my old Chevy daily driver and another on my wife’s car. One was to replace the flange on the pipe-toexhaust-manifold connection and the other was to get the starter off. The nuts on the studs that hold the header pipe to the exhaust manifolds are always rusted in place and usually need to be heated with the torch to get them loose. And the studs often need to be replaced as well. But they always seem to twist off before they come out. So then it becomes the much bigger job of taking the exhaust manifold off, drilling out the studs and putting in HeliCoils.

So here’s the question: How do I make it last so I don’t have to go through all that the next time? Brass nuts do not rust, but the studs still rust so bad that the nuts won’t come off. Now I’m thinking stainless. Under these high heat conditions, will it do the trick? Do I have to worry about electrolysis sticking it to the iron? I found 18-8 and 316 SS studs and nuts in the right lengths from a local supplier who says the 316 is more corrosion resistant, so I will give that a try. Do you have any other suggestions?

Answer:

Brass nuts on stainless studs will solve your rust problem. And for good measure, I also suggest putting a good smear of Permatex Copper Anti-Seize lubricant on the threads. The copper-infused ver-

sion from Permatex is specifically formulated to stand up in extremely high-temperature environments. Using it on both ends of the stainless studs will make it easy to get the studs out of the manifold and the nuts off the studs.