Exhaust: Brass exhaust manifold nuts

[PackardV8]

At a local estate sale, I came across a box of 3/8" brass nuts and another of 7/16" brass nuts.

I notice the SI exhaust outlet flange kit has brass nuts, but can someone refresh our memory of which Studebakers used brass nuts on other areas of the manifolds? We encourage customers to send us stripped long blocks, so I've sort of forgotten where brass nuts might have been OEM.

jack vines

[Alan]

On the 2 studs on the end of the exhaust manifold to head pipe and the heat riser valve.

[Mike Van Veghten]

Agree, that's one place I've seen them, the two studs on the outlet of the exhaust manifolds.
I've also seen them on the main battery cable stud on the starter/starter solenoid (other makes).
About all I can recall.

Mike

[mapman]

I've also seen them on the carb base mount studs.
Rob

[StudeRich]

The 5/16 National Fine Brass Nuts (1/2" Wrench) go on the 4 Carb. Studs. Also 3/8" Fine Brass on 6 Cylinder Manifold to Block.
I know of no other "Hot Spots" where they are required.
I cannot think of ANY use for 7/16" unless someone wanted no rust on Bumper Bracket Nuts.

[jclary]

I have used them after struggling to get steel nuts that have nearly rust welded to the studs off. Never gave much thought to whether it was originally correct. Here in my part of the humid south, rust welding on rarely disturbed fasteners is always a concern. One thing I have learned is to make sure as much as possible that the mating surfaces are clean and squared up. Unlike the steel nuts, the brass cannot take over tightening to make up for poorly prepared mating surfaces if you are attempting to squeeze gaskets a little harder to make up the difference. Cutting a stripped brass nut off a stud in a hard to reach space is no picknick.

[(S)]

The old /new 8's had brass nuts at the carb studs and at the exhaust flanges/ to pipes. The 6's also used brass on the carbs and intake/exhaust Manifold studs, exh stud to pipes. Don't count out the oldies, they were used way way back also.

[drrotor]

I have used them after struggling to get steel nuts that have nearly rust welded to the studs off. Never gave much thought to whether it was originally correct. Here in my part of the humid south, rust welding on rarely disturbed fasteners is always a concern. One thing I have learned is to make sure as much as possible that the mating surfaces are clean and squared up. Unlike the steel nuts, the brass cannot take over tightening to make up for poorly prepared mating surfaces if you are attempting to squeeze gaskets a little harder to make up the difference. Cutting a stripped brass nut off a stud in a hard to reach space is no picknick.

You might find it helpful in your humid climate to assemble things with brush-on Anti-Sieze applied to the threads. Also a good idea on all spark plug threads, or other applications where you want to be able to disassemble without headaches! I made a habit of using it in my Auto Repair shop after various customers had to have cylinder heads replaced from seized spark plugs...

[Mark L]

I recently fixed an exhaust leak on my Lark, where the left exhaust manifold connects to the head pipe. The brass nuts were partially stripped, and the steel studs were rusted and partially stripped as well. I installed new steel studs in the manifold and new stainless steel nuts with some nickel-based anti-sieze for good measure. I shouldn't have to worry about getting the nuts off the studs the next time.

[bsrosell]

THANK YOU!! Stumbled on this, and never knew the exhaust nuts were SUPPOSED to be brass. Just ordered a set on Amazon for $5 if anyone needs some (another thread discussed they are hard to find….). Perhaps that is why my exhaust manifold studs broke off when I was removing them several years ago….
For the 100th time, what would we do without this forum?