non rusting bolt into cast iron ?

[steveo3002]

ive got a bolt on heat sheild on my cars cast iron exhaust manifold , they often sieze up and snap causing hassle

copper slip seems to vanish

what can i use ? guessing stainless isnt ideal ?

 

[PhillipM]

Brass

 

[The_Yellow_Ardvark]

Brass or lots of copper slip.

 

[Ross365]

Has anyone ever used milk of magnesia on threads to prevent seizure? I remember the technicians who looked after high temperature autoclaves used to do it at a firm I worked for many years ago. They just applied it to the threads with a paint brush. Brass sounds much better where there's no great stress.

 

[Bullet2012]

Silicon bronze.

 

[zx9]

A steel stud into the manifold with the heat shield retained by a brass nut.

 

[bricol]

Proper high temp anti-seize - I've got some American stuff (name escapes me at the moment) that hasn't failed me yet, but I would imagine any decent brand name would work.

 

[graffian]

I think Loctite N7000 is OK at elevated temps.

 

[tom2207]

molly disulphide is what im using at the moment bought as a lube for bmw driveshafts but i use it on brass header nuts and the combination seems to work well , and as some may know bmw headers glow in the dark after a good run , or mine do .

 

[Screwdriver]

A steel stud into the manifold with the heat shield retained by a brass nut.

I believe this is the standard for replacing exhaust flanges. That's what I do on my bikes.

 

[Cobbler]

I’ve bought some ceramic equivalent to Copaslip from Toolstation, it’s supposed to go to far higher temperatures but I’m yet to try it. For exhausts, there used to be some steel nuts with stainless inserts in, I think they were standard on Jaguars at one time.