Anti seize on exhaust - yes or no?

[Mikeymo]

Well, what is says really. Would you use anti seize on exhaust flange bolts, turbo bolts, exhaust manifold bolts or will it just bake on?

[Oilydad]

Personally I wouldn't bother.

If all the joints are clean, done up properly, and in good condition, the chances of you having to disturb them again before the components wear out are quite slim.

[Mikeymo]

Thanks. Except the exhaust system itself is stainless steel, hopefully to last a lot longer than mild steel.

It doesn't seem to me like a lot of bother, just wondering if there's a downside.

[stevo48]

You would have to use an extremely high temperature resistant substance, industrial high temp grease?? even then I don't think it would last as the exhaust is open to the elements as well as extreme heat.

[Oilydad]

If you're worried about bolts etc coming loose then assemble with loctite or something like that. You can't really use any lock- bolts with plastic inserts because they will melt away in no time.

But this might interest you if you really do want to do it. Works on the basis of wedges within the fasteners. The military use them for obvious reasons......but I'll bet they are pricey!!

http://www.longloklocking.com/pdf/handbook.pdf

Like I said originally. For me.....no.

[Mikeymo]

Thanks. I didn't really mean anti seize to stop the bolts shaking loose. I'm more concerned about being able to disassemble the thing later.

[arcturus]

For a stainless exhaust you should stainless bolts clamps etc. You will get an electrolytic reaction where stainless contacts mild steel.

[Hinckley]

Alumslip(by Molyslip) or Never.seize(by Bostik) are the two I use for exhaust systems and turbochargers, Alumslip is a Aluminium high temp version of Copaslip, Never.seize is similar but has Nickel added for extra temperature resistance.

I have not had any problems in dismantling exhaust or turbocharger nuts lubricated with these products - even after 100k miles.

[PAW1212]

In descending order of choice, I would go for:-
Graphite (dry, greaseless) lock lubricant or a soft pencil might do.
Copper-Grease (easy to get hold of) basically brake lubricant
Aluminium-Grease (not so easy to find) brake lubricant again
Aerospace "thread-lock" compounds (expensive)

Personally, I prefer to fit soft metal nuts instead (copper, brass, aluminium, etc) of steel, at least if they do corrode you can break them off fairly easily without damaging the studs. I suppose if you really wanted to, you could fit titanium or inconel nuts!

If you hve a 3-wire O2 sensor, you may get some galvanic corrosion anyway, as the exhaust provides the ground for the sensor. A 4-wire has a seperate earth cable, so would be less susceptible.

[Clan]

you dont need anything as long as you use the correct bolts and studs, you will always be able to undo the turbo bolts they are titanium and have a hard helicoil type insert , top quality £4 each! they go right back to the 940 and still current .. you can bet some unsupsecting person has replaced them with ordinary mild steel nuts somewhere down the line if its not original ..