300Tdi manifold studs and nuts - can they be lubricated to prevent rusting?

[86mud]

Hi All

I am in the process of replacing the intake/exhaust manifold on my 300Tdi. I notices that the nuts had some minor surface rust.

While I am waiting for the dishwasher to finish its cycle (the intake manifold is in there [biggrin]) I am wondering how I can prevent the nuts and the tips of the studs from rusting.

Any ideas?

Oh and here is a picture of the head all cleaned up. It was a bit of mess



Thanks

[loanrangie]

I wouldn't worry about them, they heat up and therefor rust. Use some copper anti-seize is about all you can do.

[AK83]

copper nuts?
I read that to help removal in the years ahead(eg. if a gasket fails or something) copper nuts can help a lot.

[simmo]

Recommend you don't use anything lower quality than grade 8 nuts, and put copper slip or nickel antisieze on them, stops them from binding up and provides some corrosion protection to the exposed threads.


You'll never have a problem getting them off if you use nickel based antisieze, its widely used in industry on big engines and turbines for high temp threads etc.

Just be aware to reduce the torque by 1/3 when you use the anti sieze, ie you use 66 % of the torque for a normally oil lubed bolt , other wise you can over stress the stud.

I don't think copper /brass/bronze will be strong enough at elevated temperatures and will be a head ache for you.

cheers simmo

[86mud]

Thanks guys.

I just wire brushed the studs, cleaned everything else up, then put it all back together.

It seemed to drive a little better as well. Maybe cleaning the oil residue from the inlet manifold and pipes plus the intercooler as well as the new manifold gasket made a difference

Cheers