hose down rusty headers

[RWebb]

not on my 911 - on my VW Vanagon

it has rusty exhaust "headers" on it -- I'm wondering if there is anything I can just spray or paint on WITHOUT taking them off the motor.

Ideas?

[COL 911]

I've used something around the house called Right Stuff 'rust inhibitor'. MFR. is Sunbelt Chemicals in Florida. The label claims to seal the surface via chemical reaction/bonding in preparation for paint. I've used it on exterior metal for years now, and it does seem to retard rust once it's started.

It is effective on surface rust, it seems to penetrate and leaves a semi-gloss surface finish, which takes paint well. I recently used it on my rear sway bar brackets, which looked to have been replaced by the PO. They were never painted, and were rusting all over. I liberally applied this stuff, and spray painted when dry. I know it's protected from oxidation better than it was before.

I never tried it on high heat applications like you're looking at though, but it may prep the old pipes better than regular wire brush/primer before the application of hi-temp paint. Sorry, I can't remember where I bought it...Google might be able to help find it.