c3 69 Manifold cleaning and dressing

[John A.]

Hi all,

I'm in the process of freshen up the appearance of my BB. Would like to know what is a good method for cleaning up exhaust/intake manifolds and are there any tricks used to keep the exhaust manifolds from rusting again?

Thanks!

[Jack H.]

Re: c3 69 Manifold cleaning and dressing

Clean-up: Remove and lightly media blast for best appearance or leave installed and slather/brush with a form of rust remover (e.g. Naval Gel) for a 'reasonable' appearance.

Rust Prevention: You're on the horns of a dilema here. Exhaust manifolds were either left natural or painted with the engine (varies from year to year along with engine). If you paint Chevy orange, the exhaust heat will rather quickly burn off the paint and you're back to square one in terms of rust.

If you protect the manifold with a form of coating (flame spray with say SS material, or paint with cast iron 'appearing' coating--some are better than others), best bet judges will detect the deviation from factory original appearance and extract a 20% originality deduction for violation of the FINISH axis of factory concours originality.

Bottom line, if you want full scoring points under factory concours inspection then leave 'em as the factory did. If you want a good looking engine compartment for a driver, then apply one of the high temp resisitive coatings as mentioned and prepare yourself for scoring loss on the judging field....

[John H.]

Re: c3 69 Manifold cleaning and dressing

I don't like mine rusty-looking, only costs a max of three points in judging; your call on how you like yours

[John A.]

Re: c3 69 Manifold cleaning and dressing

Any tips for the intake manifold?

[David H.]

Re: c3 69 Manifold cleaning and dressing

I media blasted my manifolds, then put some Dri-Slide on a rag and wiped them down. The graphite goes into the pores, helps prevent rust, and won't "melt".

The color of the manifold is not much different than a freshly media blasted manifold, but a judge would surely notice. The graphite goes into the pores of the metal, so it doesn't look thick or coated. You can touchup, as well, just using the rag. There was a write up in the Restorer magazine, some months back, about a similar approach.