I picked up a set of slightly used headers, used enough though that the painted finish burned off and they ae now rusted, not rusty but have a rusted finish. I intend to use them on a junkyard build and was wondering if anyone had any luck recoating them. I considered having them blasted and ceramic coated but that negates their advantage of being cheap. I considered using VHT since I have had reasonable luck with that on manifolds. What have you had success with?

Thanks in advance, Kevin

I have had good results with bbq grill paint.

have them blasted and VHT in the color of your choice

That was my original plan but was wondering if there was more info out there. Fortunately I can blast myself so that helps the cheap factor.

The Headers on my Factory V8 Jeep CJ 5 were cheap Headman Headers. They rusted over several years. Needed to pull them off for a valve-job. Since they were off, I gasket matched the tube ports, degreased, and removed remaining paint, then, what to do about the rust.....?

I tried several methods, blasting, abrasive disks and a die grinder. Worked for flat surfaces, not so great on the tubes. I went a tiny bit radical. I found a large'ish rectangular plastic tub, filled it with Swimming Pool (hydrochloric) Acid (wearing gloves and safety goggles, etc, and dipped the headers into the acid. The rust instantly disappeared. I washed the headers with baking soda and water, rinsed. They flash rust very lightly, but very quickly as they air dry, so I had to dry with compressed air, but that flash rust was not harmful.

After fully dry, I used 2,000 degree high heat gray primer followed by 2,000 degree high heat Silver paint and it has held up for nearly 10-years so far. VHT and RustOleum make 2,000 degree paint products. I think the Primer really, really helps the longevity. I now paint all clean, bare metal exhaust pipes, blasted cast iron exhaust manifolds, etc, with the 2,000 degree primer and paint products.

The 1,200 degree Barbecue-Type Paints (without using high temp primer) all seem to fall short and eventually blister and flake off over time, even when you do your best to remove all grease and rust prior to application.

I found the trick is to metal prep them after blasting, then paint. Best set I ever did, they were good for 5 years and still going.
Doug

Great input guys.

DC how much is the hydrochloric acid?

It's not particularly expensive ($7.29/gal at Lowes) and available at supermarkets, hardware and home-improvement centers as well as pool supply stores. It is also sold as Muriatic Acid.

Keep in mind, it is acid so you need to take safety precautions and be sure to neutralize everything and wash thoroughly. It can damage concrete.

Thanks for the info.

I did a set of used headers with VHT products, they rusted back through in a hurry. If you're not going to blast and/or prep proper, don't bother.

On my Jeep engine Ive seen the headers Glow red from heat (distributor excessively advanced and carburetor lean), yet the paint held up fine. I would not have believed it.

A long time ago, I had some headers blasted, then painted them with rattle-can header paint. They looked nice for about a month, then went back to looking like ancient headers. They are still on the car and working fine, they just look ancient. I like it that way because it's an old car.

Try Q C Coatings in Michigan. They just coated a set for me and they have done headers for friends and they're real nice.

Prep them the same way you would prep a bare car body for paint - 100% clean including the welds. Stove or bbq paint works as well as the specific ceramic header paints. Warming them up with a propane torch before paint seems to help the paint bite better.

If you drive in the rain a lot they will eventually grow surface rust in the collector area.

Tech line coatings inc Do a search, great products.

I use Por-15 Black Velvet paint, does not burn off. Can brush it on, looks good.

Interesting.

Why would anyone go to the double of doing it without blasting?

Hope Springs Eternal... Blasting, Degreasing, Rust Removal are a fair amount of effort and if you could get away with simply shooting some rattle can on 'em, and it it would stick, look better and stop the Rust, I wouldn't blast, etc...

But unfortunately, lasting results that don't flake off and which stops or slows rust, involves cleaning as best you can to Bare metal prior to coating or painting, though it would be nice if you could get away without all that effort.