Painting exhaust manifolds

I'm considering high temp paint for my cast iron manifolds and was thinking that a pre-heat in an oven would help with the paint bonding. Has anyone done this proceedure and did it help with the paint durability?? What temp did you use on the oven?? I'm going to glass bead the manifolds first to clean them up.

 

I would consider not preheating as it may affect the way the paint reacts when it hits the manifold.

 

I have never seen a so called High Temp Paint last very long on exhaust manifolds, BUT,,, I have seen very good results from this place,,, http://www.jet-hot.com/

Hope this helps

 

POR-15 has a manifold paint that's supposed to look like cast iron. They call for sandblasting first IIRC.

I have baked some things in my oven, and most paints do not react well to too much heat. If you bake too hot, the paint will crackle or wrinkle, and I expect it will be nearly impossible to get paint to stick to a heated object. The reducer will flash over and you'll have no time for the paint molecules to bind to the surface. You can give a little heat (ca 200F) to speed drying after application though - this works particularly well with the Rustoleum enamel, which usually takes forever to dry anyway.

 

I painted mine with engine paint, Ford Blue I think, and it seems to hold pretty well


Bob

 

It's called factory manifold grey. I used it on Pete. Excellent paint, as all POR paints are, and has a bare metal look. Only about 5 miles and some idle time on it so far so I can't speak to the durability. However, it's been at operating temp several times for 10 minutes or so and has shown no hint of any changes yet. Only pic I have at work is from a distance.:v6:
View attachment 18819

 

Thanks guys, I ordered the POR product. Should be here next week.

 

Were you satisfied with the finish on cast parts????

 

One of the secrets to getting paint to stick to manifolds is heat cycling. After installing them, run the engine a few seconds to get the heat up in the manifold, then let them cool completely. Run the engine again for a couple minutes followed by a cool down. Do this two or three times getting the manifolds hotter each time before getting the iron really hot (i.e. driving) and the paint will last longer.

 

I made up a set of headers out of plumbing pipe and sandblasted them before painting them with POR-15. Like NorCoJeeper says, the key is to build up the paint in layers through several heat cycles. Mine seems to stick real well even though I've heat wrapped the pipes and gotten them wet several times. Just watch out for hot anti-freeze! I spilled some on mine and it ate right through the paint like nothing I've ever seen. Had to start over with the paint as it started rusting almost instantly.

 

This is great info guys, I'll remember this next week when it's time to install.

 

I did Jet Hot a decade ago... to this day I have no rust!! Worth every dime!