Painting intake manifold (questions)

I'm going to replace my exhaust manifold and decided to use VHT flameproof paint on the exhaust mainly as a rust protectant. Then I figured why I have it all apart why not paint the intake manifold that I can actually see.

I was planning on using the same VHT flameproof paint. I know it doesn't need that high of a temp rated paint but it shouldn't hurt either? I was planning to bake both manifolds in a dedicated powder coat oven to make sure it cures.

Will I have any problems baking the intake manifold though at really high temps? Obviously I will strip it down and prep but I was worried about anything warping or not able to handle the high bake temperatures.

Or, should I scrap the flameproof paint and go with their engine paint instead? I was worried with the intake right next to the exhaust it might get too hot for engine paint.

DON'T take the intake manifold past 350 degrees or so. Hopefully some metallurgy experts will chime in, but past a certain temperature cast aluminum changes it's crystalline structure and basically becomes very brittle.

With the exhaust manifold, obviously, have at it.

DanMan2k06 said:

DON'T take the intake manifold past 350 degrees or so. Hopefully some metallurgy experts will chime in, but past a certain temperature cast aluminum changes it's crystalline structure and basically becomes very brittle.

With the exhaust manifold, obviously, have at it.

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Thanks for that bit of information, pretty much solves the issue then. The VHT engine paint only needs 200* to cure so I'm going to use that instead. I'm still having a hard time deciding to cure the paint on the jeep or in an oven. I want it to last and be durable but only needing 200 degrees I might just cure the intake on the jeep. I have to imagine it will get to 200 degrees sitting next to the exhaust.

Sounds like a plan... make sure you keep the paint off the gasket surfaces (block to manifold gasket, throttle body, etc) and might want to keep the power steering pump mount location clear as well. Not really sure.

Also, sand/soda blasting or even a good scrub with brakleen, degreaser, then vinegar should take off the surface corrosion and engine grime.

kastein said:

Sounds like a plan... make sure you keep the paint off the gasket surfaces (block to manifold gasket, throttle body, etc) and might want to keep the power steering pump mount location clear as well. Not really sure.

Also, sand/soda blasting or even a good scrub with brakleen, degreaser, then vinegar should take off the surface corrosion and engine grime.

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I was planning on masking any contact areas for sure, don't want to mess up a gasket surface. Also I was going to use in order: degreaser, brake cleaner with metal brush then some paint prep stuff I forget the name but it's a real harsh chemical ha.

Hopefully all will go well and I'll get some pics up. Still waiting on parts so won't be doing anything this holiday weekend sadly.

iwannadie said:

The VHT engine paint only needs 200* to cure so I'm going to use that instead. I'm still having a hard time deciding to cure the paint on the jeep or in an oven. .

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I wait until the wife is gone for the day and bake paint in the oven, set at at between 175-200 degrees. She hasn't caught on yet in over 30 years.
Now, don't tell her!

works great for paint, not so good for preheating bearings and gearsets though takes a lot to get rid of that smell.

from what I hear anyways, I'm a bachelor and can heat gearsets in my oven all day and no one cares

lazyxj said:

I wait until the wife is gone for the day and bake paint in the oven, set at at between 175-200 degrees. She hasn't caught on yet in over 30 years.
Now, don't tell her!

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I am more worried about long term health effects of the fumes/chemicals that are trapped in the oven later when there is food in there... Call me paranoid I guess ha.

iwannadie said:

I am more worried about long term health effects of the fumes/chemicals that are trapped in the oven later when there is food in there... Call me paranoid I guess ha.

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After baking, I set the oven into it's high-temperature self-cleaning mode.
Seems to get rid of the smell and the oven is clean afterwards.

lazyxj said:

After baking, I set the oven into it's high-temperature self-cleaning mode.
Seems to get rid of the smell and the oven is clean afterwards.

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Yea I am tempted. Someone at work brought up a valid point about using oven cleaner. That stuff is a pretty nasty and smelling chemical and you can cook after using it just fine.

I found someone local with a dedicated powder coating oven who is willing to bake the stuff for me so it's no biggie really.

iwannadie said:

Yea I am tempted. Someone at work brought up a valid point about using oven cleaner. That stuff is a pretty nasty and smelling chemical and you can cook after using it just fine.

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Ideally, if I had the room, I would pickup an old oven and use it only for garage projects and not have to worry about the wife or any health issues.

Well, I got the exhaust manifold painted today. I couldn't find anyone with the VHT engine metallic paint I wanted in Red. The only place that sells it local has it in grey, gold and burnt copper. The burt copper actually looks very tempting and I might just go with it. Although I'm starting to chicken out on painting the intake...

I'm also nervous how my exhaust is going to turn out and last. I read a ton online and people seem to have 50/50 results. Some swear it lasts for 10 years other say it burns off in 10 minutes lol. I prepped it the best I possible could, laid down 3 light layers of flameproof primer then hit it with 3 light layers of top coat. It looks great now although the orange I used is seriously Blaze orange, oh well can't really see the exhaust anyways.

Pics to come of the exhaust.

Ok here's some pics. The flash really screws with the color, the light spots I really don't see outside of the picture. I was trying to go with as light of coats as possible just to get the color to show.

I powdercoated my intake with near chrome and finished with a clearcoat.

iwannadie said:

...I couldn't find anyone with the VHT engine metallic paint I wanted in Red.Although I'm starting to chicken out on painting the intake....

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painting the intake shouldn't scare you-- it will hold up fine to the exhaust heat with anything you spray. I've used all types of paints on them and never had problems with it burning off or discoloring from heat. Obviously, it may not hold up as well to chemicals as a dedicated engine enamel will, but you can get some nice metallic hues in standard auto body paints.

I "threw together" a "four squirrel screamer" with the plans to sell it for a quick buck (ended up keeping her for a DD) and am very impressed with how well the paint has help up.

This was during cylinder head replacement (fresh paint), but I can assure you the paint hasn't flaked/discolored/burned off in the 3000 miles it's seen. I'll be the first to admit that it probably won't hold up to harsh chemical cleaners, but it shouldn't need too much cleanup (since when I build a motor, it never leaks) before the next rebuild at 300,000 miles......

Well, I ended up chickening out on the intake for now at least. Once I had it all apart and I started to clean the intake I wasn't getting much of the grim off. I didn't want to attempt to paint it unless it was 100% stripped down to metal. I didn't have the time to get it tanked or blasted so it will have to wait. Shorty, I've seen that picture before on here and honestly was part of what inspired me to paint my intake .

I am a bit disappointed in the flameproof durability. I was as careful as possible on assemble and still managed to scratch it and touch it with oily hands. The slightest touch against the intake manifold managed to scratch off the top coat and some times the primer even. 8 layers of baked on paint and it sure is delicate. The flat paint really likes to absorb any oil/grease and doesn't come back off also. Maybe the clear coat would help with this, next time I guess.

The paint held up fine when driving so far, no sign of problems as far as that goes at least. No smoke or smell coming from the paint like I've read other people have problems with. No blistering or bubbles yet and I drove it pretty hard to stress it.

I guess I should have masked it off for the install though oh well, it was just a for fun/rust prevention project anyways not a show piece. When I do the intake since it's much more visible I will have to mask it off for install and clear it also.