Painting an aluminum intake manifold?

[Magnumcharger]

I've got an Edlebrock aluminum four-barrel intake manifold that I'd like to paint engine color.
I'm thinking that maybe it should have a primer coat of some kind put on it prior to the actual color coat.

Maybe cadmium plating?
Or a zinc-chromate primer? If so, does it come in aerosol spray cans?

[Ghoste]

I just shot mine with some rattle can engine paint.  It's been fine so far going on a few years now, so...

[NMike]

best if you totally degrease it, then bead bast it. the paint will love to stick to that.

[Magnumcharger]

I bead blasted it the other day, which was a good thing to do, as I discovered a huge crack running from one port right through the entire thickness of the piece, to the middle. This might explain why I got the manifold for free.

Fortunately, I look for cracks for a living, and I could easily isolate the extent of the damage.

I have a friend with a TIG welder, and it was fixed very quickly. He also suggested I heat the manifold in my oven - up to around 200 degrees - just prior to painting it.
He said it would help flow the paint out, and possibly even make it stronger and less resistant to damage.

I'll give it a try.

[daytonalo]

Zinc- Chromate, use it on bare alum . It has been what we use on all Alum in marine Industry . Buy it at any boat store like West marine . Use it and top coat will never lift

[BigBlockSam]

i glass beaded mine,  then painted it with a rattle can siver paint. it looked great but after a while heat from the exhaust cross over turned it brown . now    i use a valley  pan that blocks the exhaust cross over . so the paint stays nice. Rene

[bill440rt]

I've used Plasti-Kote's High-Heat Engine Primer in the past with great results.
I run an Eddy Performer intake on my '68, which gets driven regularly during show seasons. It's painted with MP turquoise engine paint also. It still looks great after many years.

[Magnumcharger]

Aye.

[Chatt69chgr]

Zinc Chromate (it's a flatish yellow color) is the preferred primer for aluminum.  As stated, you can buy it in spray cans.  Obviously, the surface needs to be chemically clean.  Glass beading and then washing with laquer thinner will accomplish this.  Or if the piece is clean, then just use the laquer thinner to remove surface oils.  Best to have piece at something like 70 degrees or so before applying.  Warming up the part for finish paint coat to get it to flow sounds like a good idea.  Not too hot though.  I would think 200 degrees would be too hot.  More like 100 degrees.  After it drys, put it in the oven and bake on the paint at 200 or so degrees for 1/2 hour.  Make sure wife is not home before doing this.

[bill440rt]

Zinc Chromate (it's a flatish yellow color) is the preferred primer for aluminum.  As stated, you can buy it in spray cans.  Obviously, the surface needs to be chemically clean.  Glass beading and then washing with laquer thinner will accomplish this.  Or if the piece is clean, then just use the laquer thinner to remove surface oils.  Best to have piece at something like 70 degrees or so before applying.  Warming up the part for finish paint coat to get it to flow sounds like a good idea.  Not too hot though.  I would think 200 degrees would be too hot.  More like 100 degrees.  After it drys, put it in the oven and bake on the paint at 200 or so degrees for 1/2 hour.  Make sure wife is not home before doing this.

I do agree Zinc Chromate primer is good for aluminum, but I just don't know how it will hold up in a high-heat situation.
I assume you are referring to DuPont's Vari-Prime? Unfortunately, paint does not like to adhere directly to this primer. You need to topcoat it with either an epoxy or filler primer first, this is also spelled out in their tech sheets.
I also do not recommend washing parts down with lacquer thinner prior to painting. Lacquer thinner contains chemicals which can actually CAUSE fisheyes. I would use a standard paint prep solvent.

I also do NOT NOT NOT recommend baking freshly painted parts in your home oven, in your kitchen of all places. They will give off chemicals & fumes you do not want in your home. Ever start a freshly painted engine? You know what I'm talking about then.
The paint will bake just fine either left out in the hot sun or by running the engine OUTDOORS.



Everyone has their own preferred methods, whatever works for ya.

[BrianShaughnessy]

Everyone has their own preferred methods, whatever works for ya.

Drop it off at the powdercoaters. 

[Magnumcharger]

Everyone has their own preferred methods, whatever works for ya.

Drop it off at the powdercoaters. 

$$$$$$$$

[Captain D]

I'm glad that this topic came up...I was wondering the same thing.

I've got an Edlebrock Intake as well. It's solid, just needs to be cleaned up. I went into Advance Auto & they suggested using something called "Purple-Power." It's a degreaser and all around a quality cleaner.

To be honest, I didn't think the aluminum intake could be painted. I asked a friend of mine if I'm able to paint it (if it'll hold the paint), and he said no. Well, I'm glad that I came across this thread! I know that I can get high temperature primer + high temperature paint (in aerosol can, up to 1200 degrees) at Advanced Auto. I think they even sell an aluminum color in high temperature paint. Would any of these products work? Has anyone used this combo before? If so, how did it hold up? If anything, I might be able to simply clean it without applying anything to it. But, I was curious to ask about these high temp. paints....

Thank you for any responses,

Aaron

[BrianShaughnessy]

Everyone has their own preferred methods, whatever works for ya.

Drop it off at the powdercoaters. 

$$$$$$$$

That's a bit of exaggeration.     $40-$50 for powdercoating intakes from my local guy.   I paid $75 for ceramic (jet hot) on a 6 pack intake from these guys  http://www.qccoatings.com/     

[41husk]

I painted my aluminum intake with high temp clear over a year ago and have had no problems.

[Magnumcharger]

Working on an Airforce Base has it's advantages...sometimes.
I was discussing this problem with an aircraft structures tech the other day.
His thought was to give the bare metal a coating prior to painting, much in the way that they do on aircraft.
His suggestion was to use Alodine, and specifically, Alodine 1132. So I did.
(And he provided same...)

http://www.aircraftspruce.com/catalog/cspages/touchprep.php

http://en.wikipedia.org/wiki/Passivation

"Aluminum may be protected from oxidation by anodizing and/or allodizing (sometimes called Alodining), or any of an assortment of similar processes. (See terminology, below.) In addition, stacked passivation techniques are often used for protecting aluminum. For example, chromating is often used as a sealant to a previously-anodized surface, to increase resistance to salt-water exposure of aluminum parts by nearly a factor of 2 versus simply relying on anodizing. Aluminum naturally forms an oxide almost immediately that protects it from further oxidation in many environments. Unfortunately, this naturally-occurring oxide provides no protection during exposure to any saltwater spray environments, such as occurs in areas near bodies of saltwater. In such coastal environments, unprotected aluminum will turn white, corrode, and largely vanish over periods of exposure as short as a few years. The only way to prevent this from occurring is to use a more robust conversion coating on aluminum surfaces that will not be affected by the saltwater atmosphere. Alodine, Iridite, and chem film coatings can provide varying amounts of protection for aluminum surfaces."

[bull]

Everyone has their own preferred methods, whatever works for ya.

Drop it off at the powdercoaters. 

I thought about doing that but then wondered, if I'm painting my 383 blue can they match it?

[Charger-Bodie]

Ive painted many engines with DelStar enamel, Ive never primer any aluminum parts and never had any peel.

As long as its clean and you don't use cheap spray bomb paint it will turn out great!

P.S.  I'm not a big fan of powdercoat ! Period  The stuff is thick and just doesn't impress me at all. 

[charger50071]

I don't think the factory ever primed any engine parts. I've always cleaned and degreased my engines and just painted them with Dupont Centari.