rawky

Just cleaned the intake manifold today , and some paint flaked off it as I scrubbed it... It is supposed to be painted?

cold_beer839

If you have original coatings, you must clean them like a baby's butt, very gently.

Mrmerlin

what flaked off isnt paint its a powder coating. to do it right will require removal of the intake and a complete stripping (media blasting) of the intake then a wash and bake, to out gas the metal then a new application of powder coat.
Others have tried painting and that also seems to work OK but you should test the paint to see if fuel or other solvents will remove it. If you were going to use paint then i would suggest some kind of epoxy paint

mj1pate

Bead blasting barely touched the coating on my original intakes. I had to have them sand blasted, with a cutting media. I used commercial, high temperature engine spray paint on the intakes and it worked fine. Paint is a little vulnerable to chipping when you slip while using a screw driver and scrape the paint. But with care, paint works fairly well.

rawky

But I've used an abrasive cream, and the inatake has come out a beigey colour, not the bright silver shine I'm used to....Why?

edit: Think I wasnt to use it on the intake , But it looks fine, doesn't bother me in the slightest...

RKD in OKC

The intake on my 90 GT was chunking off big time and the inside was all caked up with gook. Had it sand blasted inside and out for $75. Then had it powder coated silver chrome for $80. This was several years ago. I did the lettering with Testors Enamel.



Sold the car before I got around to doing the cam covers.

cobalt

It is not powder coated it is painted and it is done in Zermatt Silver.

It is also magnesium and if you expect the job to last you will need to grit blast it with a slag product like Black Beauty and then use a dichromate pickle to prepare the surface for paint. Otherwise it will not last as long as you would like.

The_Remora

I get nervous about having one of these things bead blasted after seeing what Tass went through with his race car intake...

cobalt

Magnesium is a relatively durable material assuming it is not allowed to be impacted by the elements directly. That is why a good coating is critical. Coal slag is a good medium to use since it disintegrates on impact although it does remove a few thousandths of material. Unless the casting suffers from corrosion or microshrinkage you should be fine.

pcar928fan

Yea, I always think about what Sterling went through due to this same thing! TERRIBLE! Of course it led to a decade long odyssey of building the monster motor he now has! So I guess that is the bright side...it pushed the envelope on 928 development! Thanks G-man!

rawky

Turns out that if I want it silver again, it will have to be blasted and coated again...

WallyP

I was in a hurry to get to SITM...

The finish on my 90 GT intake and cam covers was flaking badly. I had to pull the intake anyway, but didn't have the two weeks for bead blasting and powder coating. The finish scraped off very quickly and easily, leaving the gray factory coating undamaged. A quick scrub with abrasive pads and solvent, three cans of silver wheel paint, and the intake and cam covers looked pretty good. The intake was off the car, the cam covers were finished in place.

cobalt

The Gray coating is the result of the acid pickle or dichromate treatment. It can vary from a gray to goldish color depending on hardness of the casting and exposure to atmosphere. If it is powdery be careful it can be explosive if you try to use any grinding tools on it in this condition. Also corrosion on magnesium can be observed under black light.

sty3x

Has anyone painted or powdercoated their intake same color as factory??

cobalt

You might be able to get something close but the actual color is Zermatt silver which I don't think you will find in a powder coating. It also changed color over time from heat.