Engine painting

Hi all,
I'm about to reprint intake manifold on a Chevy 350.
Have stripped removed all old paint and degreased and is nice and clean.
Going to spray with engine enamel.
My question is do I need to spray on a coat of primer first or go straight on with finishing color ?
Thanks,
Mike

 

Either way, but the answer is no, you can spray topcoat directly on the manifold, though I usually use a zinc chromate primer to help with corrosion. Now that you have it clean, you should take some time and remove casting flash and other imperfections in the manifold. Most have quite a bit of junk and casting marks, which can be removed easily, if tediously, producing a much better result.

 

You should primer the manifold for the best finish coat adhesion.

If you can, stick that manifold in an oven for an hour or so at 200 degrees fahrenheit or so. Warning....don't do this if you're married and try not to do it inside a house. It's smelly.

 

Sure, you can bake your manifold in the house, with your better half's oven, though prepare yourself. I have a really nice 50 amp oven in the shop, I often use to post cure parts, having had to replace the one in her kitchen (a place I've been justifiably banned from for years now), all because I was trying to lower the moisture content in a hunk of live oak (ever smell wet oak cooking?). I have gathered lots of tools like this, a blender, a vegetable chopper, a refrigerator, a toaster oven, electric carving knife, etc. This is the cheap way to upgrade your shop equipment, so marry a well equipped woman and save some bucks. When baking hi temperature paints, I like to be closer to 300 degrees.