The Stovebolt Site Forums The Shop Area Paint and Body Shop To prime or not to prime

I've ordered the correct Chevy blue for my '59 engine - the high temp stuff from Eastwood. (yeah, it's a little pricey but they make good stuff.)
I've media blasted things like the valve cover, oil filter, water pump, etc., which leaves them with a somewhat rough surface, about the equivalent of what 60 grit would produce. So the question: should I prime those before applying the blue?
Priming will provide a smoother base for the blue, but will the heat transmitted from the engine cause bubbling in the primer? Or do those peripherals not get hot enough for that to happen? (Assuming I use a regular rattle can primer.)
Or, will that Eastwood paint go on thick enough that the rougher metal of those pieces won't make a difference even without a primer?

Thoughts?

the "correct" color for a 59 truck engine is gray, blue is for a car engine .... if you want to use a primer use a high heat type, but no telling what primer will be compatible with Eastwood paint

Bill

If you want to prime it, they also have high-temp primer.

A clean surface is key, and I recently primed the parts you mentioned with high-temp primer before painting- I think it was VHT brand primer.

Before that, my uncle had painted my engine & parts back in the early 1990's with just Chevy blue engine enamel. He didn't use any primer at all, and it took me some time to bead blast it all off. It stuck on there very well, and his rattle-paint was nothing as well-reputed as the Eastwood brand.

What does the can/instructions say about priming? Whatever that says is what I would do.

Brad

I blast a good many parts in my bead blaster and take them "most" of them out and shoot the paint on them. Never had a problem yet.
If your sand is new or your using a coarse sand or aggressive type media it will probably need some filler primer or extra coat of paint....as most folks say "it just depends'

If you want a real smooth finish on the blasted tin parts (next time use a finer media), 1. don't worry about the water pump or anything else cast. 2. two coats of high temp primer 15 min apart, let dry well and wet sand with 400 grit. Clean everything off and another coat of primer if you have sanded down to metal, otherwise 1 even coat of paint.

I never use primer on media blasted parts. The media blasting provides an excellent "tooth" for the paint to stick well. Been doing this for years and never have a rust or adhesion issue. The only word of caution is high temp paint(rust tends to come through the high temp unless you lay it on thick...so a high temp primer might be prudent).