Can you do this or should I get all the old paint off? I'm pulling the motor/trans probably this weekend to start the little bit of body work I need to do in the engine compartment and then I am going to paint it. Just the engine compartment for now. Right now I have POR15 on top of the factory paint. If I paint on top of this is that too much? I want this to look very good when I am done.

 

POR-15 should be covered if the area sees any kind of sunlight, else it'll eventually fade and discolor. My rollbar faded after a few years and it had 2 or 3 coats of Por-15 black gloss. They make Chassis Coat that works pretty well. I painted that over my factory paint in the engine bay. Came out well except for the places I got sloppy and had a few runs.

 

The black paint you see in my sig pic is the POR15. I am painting the engine comparment with actuall car paint now. I am doing a metallic blue. I just need to know if I need to get all the old POR15 off.

 

Pretty sure they give directions on the PorShop website for painting over the top of it. If it's clean enough and isn't chipping or peeling I wouldn't think there would be any problems.

 

PRIMING OVER POR-15:
Use POR-15 Tie-Coat Primer after POR-15 is dry, following directions on can. Tie-Coat Primer may be sprayed or brushed in multiple coats if desired. Sands to a perfect finish.

http://marine-paint.com/por-15-faq.htm#primover

 

Cool, thank you. I dont know if I'm going to buy their primer, but this might save me a lot of sanding.