I'm planning on replacing both right and left front fenders with aftermarket ones for my 1983 F-150 and I was wondering considering that since the aftermarket fenders will be new could a person use POR-15 over a surface that was before primed with epoxy primer? I realize that POR-15 is most efficient and was developed to be used on rusty surfaces,but I thought the added protection of POR-15 painted over epoxy primer especially on the inside of the inner fenders would act as a double sealant against moisture and other corrosives especially salt? I would scuff the primer with 220 grit sandpaper so the POR-15 would have an anchor to attach to and then use POR-15? Is this one method that could be recommended? Has anyone tried this before and have had satisfactory results? Any input would be appricated! Thanks!

 

they make a tie coat for POR that you are suppsed to put down before the POR. POR is very specific on following thier instructions, I've heard horror stores from people that strayed away.

 

If it were me I would simply put on two good coats of epoxy primer which is what I did on my 65. Since the truck also had body color on the inside it also got two coats of hunter green.

If you sprayed on two good medium coats of epoxy primer then you have no worries about moisture penetration unless your spray technique is bad.