questions for painting lower end

[learning to fly]

Hello, I have a 99 mercury 15hp that has some corrosion on the leg. It was on a dinghy and some crap had grown on it. I have sanded it down to bare metal and want to know the best way to paint it. I am not looking for a profesional job, just protection from the elements. I was going to use the mercury black paint for outboards but just wondering if i should prime it beforehand orwhat. Any info would be great
thanks

[Mollers]

Originally Posted by learning to fly

Hello, I have a 99 mercury 15hp that has some corrosion on the leg. It was on a dinghy and some crap had grown on it. I have sanded it down to bare metal and want to know the best way to paint it. I am not looking for a profesional job, just protection from the elements. I was going to use the mercury black paint for outboards but just wondering if i should prime it beforehand orwhat. Any info would be great
thanks

Clean it off with thinners and give it a couple of coats of acid etch primer. Follow instructions, a lung full is none too beneficial.

[doggypaddle]

And when you are ready to paint it sand it down immediately before painting. Aluminium corrodes extremely quickly believe it or not, the oxide layer which forms rapidly prevents futher corrosion, AFAIK its better to get the etch primer onto freshly keyed aluminium.
I always use fairly coarse paper ~~100 grit then prime it, then use several coats of ordinary primer/undercoat which you can flat back with a finer paper ~400 before putting on the top coat. that wayyou get the best chemical bond and mechanical bond.