My lower unit on my Mercury outboard has that white oxidation look going on and I want to freshen it up.  I've read that you should use Mercury paint but others have used Rust Oleum, so if you have re-painted yours any advice would be appreciated. 

Thanks, 

I have painted three Mercury lower units on my boats over the years. I have always used the Mercury phantom black paint. It is easy to apply and holds up awesome. Well worth the 12 bucks a can. Make sure you take your time and scuff up the whole lower unit with a scotch brite pad and wipe it down with acetone. A paint job is only as good as the prep work that goes into it. 

Toilet bowl cleaner does wonders on removing deposits left by water.

36 minutes ago, slonezp said:

Toilet bowl cleaner does wonders on removing deposits left by water.

Like what kind of cleaner?  Lime away?

Undiluted vinegar works well too

going out to try that now, so I won't stink by the time we go to bed

37 minutes ago, warrior1 said:

Like what kind of cleaner?  Lime away?

Pick up a $2 bottle of any gel type of TB cleaner and a pair of rubber gloves. Put it on with a sponge or green scotchbrite pad. Let it sit for a minute or so but don't let it dry. Rinse. The TB cleaner will burn your skin so don't say I didn't warn you about wearing gloves.

after taking a closer look, some of it came off pretty easy with a 0000 steel wool and after hitting it with polish and then wax looks great. in other areas, it looks like the clear coat is bad, so it may need to be painted.