Aluminum paint prep?

Hey all. I've got a project going that involves about 250sf of aluminum treadplate. The owner wants it painted and I'll probabaly be going with a catylised enamel since it will live outdoors.

The plate is new and so it's pretty polished. I was wondering if I needed to wash it down with ammonia or vinegar to etch before priming?

Or do I need to use anything at all?

I believe it follows the same principle as painting chrome, plastics, no primer bare metal etc...

Scuff lightly (green Pad), clean and then use Adhesion Promoter before primer & paint...

Worked on my head light shells, no issues to date.

Here's a write up with images if interested...
kzrider.com/index.php?option=com_docman&...d&gid=455&Itemid=108

This is what we use in the airplane business to prep aluminum for painting.
alumiprep no.33
alodine 1201

anytime you paint aluminum it has to be etched-most auto paint stores sell etching primer by the quart or can actually make it into an aerosol can. most importantly, though, is the etching primer window is faily short, maybe four hours. if you wait too long the primer will seal then you'll have to scuff your surface to open the primer back up.

Is this etching and primer neccessary for painting an engine? I am getting ready to paint my KZ650 engine black in the next 2 weeks and am reading all I can about getting it ready.

Thanks!

I just painted my kz650 engine using the method I described-etching primer first then top-coated with Imron which is a very durable enamel, basically just short of powder coating as far as durability goes. The short answer is yes, use the etching primer after you have cleaned the engine thoroughly and i mean, thoroughly, then blow completely dry with compressed air and paint-2 or 3 coats of primer, wait and hour and topcoat with whatever you're using and remember,thin coats of paint set up much better than thick ones

Well, there's the good and the bad. The good is the etching wash primer worked great. I used Sherwin Williams kem 400 primer and paint with the catylist. The bad news is I forgot to get pictures of the primer. (It was 3am after a 20 hr. day.)

The bad news is today we loaded the cabinets up on the flat bed to deliver them. I didn't want to strap them down because the paint hadn't fully hardened yet and we already had a few scuffs from loading them. Only 5 miles away to the job site, and it's backroads so I could just drive real slow. I got a mile from the shop and a huge gust of wind came and rocked the truck real hard, and two cabinets eploded all over the pavement.

The good news is now I can get the pictures of the primer after I build new ones.