Re: Do I need anode(s)??? Outdrive painted?
You can't just spray or brush paint on to aluminum like you can some other metals. The aluminum needs to properly prepared and primed. Here is Mercruiser's "Factory Authorized" procedure.
This if from the Mercruiser Website
http://northamerica.mercurymarine.c.../mercruiserfaqs/technicalinformation.php#1135
Refinishing procedure:
This procedure should be used in refinishing MerCruiser sterndrives and transom plates. This procedure will provide the most durable paint system available in the field. The listed materials should be purchased from a local DITZLER AUTOMOTIVE finish supply outlet. The minimum packaged quantity of each material shown is sufficient to refinish several sterndrives and transom assemblies.
1 QT. DX-533 Alumiprep #33 metal preparation
1 QT. DX-503 Alodine #1201 conversion coating
1 QT. DP-40 Non sanding Epoxy Primer zinc chromate primer
1 QT. DP-401 Catalyst for DP-40
1 QT. DAR-9000 Acrylic Enamel-black topcoat
1 Pt. DXR-80 Delthane Ultra-additive for acrylic enamel
1 QT. DTR-602 Acrylic Enamel Reducer-temperature range 70-90 degree F.
PROCEDURE:
1. Scuff sand to remove all blistered paint and roughen factory finish. Remove sanding dust.
2. Follow manufacturer's recommendations and instructions on the individual containers.
3. Apply DX-533 (Alumiprep #33) to clean and condition the aluminum.
4. Apply DX-503 (Alodine #1201) brush on chemical conversion coating for aluminum.
5. The DP-40 (Epoxy Chromate Primer) mixed with DP-401 Catalyst can now be applied. A .75 mil film build is recommended.
NOTE: Allow 30 minute induction period for permeation of the epoxy chromate primer and the catalyst prior to application.
6. The topcoat consists of DAR-9000 Acrylic Enamel Black and the DXR-80 Delthane Ultra additive, and DTR-602 Reducer. It is a polyurethane acrylic enamel system which provides fast drying, durability, high resistance to corrosion and good color and gloss retention.
7. The type of spray gun used will determine the proper reduction ratio IMPORTANT: DO NOT use any type of aerosol spray paints, as the paint will not properly adhere to the surface, nor will the coating be sufficiently thick to resist future paint blistering.
NOTE: DO NOT PAINT SACRIFICIAL ANODES.
Some people are having good success with Epoxy instead of Acrylic based paints and are not using zinc based primers (for corrosion reasons), but unless you are going to strip all the paint, I think the above is the way to go.
