Alodine
Peter,
I would be VERY suspicious about doing as those directions tell you. FYI, you MUST allow any Alodined part to dry at least over night [preferably at least 24 hours] before doing any priming. The metal needs at least that long to completely dry. Otherwise you risk trapping minute amounts of moisture between the metal and the primer [not a good thing]
Priming ASAP [once the metal is truly dry] is best, simply from a contamination standpoint. When you etched and Alodined the parts, you got them totally clean. Letting them sit around before priming to long will allow dust and debris to accumulate on the metal's surface. That's not ideal for primer adhesion. That said, you can use any one of numerous products to clean the Alodined aluminum, if you can not prime in a reasonable amount of time. It simply adds more work to the equation.
Alodine [and it's competitors, Iridite, Durado Kote & Divercoat] improve the adhesion of the primer to the aluminum, compared to priming bare aluminum.
Charlie
PS Once you Alodine the surface, you can not simply drop the parts back into the solution and expect any change. Once the Alodined surface dries, no further chemical reaction will take place. You would have to either mechanically remove the Alodine or soak the parts in the etch solution for an extended amount of time, to remove it.
