I wire wheeled and acid etched till I had these little white specks of corrosion left that wouldn’t come off. I decided to use the tip of a drill and just turn each into a little dimple. Many of them made a little cloud of white dust as veins of corrosion I couldn’t see opened up and released their contents. When it was done I was left with Swiss cheese in a few spots, some I drilled all the way through. I backed all the holes, including old screw and bolt holes I won’t be reusing with masking tape and filled everything with Marine Tex Grey epoxy. It worked surprisingly well, and the tape pulled off fine 4 hours later. I think there was no real way I could have gotten everything, and there is a high likelihood some of this will progress and I’ll see it bubbling up on the outside. The new transom with be laminated with 5200, which should provide a barrier between the two layers sufficient to keep this from spreading to the new layer. I may have have a bi or tri annual maintenance schedule where I drill/dimple new spots from outside that become visible being careful not to disturb the u deleting sealant and the filling and touching up paint.
Given the condition of the part of my transom wood and the aluminum against that someone spilled oil on, I can’t help but wonder if oiling the side in contact with the metal isn’t the way to go.
I have a full gallon of Alumahawk, I’ll probably just paint the metal inside and outside
