Painting Outdrives and Tabs

echandler1971

I have a few questions to bounce off of the knowledgebase here. Early April, I plan to carefully-disassemble the 2 transom mount assemblies into 3 parts (x gimbal, y gimbal, and trans assembly left attached to transom), sand blast them, prime and paint. They are looking pretty bad with the transom plate being riddled with unreachable barnacles. The outdrives are in indoor storage who knows where at the moment, but I'll do the same to them when the marina reinstalls them. Anywho:

1. I would remove the zincs, but it has me wondering if the zincs need to be in contact with metal to some degree when reattaching them, or can they be attached to painted metal afterwards? I'm assuming that if anything, the bolts holding them on would make this connection if it was necessary. This question would also apply to the trim tabs that will be getting the same treatment as above.
2. My plan is to sandblast with medium grit AL oxide, prime with 10% thinned InterProtect 2000E and then apply Trilux 33. Does this seem like the right thing to do?
3. I'm wondering if the mount for the fan on the bow thruster should be treated similarly, rather than just getting bottom-painted like it is now.

Thanks

LaRea

Paint all surfaces.  The anodes make electrical contact through the bolts, not through the surface.  When you buy a new outdrive, all surfaces are painted.

I'm not sure Trilux is durable enough to serve as the primary coating.  You might need some other product, with Trilux as a final anti-fouling layer.  The factory finish is a hard coating -- probably some sort of epoxy. 

echandler1971

Pictures uploaded out of order. Sand blasted, then sanded, primed 2 coats, antifowling 2 coats. 

echandler1971

also, I decided not to disassemble the transom assemblies, only because when I went to do that, the marina had put the outdrives back on. Next year maybe? Who knows. Also, I learned that Pettit interprotect 2000E is similar to tear gas in that if you apply it and don’t wear a mask and eye protection, it sneaks up on you and you end up laying down in the back of your car in tears, fire in your eyes and and nostrils on fire for an hour. 

LaRea

Yikes!  Any lingering effects?

echandler1971

LaRea said:

Yikes!  Any lingering effects?

Nope, but a new warning memory is burned into my brain. 

Aqua_Aura

The anodes would be best if they are also touching the clean metal as well as thru the bolts. You can do a resistance test with a multimeter and touch one lead to the anode and the other to the metal it protects, there should be little to no resistance.