Logo
FULL SITE MENU

Re-painting outdrive & hull with automotive paint?

T

theydrewa31

Regular Contributor
Hello All,

I am in the process of a restoration on a Starcraft Islander 221V. The hull is aluminum and the outdrive is an OMC Cobra.

When I was at the Marine parts store the fella there said that Moeller spray cans were the best and only options for repainting the outdrive, so I picked up some cans while I was there but can easily return them. I have taken it down to bare metal and I am ready to paint.

I have a nice paint sprayer, a large compressor and experience painting cars. I would prefer to simply use my spray gun as it performs far better than any rattle can I have ever used. Is it alright to use automotive paint on the outdrive and the aluminum hull? I would of course make sure that the paint does not contain copper. As the outdrive has been taken down to bare metal I would be using a high build primer, then paint, then 2K clear coat (the kind that you mix hardener into), finished with cut & buff for a nice shine (just like we do on cars).

For the hull I am simply covering up some spots where the rollers have taken some paint off over time, and some spots where I had some welding done on the transom, so I will not be painting the entire hull. For that reason, I was considering skipping the clear coat since it would be difficult to blend to the existing paint. Let me know if you think its better to top coat with 2K clear coat on the hull? I am trying to avoid buying that insanely expensive paint in the marine supply store, which I feel is somewhat unnecessary since the boat will be trailered when not in use. At most the boat will spend a few days on the water for longer trips to the offshore islands. The boat will be used primarily in saltwater if that makes any difference.

Thanks for any help Gents!
 
Update: spoke with my auto paint supplier. None of their paint has copper in it. No heavy metals at all. The only metal in their paint is aluminum if you get something with a metalic flake type color. From what I understand aluminum should be alright. Now the big question is whether the marine paints have something important in them that the automotive paint is missing. Again, since it isn't living on the water I assume it won't be a problem, but please let me know. Any information at all will be appreciated!

Thanks!
 
theydrewa31 said:
Update: spoke with my auto paint supplier. None of their paint has copper in it. No heavy metals at all. The only metal in their paint is aluminum if you get something with a metalic flake type color. From what I understand aluminum should be alright. Now the big question is whether the marine paints have something important in them that the automotive paint is missing. Again, since it isn't living on the water I assume it won't be a problem, but please let me know. Any information at all will be appreciated!

Thanks!
Click to expand...
Ask paint suppliers and manufacturers if their paints are made to be immersed in water for long periods.

You might want to ckeck into some of the 1K and 2K Epoxy paints that come in a spray can.

Mercury Quicksilver paint is made for outdrives and, while it's not as resistant to abuse as what they put on at the factory, it works pretty well.
 
Thanks for the reply jimn!

That's not a bad idea. Unfortunately, I already ran out and returned the Moeller primer, paint and clear coat I had previously purchased and picked up some automotive primer, paint and 2K clear coat. I have used the 2K clear coat for years on cars and it is insanely strong if you apply it thick enough. The paint I got is color matched to the OMC charcoal metallic color and I cannot return it.

This information is more for anyone else looking into automotive paint:
For 1 can of Moeller primer, 2 cans of Moeller Charcoal Metallic, and 1 can of Moeller 1 component clear (1 component means no hardener that gets mixed into the clear coat) I paid $107. I already had 1 can of primer and 1 can of clear on hand from when I had previously painted the outdrive so if you add those into the total cost as well it would have been another $45 on top of the $107 (around $160 total). For $50 more ($160 out the door) I got the can of high build primer with hardener, color matched paint with reducer, and 2K clear coat. 2K clear coat more or less means 2 component clear coat which is the type where a hardener gets mixed into the clear coat before you load it into the spray gun. The amount of paint I got would be equivalent to more than 4 rattle cans so it will give me enough to put a nice thick coat on all of the components that need it, instead of just having enough for the outdrive. Additionally I will have more than enough primer and clear coat left over for future projects (and I have a lot of projects on the list), so for roughly the same amount of money I'll be able to cover a lot more area and have leftover product. All of that said keep in mind that this would require a spray gun and a large enough compressor to keep up with the work being done, so this might not be an option for a lot of guys.

For anyone interested in 2K clear coat that does not have a spray gun and/or compressor, Spray Max makes a 2K clear in a rattle can. I have used it before and it works well. It has downsides though: 1. It is very expensive, 2. The hardener comes in a separate compartment at the bottom of the can which you break open to release prior to use. Once you break open the hardener compartment open you need to use the whole can within a day or so or the product inside hardens and the can will become useless. 3. Because there is propellent in rattle cans you are getting far less product than if you buy the product for traditional spray gun use.

I actually had repainted the lower unit with the Moeller products recently, but the clear coat was very weak and was damaged just by the wooden stand I had built to hold the outdrive while I am working on it, which is why I am re-painting it. Additionally it was very easy to burn through during cut and buff, so that told me that it was rather weak to start with. I wanted to use the 2K clear as the hardener leaves the final finish very strong. This is just my opinion but after using the Moeller clear coat I feel like it is rather weak, and mostly just provides a finished look. In my humble opinion having worked with automotive paint the 2K clear coats are much stronger, and I feel that it will actually provide more protection from abrasion than the Moeller 1 component clear I had attempted to use previously. Again, just my opinion so feel free to jump in and share your experiences or information if you disagree!

All of that said, if my boat were going to be moored at a dock full time I would definitely be looking into something formulated for marine applications; however, since my boat will be trailered when not in use this seemed like a better option for me. I also considered the fact that regardless of the strength of the paint it will almost always experience abrasion over time. Since my boat will not be moored on the water full time, I decided that the abrasion is a bigger concern than degradation due to the marine environment in my circumstance. So long story short a stronger clear coat seemed more important to me than formulation for the marine environment.

Side note, the upper unit of the outdrive held up fine with the Moeller products so I'll do my best to update this thread after she has spent some time on the water and report the differences in durability between Moeller and automotive products for the rest of the fellas on here.

Thanks again for the help everyone! I really appreciate it!
 
Back
Top