Outdrives are difficult to keep free of growth. The main reason for this is that traditional copper-based bottom paints cannot be used on an aluminum outdrive. Doing so will result in serious corrosion from the aluminum reacting to the copper in the paint.

When painting an aluminum outdrive you must use a copper-free bottom paint. There are a couple of different brands out there. Interlux Trilux 33 (The most popular) , and Sea Hawk Mission Bay (The best). Trilux is the most popular and easy to find at your local West Marine. However, the results are not as impressive as Sea Hawk Mission Bay that uses the newer zinc technology. You will get the possible results with Mission Bay, and is becoming more and more popluar as the best solution for painting an outdrive. It is also the best priced of the two and is available in an aerosol spray, gallons, and quarts.

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How to Apply Bottom Paint to an Aluminum Outdrive