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Alternative to Zinc Chromate for outboard motors in salt water

I do much work on outboard motors used in salt water on the east coast of the US. We typically paint the lower units (gearcase) each season prior to putting the boats in the water to protect from corrosion. The lower unit housing is made of an aluminum alloy, which we prime with zinc chromate before applying 2 coats of lacquer finish. This has worked quite well, though I'm wondering if there is a different solution that would work as good or better without chromate. There are sacrificial zincs placed in strategic areas of the motor, and the lower units I've worked on don't show any corrosion over extended periods, so zinc chromate primer seems to work well. Is there an alternative primer that I should be looking at without chromate?

Dave Koma
Hobbyist, boat owner - Havertown, PA, USA
January 19, 2010

Try www.daccosci.com/ website-that is USA firm that sells tobacco based corrosion inhibitors and tobacco powder based primers,according to them product is even better than chromate based.Hope it helps and good luck!

Goran Budija
- Zagreb,Croatia
January 22, 2010