If that was the case, my "just spray it on" method of painting my lower would show tremendous "sand blasting". I cruise at anywhere from 30 - 50+ and run short term 60+ and have zero dulling at all.
It looks like it's the entire surface of the lower only which is odd. At speed, the whole lower isn't submerged completely. My guess is something to do with the way it was painted or prepped.
Jim
I think it may have more to do with the material ingrediants in the Zinc Chromate primer more than anything else. I believe there was some type of reaction caused possibly by the Mercathode or between the primer and the finish coat. After scratching my head on this one, that was the only conclusion I could come to so I decided not to use that primer this time. Instead, I just used just the regular Mercury grey primer instead. We'll just have to see if this dulls up as well. But ultimately, I am more concerned how the outdrive holds up to corrosion than about how shiny the paint is. I am determined to minimze or eliminate my corrosion. On my next haul out, if I am still battling corrosion, I am going to get a hold of Mercury. There has to be a way to deal with the corrosion problem on our lake. And after looking at other folks outdrives in the lake, I guess I should feel somewhat "fortunate" that mine is only lightly corroded compared to theirs. I have seen some really nasty looking outdrives. I think I may have to start taking pictures of some of these drives so I can show people what I mean.