I have used SeaFoam at one ounce to one gallon of gasoline in all of my outboards, and all of my power equipment for six years. Never have seen any kind of chemical reaction like that! The fact that you processed three tanks the same way, then filled them with the same fuel mix, makes me wonder, like you, if there was a reaction to some remaining deposits in that one tank. I think we need an Organic Chemist to weigh in. :geek:
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