Metal Gas Tanks and Ethanol
OK, we're all familiar with ethanol being detrimental to small engines as small engines tend to sit with fuel in them. This leads to water build up, carb jet issues, etc. Another issue with small engines and ethanol is the older engines tend to have metal gas tanks which do not like water. I discovered this in a roundabout way while restoring a '74 JD tiller with a H60 Tec with a metal gas tank. Inside of the tank was a disaster and I researched gas tank coatings. Discoverd that there are posts on other forums that ethanol (alcohol) attacks some coatings. Sent an email to POR and asked them. They responded that their product is tested with 100% ethanol with no problems. They also suggested they have an additive which is formulated to offset this problem.
This led me to look at some of my other old engines with metal tanks and was not happy with what I found. I guess I'm going to be doing some cleaning, coating and cursing this winter.
Not a Shill for these folks, never used these products, but was impressed that they're aware of the problem and have done some testing.
I've attached a link for the fuel preservative. The tank coating is also there if you look around. amazon seems to have the best price.
Here is a link that might be useful: POR fuel preservative