on most small motors I have found that adding some "alcohol" actually improves the running of them, as any water in the system will move through.
(one factor, alcohol is not a volatile as gasoline so it does not vaporize as fast, also it burns slower (higher "octane" rating), and normally to get a good alcohol running motor the compression and normally you need larger jets in the carburetor,
It is a different fuel, and the characteristics of burning it are different,
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It is that it does not eat the metal pipelines as much as it cleans them, and they can not afford to have all the "crud" broke lose in the pipe lines, and many times they use the same pipe for many different items, they send one batch of some thing through and then something else, through and so on, with ethanol (why it kinda got a bad name to begin with on filters and so on as it broke all the varnish and other crap loose in the fuel tanks and lines plugging the filters, and once it is clean any pin holes that were plugged or nearly through can corrode usaly by other contaminants again forming a hole,
(yes it is hard on rubber parts) again not being formulated correctly for the chemicals that they should have been designed to possibly carry,
and the corrosion seems to Be more when the fuel is contaminated with water or other,
what I read is actuly happening is the cleaning action of the ethanol cleans the materials and then other things then can attack some metals such a s soft aluminum, as there is a galvanic action that can occure.
it is not that they could not have built a quality product, but that they apparently chose not to, as ethanol has been on the horizon ever since the 1970's and Brazil ran nearly 100% ethanol for years, it is not that they do not know how to build to resist the cleaning actions of the alcohols, but that they chose not to.
and now blame it on the fuels not there lack of building a quality product.
on some fiberglass products the resins are not compatible,
http://www.searay.com/pdf/ethanol.pdf
http://www.in.gov/idem/files/la-072-gg.pdf
http://www.nmma.org/lib/docs/nmma/gr...tion_Paper.doc