"Since gasoline already contains virtually these same ingredients (ethanol and a small amount of naptha), what exactly do you expect this to accomplish?"
Not quite. Ethanol and isopropanol are different alcohols. And "gasohol" typically is E10, only 10% ethanol, nowhere near the amount found in SeaFoam. Among other things, running that high a percent of alcohol instead of regular fuel
would burn out the plastics and rubbers used in most fuel
systems, they're just not designed to resist that much alcohol of any kind.
As to things not being in the MSDS...in this case, there are no "trade secret" or similar ingredients shown. There's not even a claim
that there is any magic in the bottle. The only claim is that the stuff will blow out carbon--which many things will, no secret sauce needed. Really, just old coffee will do that, as the water
superheats and the steam blows out the carbon.
out carb jets, high end solvents like GumOut will do that to some extent. If you put them in the fuel (and since the 90's all gasoline has had way more detergents in it, in the US) they will help somewhat. But in order to really clean out any accumulated varnish
, you still need to take it apart, soak it in pure solvent for several hours, and physically clean it out. If you stick to the "top tier" gasolines, they claim to have enough detergent and magic in them so that varnish
should not be a problem in normal use any more. That also means not letting gasoline get more the 90 days old, at the most. Or adding Stabil or a similar product. Their MSDS shows something like 99% naphtha, with yes, just one
percent of magic. Which is also proven to work. And, a trade