To me it is "quaint" to hear about "methyl hydrate" as an old name for CH3OH known as methanol, methyl alcohol or even wood alcohol, but it is true that they (IUPAC, International Union for Pure and Applied Chemistry) come up with changes in the ways to name chemicals every few years. You can buy this stuff as "Dry Gas" for a tank additive to absorb moisture in the gas. A little CH3OH in the gas will reduce tank moisture and be pretty harmless, but we should know from the "Gasohol" fuels with higher percentages of Ethanol CH3CH2OH that various gaskets and tubing in the fuel system may or may not swell, leak, be dissolved or otherwise misfunction due to the CH3CH2OH in the fuel. I would expect that high percentage of "methyl hydrate" would eventually effect older fuel system gaskets and plastic tubing. Newer cars since about 1990 should have materials in gaskets and tubing to handle Gasahol and should not be effected by CH3OH either, but older carb gaskets or see-through fuel lines might get gummy and/or swell up with high percentage amounts of CH3OH. Of course an occasional pint container of Dry Gas thrown into a tank of fuel will be a very low concentration and not harmful. Of course most of us know that you should not drink CH3OH as "wood alcohol" because it leads to blindness. For biological reasons our digestive biochemistry can process alcohols with an even number of carbon atoms so CH3CH2OH and CH3CH2CH2CH2OH can be digested with accompanying drunkeness, but CH3OH and CH3CH2CH2OH (rubbing alcohol) are poisons. Just some factoids about low molecular weight alcohols. The comments about using engine cleaning with water through the carb are very interesting, but I would think that windshield wiper fluid might be pretty good too, even better, due to the isopropropanol in it (a form of CH3CHOHCH3, an isomer of propanol with the -OH on the middle C atom instead of the end).

Don Shillady
Retired Scientist/teen rodder