leaving a heavier-than-intended slurry of what's left plus accrued moisture from atmosphere You didn't mention ethanol but that's what you mean. Normal gasoli

leaving a heavier-than-intended slurry of what's left plus accrued moisture from atmosphere You didn't mention ethanol but that's what you mean. Normal gasoline is very stable, it's just the federally-mandated corn ethanol added to it that turns into sludge after a few months. Fuel stabilizer keeps that ethanol from degrading. I would advise anyone with small engines, like lawnmowers or snowblowers, to seek out ethanol-free gasoline and use that exclusively in those engines.