Re: 1929 gray powdery substance found in fuel

Posted by HH56 On 2022/7/5 14:03:45

Stale gas is definitely an issue that can do damage. Even new rebuilds that started and seemingly ran well and then were put aside for a few days were, in several instances, found to have seized valves the next time an engine start was attempted. Apparently the old gas could build a coat of varnish on the stems which worked as well as glue. Doing a search on the forum should pull up some of those tales of woe. Maybe I have been lucky but cannot remember running into any old gas that I would call very cloudy or had any kind of film -- it was just sort of yellowish and stank the place up.

Not sure how you would go about identifying the powder short of lab analysis but it would be good to know for sure what the substance might be. A dissolving coating is one thing and a good cleaning then treatment with a different ethanol safe product might alleviate the issue if ethanol is causing it. While it is probably unlikely, another and worse thought is it could be mold or some other bacterial growth.

Mold growth in stored diesel fuel is an issue in some places or in cases of less than ideal storage conditions to the point of it being a real problem at times. Clogged filters are the least serious but even damaged injectors have been reported.

I don't know if there is a mold that will grow in gasoline but there are some bacteria that do thrive and eat petroleum to the point of some are even being used as something to cleanup oil spills and long term remediation of contaminated ground that was caused by leaking storage tanks. If there is a different species the gasoline didn't kill, Ethanol might have provided a medium for its growth.