What exactly happens?
This is the result of bio fuel/ sunflower oil /ethanol being mixed with fuel…
Unlike pure gasoline, biofuel is… Well.. bio and it degrades rapidly… This clogs fuel systems
Normally this isn’t an issue, because it’s flushed with other fuel, but when you leave it, it blocks the path.
Lot of chainsaws, lawn mowers and other “seasonal” tools get thrown away by people who don’t know why they suddenly don’t work
Pro tip: run it on pure gasoline until you empty the tank if you know you won’t use it in a while
[I think this is a great starting point for your question about that.]([https://www.youtube.com/watch?v=chsGBhB5g7o](https://www.youtube.com/watch?v=chsGBhB5g7o)) In a nutshell, higher molecular-weight components of the fuel get oxidized while lighter ones evaporate off. The heavy stuff becomes “varnish” that interferes with carburetors. And people saying “ethanol” are dinosaurs who need to go back to school to learn what is right, and what is wrong, about what they’ve heard about gasoline in recent decades.
Over time gasoline breaks down and partially evaporates to the point that it becomes gooey or sludgy, any gas that was inside the carb will pretty much become glue and need to be cleaned out with solvent (this will also clog fuel lines and injectors too)