- Feb 22, 2021
- Waco, Republic of TX
- Kubota L3200
I wonder the same thing. All of my gas engines will run fine on gas (+ethanol) right out of the pump. But how long till that gas goes "bad" is highly variable and seems to depend on lots of factors out of my control. The chainsaw is the canary in the coal mine. Recently it wouldn't start on gas that had only been in my 5 gal plastic container for 6 weeks. The mower still runs on it just fine, bigger engine I guess, but what changed that much in only 6 weeks??I'm wondering if it's a regional thing, refinery related, climate? I don't know. I store the gas in sealed plastic jugs, if that makes a difference to anyone. I don't drain my tanks of fuel. The exception might be the chainsaws, as when I'm cutting firewood, if it runs out of gas for the 4th or 5th time of the day, I'm usually worn out, so I leave it empty.
Back to OP's original question -- the chainsaw definitely likes that expensive pre-mix high-octane ethanol-free stuff from the farm/ranch store. That gas keeps forever without adding anything, and won't vapor lock the saw in hot weather. Second best is buying ethanol-free gas from one of the two stations in town that sell it (at premium prices), although I don't what other baloney they put in.