Obviously, I am preaching to the choir. But I had some straight gas left over from lawnmowing season and my snowblower is 2 cycle and needs an oil/gas mix. I mixed a small, slightly rich mixture in a volumetric container to get it running in early December.
But I still had gas left over and it needed a refill. I have two identical gas cans, so I weighed the empty as a tare weight and the partially fully one. 1850 g - 641 g (tare weight) = 1209 g gasoline Gasoline density is about 0.74 g/mL, so 1634 mL gasoline. My snowblower likes 48:1, so 34 mL of oil Would have been a PITA in pounds, gallons, fl oz. Note: The gasoline isn't too old because I use my lawnmower in November with bagger to pickup leaves. Last use is the day I put it away and get the snowblower out and ready.
