Hmm....I found a quart of RUG in a container (closed 2 gal fuel can) in my garage that I had used to thin SVO in the summer....so I just poured it in my tank....I then added 5 more gallons of diesel following adding the rug. I doubt it will even notice it.
whats a quart of gas vs 20 gallons of diesel (tank is/was full)
I don't believe that gas goes completely bad over time. We've left our lawnmower, outside, burried in snow, with a mostly full tank of RUG all winter long, come spring, I prime it a few times, and fire it up, generally starts on the 1st or second pull, lets you know for 15 seconds or so with some blue exhaust, then it clears up and runs great.
I then change the oil once the engine is hot. I use 5w30 Valvoline dino oil in our mower. (5.5hp Briggs&Stratton Intec engine)
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