I've tried to keep track but have been unable to determine roughly how many tanks of gas (15 ga) I can get out of one full reservoir (1.6 ga) of oil? Anyone figured this out?
It's variable... so it's not going to be the same all the time. At full throttle, you burn about 40:1. (3.2 oz/gal) So... at full throttle... you can burn 64 gal of fuel. that would be a little over 4 tanks of fuel.
I always top my oil tank off after every 2-3 tanks of gas,so I'm not sure. I burn approx 3 gallons of oil per ski in the summer, at approx 50 hrs / summer run time. in any case, keep the oil tank full, and you can run many tanks of gas no problem. run out and you will be rebuilding that engine in no time