Gas you mean? You could get gas in the oil if your floats are stuck or your needle valves are bad and your bowl drain tubes are clogged. After setting for that long you should have changed the oil before you ran it anyway. I suggest you change the oil, run a few extra quarts through to flush it, and then refill with a new filter. Run it for a bit and see if the issue returns. I'd also clean those carbs well after setting that long.
