[special-K]

I'd crank some Sea Foam into the carb (pull coil wire first), let it sit an hour, and start it up for a while. Could save you a rebuild. I think it's ethanol causing moisture to accumulate. That's moisture, not water, crappy murky sludgy liquid yuck. I had a rebuilt carb fountain up after I had dealt with the truck's ethanol related issues before putting the carb on. I was very thorough with flushing the tank, but did not remove it. I did a series of purge with air/flush a couple fresh gallons/purge/flush... The truck had been running fine and with the buyer an hur and a half out I started it up, ran a few minutes, got all fluttery, and stalled. I look under the open hood and it's the fountain of gas! It seemed like gas was coming out everywhere. I did the Sea Foam trick and when the guy showed up I fired it up and pulled it on his trailer without a sputter.