I just changed the oil in my tiller, started it up and it run fine (No smoke) after running a couple of min's it began smoking and running rough. Turned it off and checked the oil and there was gas in the oil I had the gas turned off, replaced oil, cranked it again and checked for gas and there was still gas in it where is the gas coming from? Could it be thru the value or ring?

need a model number off your motor to help you

Could be the needle is stuck open, letting gas flow all the time. It the fuel tank gravity-feed to the carb?