MM
I had a hard time with mine so I removed the plug and checked it. It seemed dry, and only smelled faintly of gas. I resorted to an old RC trick of squirting about a 1/8 teaspoon of gas into the cylinder, reinstalled the plug and made sure the SP wire was connected correctly. After this I left the choke open (and air cleaner off) and rolled down the road. When I engaged the clutch I got a couple of sputters. This hinted at a fuel problem.
When I checked out the carb I found that the (throttle) piston wasn't moving as I moved the throttle. The little lead ball had come off the end of the cable! I guess I should have checked this before squirting the gas in, but I didn't think that could happen.
After replacing the ball the engine started... Actually, I have a small hill in front of my house and I used up about a 100 feet of it (length, not elevation) to get the engine to kick over enough to run.
Good luck with yours.