I had the same issue. I use the same engine on a snowblower after changing the crank. It would consistently shut off and then restart without hesitation. I ruled out a lean condition as carbs will surge much longer than once or twice before they conk out if they ever do. The red light would flash on the on/off switch indicating a low oil condition. Oil lever was fine. I wasn't sure if it was a NO or an NC switch so I started it and cut the wire. the engine kept running and has never shut of again