Simplicity 25 hp Legacy with Kohler Engine

Engine shuts off then will start right back up, sometimes if I shut the mower off quick enough it will keep running but not all the time. Does not appear to build up smoke. I thought it might be a clogged fuel filter so I put a new one on, it ran good for 30 to 40 minutes then it started that shutting down again. Two weeks ago I put a new air filter on. Back to fuel filter, if it sits it will partially fill up but when it runs the filter seems to empty. Anyone have any ideas what the problem is?

Check the has cap that the vent is not clogged . Ethanol in unleaded is melting the cap vents inside .