Small Engines (Lawn Mowers, etc.): 19HP Kawasaki stalls, scag tiger cub, kawasaki engine

Question
Ben,
I have a 2003 Scag Tiger Cub with the 19 HP Kawasaki engine (FH601V I think) that I use to mow 1 1/2 acres.  Has approximately 125 hours  on it.  The mower starts and runs perfect.  The mower frequently dies after about 30-45 minutes of use.  If I mess with the choke and throttle it will kind of sputter for a few seconds but not run.  It I let it sit for 20 minutes it starts back up fine and runs perfect again.  Recently changed fuel filter but did not help.  Any ideas?   Thanks, John

Answer
John
Have you checked the fuel tank for dirt if you can look in there to see sometimes dirt will settle in the fuel screen and slow the fuel flow. Another possibility would be that your carb needs cleaned out.Also you can close the gap on the spark plug a tiny bit from 0.030 to 0.0025