i have a 48'' bobcat with a kawasaki kc420V 14 HP engine. I cut 2 lawns today no problem but when i got to the third it ran for about 5 minutes and started to make a wierd cycle noise as ifit were low on gas. The gas tank was well over half full. It started again but again cut out. I had to resort to the 21'' for the 3rd lawn. I emptied the gas bulb under the carb and tried to clean the very dusty air filter. It ran for about 15 minutes so i cut half of the 4th lawn and it cut out. I gave up for the day because it was already 9 PM. Tomorrow i am going to go buy a new air filter and gas filter. Any other suggestions? i need to mow 2 and a half lawns before saturday because i am going away. Thanks for the help.