Small Engines (Lawn Mowers, etc.): honda gv400, rideon mower, gas cap

Question
i have a rideon mower that runs well for 15min then backfires and stops. so i stripped it down cleaned all fuel lines jets in carbi replaced gaskets new sparkplug and no difference and just starts please help me

Answer
Sam

Sounds like your valves need adjusted,as they get hot they expand and don't fire correctly.Have you tried running it with the gas cap loose? Sometimes the vent in the gas cap gets plugged and the fuel pump can't pull against the vacuum created in the tank.
Also Sounds like your coil is what is giving you problems. Next time it quits check for spark.