My riding mower will run for about 5-10 minutes then starts to sputter for about 30-90 seconds before engine dies. Once it starts to sputter, if I push the throttle into the choke position, it will run smooth for about 10 more seconds. If I wait a few hours to let it cool down it will start again but only run for a few minutes. Gas flow is fine (if I try to start again immediately after it dies, I can smell gas), new spark plug, new oil filter, air filter looks relatively clean. Please help!

Peter

Hi,
That is the time span for a clogged fuel cap or filter.
Peace,
Clarke

I go with Crigby. Check the gas cap vent. I just got a free chain saw because "won't run for more than a minute ". Cleaned vent and it runs fine.