i have a 15.5 craftsman tractor model: 917.271011
last year it started to stall after it was hot - about a half hour.
this year it started right up and ran for about 45 minutes before it stalled. then started and only ran for about 1 minute before stalling again.
now it starts fine and runs for only about a minute each time.
??????

GEORGE, May 2011

Is it running rough with black smoke?most probably a blocked air filter, renew filter and spark plug.If no black smoke out exhaust (running rich) then could be fuel delivery problem(running lean)a blocked jet in the carburator or fuel filter due to contaminants in the fuel will have to clean out,fuel cap not venting. A tight valve or loose valve seat can cause it to cut out. Cuts out dead could be ignition system either igniter coil or safety system fault, switches that kill the spark or fuel stop solenoid on main jet.The trick is to pin point the problem

Dave Fix, May 2011