I have a Blisar GE 140 lawn tractor with MTD engine (see appendix ) and the following problem: If I have already mowed about 20 – 30 min the engine suddenly goes off and does not start any more, before it runs short unround and the performance fails. I have already replaced spark plug and cleaned air filters. Gasoline supply seems fine, pulled the hose next to the carburetor and there was plenty of gasoline out of the line. Hose again mounted and waited about 20 min. R jump again and mown for about 30 minutes. Please for solutions ??