Have a 9650 walker, and starting last fall in beans, it randomly dies, now it has only happened while cutting, it hasnt happened while being roaded between fields or back to the shed. To get it started, you have to go upstairs and prime it and it will start. Have not found any broken wires or leaky fuel lines anywhere. It happened 3 or 4 times this weekend in wheat. Has anybody ever experienced this before or heard of it happening?