THE LAST TWO TIMES I WAS ON THE LAKE WHEN I WOULD START THE MOTOR IT WOULD START FINE AND RUN GOOD FOR ABOUT 5 MINS AND THEN IT START MISSING LIKE IT WAS NOT GETTING GAS AFTER A FEW MINS IT WOULD START RUNNING GOOD AGAIN FOR THE REST OF THE DAY.COULD IT BE SOME BAD GAS? I HAD IT TUNE UP IN MAY.