Mercury 225 Pro XS, worked fine when unloading. Fished for an hour and a half, went to start it and it started but immediately died. Turns over but won’t start, checked kill switch and to make sure it is in neutral. Gear shifter is really stiff but it is in neutral. Turns over and smell gas but won’t fire. Two tanks half full so it is not gas. Any idea of what to try to get it started?