I'm still squarely un the "fuel problem" camp.
Im not sure your motor has a fuel pump. If it doesn't then your carbs have a diaphragm pump that gets hard. For that matter an electric fuel pump does too.
I just changed the fuel pump on my generator. If I primed it (electric primer, not a choke. Just like your motor) the generator would start but usually die pretty quickly then not start again. Sometimes it would run fine but became worse and worserer.
If I was home I'd dig I to it for ya but I'm not expecting to come home until July.
Sent from my SM-G960U using Crappie.com Fishing mobile app