Well.... I highly doubt that the carb is the issue, but since you already have it off, just as well go ahead and rebuild it. I don't know why you "local" guy can't figure this out, as it's pretty simple and very, very, very available. Look
here at the parts breakdown. Part number is right there. I might add, that CCC wants a pretty penny for that kit. Plug that number into Google and I'm sure you can get it cheaper. I'd get one from Primeline, or Stens which most all auto part stores carry.
Anytime you need parts, just go to cubcadet.com and choose "parts and service". Plug in your model number to get the parts book for it. Pretty simple and easy to look up your own parts. Obviously, the kids at the parts store are too ignorant to do it for anyone.
Moving on: Likely the fuel pump is bad, or the tank is plugged up.... or you may even have a failing coil... the coil is what I would put my money on as 15 min of run time is a pretty long time for it to starve for fuel. If it will run that long, it's likely getting fuel. After you rebuild the carb, flush the tank, replace the fuel line, check the fuel pump... make sure you take the pet-cock out of the bottom of the tank and clean or replace it, as there is a screen, (replace the o-ring on the tank also) then fire it up. If it dies again, check for spark. You will likely find that your fuel issue is actually electrical.
Good luck.
