682 problem

[ramman16248]

I recently had the carb rebuilt on my 682 by a guy who is really good on carbs. ( He has done a few in the past for me and I was extremely pleased with the outcome). It ran fine when I got it home. I used it a couple of times mowing once and dirt blading with the snow blade. ( Maybe less than 1 tank of fuel). It sat for 2 weeks untouched. The next time I went to use it, the weather was a little colder, but not cold. ( Sweatshirt, not coat wearing cold). The tractor was difficult to start. It only ran with the choke pulled 1/4-1/2 way out. It ran fine then. Fast forward 3 more weeks. I bought a barn find 48 Plymouth. I loaded the 682 on the trailer in case we needed it to help pull the car to the trailer. The tractor wasn't needed, so I loaded it in the back of my truck and it stayed there for 2 weeks parked outside my garage. When I started it to load it in the truck, it started ok, but now the choke needed to be half way out to keep it running. It didn't miss or backfire or anything, just would run unless it was halfway out.
Now after 2 weeks sitting outside on the back of my truck, I can't get it to fire and run for more than 2 seconds. Those 2 seconds are probably from the starting fluid that I shoot down the carb. It will run good until the fluid runs out. ( Anywhere from 2-10 seconds.) Could the carb be screwed up, or possibly a fuel pump? I know I turned it over until the battery weakened, and I don't think it smelled flooded at all. Most Cubs I had in the past would have smelled like a fuel spill by this time. Where should I look first? Thanks, Jason