To add to what I said earlier...

If you disconect the tank, and just squirt some fuel in the carb, it's true that you might flood it... but since you don't have the tank connected, it will eventually (within a few flips) spit out any excess fuel and since it can't get anymore, it is bound to start for a few seconds, or at least "pop".

Once you know that you're getting combustion, you can go on to attaching the tank and setting the needle