Best guess?
Model 445877-1565-g5 in a craftsman yt4500 won't start without starting fluid after it sits for a couple days. If I run it for bit then try to start the next day it will usually start right up as normal but if it sits for more than a day it usually requires a quick shot of starting fluid. It doesn't appear to matter if gas tank is full or near empty. Once started (and it starts easy with the starting fluid) it runs great. The next day it takes about 5 or so seconds (no fluid).
What's the most likely culprit?
#2
StarTech
Choke not fully closing is one possible. Fuel bowl might have a pin hole if it has the steel fuel bowl.