Onan 4000 MicroQuiet - Quasi No Start (new carb needed?)

The float bowl on most carburetors must be vented to the atmosphere to work properly. From your description, it sounds like your float bowl vent might be plugged or the float itself (needle and seat) is stuck. 160 hours use in 5 years is low, IMO. Is this genny being exercised regularly? (I suggest 20 minutes, once a month, every month)

Chum lee