I know not apples to apples , but our Generac we had , on a trip it ran just fine the night we boonedocked (spelling?) ran for about 2 hours.
Didn't use it for a few days , then needed to so went start it and wouldn't stay running .Went out lifted up the cover and tried to start it with the button on the gen samething started looking and kinda moved the throttle linkage around and I guess it was the choke linkage slipped back and I tried to start it up again and ran perfect.
I had a can of WD40 and just kinda sprayed the linkage. Never had another problem with that part of it..
So maybe the choke linkage was binding or ?