I have lots of carbureted 4-cycle engines around the house from an 18hp lawn tractor to an 8hp roto-tiller, to a 10hp snow blower. I never have trouble with them sitting around for extended periods. I apply the same to my 4-cycle Onan which also never gives me trouble.
I just don't understand why everyone else has so much trouble with their Onan sitting without starting so frequently. It must have something to do with sitting outdoors, or they don't know how to prime it after so long of a period. Mine 4-cycle engines are all stored indoors which I am sure is influential, but still.........