Can Someone Who Knows RV Generators Tell Me Why Mine Stalls Please (Oceanside)

My MH's Onan Emerald Plus BGE genset needs attention.
Sometimes it starts right up and will run for a while and then die.
Other times it will make an extremely loud backfire, worse than anything ever heard on the 4th of July.
Other times it wants to start but won't.
It is located in my rig where it belongs.
Very tempermental! It was a gift to my farm nonprofit, so can't complain too much.
Can someone please help me fix it so it's reliable? I'm hanging at the beach and can offer beers, dinner, brunch and/or build you a website if you need one.
I'm a pro organic grower if you need help with your garden, too.
We're looking for farmland to grow organic food for folks in need, so if you have acreage to share, that would be awesome! Please email with your first name, your location, your preferred terms and when you are available.
Thanks!