Onan 5500 Generator in Holiday Rambler 1998 Endeavor

My Onan 7500 was doing the same thing a couple years ago. It is a 2002 and I had serviced it before our trip. When I got back I took it to my RV mechanic and he found bad/ rotted fuel lines, changed them and it now runs fine. With the age of your coach this could be the problem. When I had serviced the generator I didn't check the lines and I wouldn't have been able too see them up in the service area. Good luck.