The mystery remains a mystery. Coach is level and full of gas. There is no fuel filter anywhere I can find. There are no leaks anywhere I can find, nor loose fittings. No breakers of any kind tripped.
The next morning it started right up again, though it acted very strange, and would not start from the control on the unit. But when I hit the start button up in the rv, it started normally, albeit it still takes five to eight seconds of cranking to start.
the only way to really test the gen is to run it for another hour under load, but it bothers me it would just cut out for no apparent reason. Which leads me to believe that the fuel pump is very, very suspect. BTW it is a 4kw Onan, not a 2.5 as previously written.
We are off tomorrow to our first rv campground with full hookups, so we won't need the gen, but I'll test it anyway. And then the following week the rv goes back to the dealer to get suspension upgrades put on, so it looks like the gen can wait until then to get looked at, and for sure check for a recall.
thanks for all the suggestions, I really appreciate it.