Interesting problem(s)......clearly understanding your electrical system layout is important for folks to help you out. Now we know fuse box and breaker box are the same thing:
I have re-read your first entry multiple times and I assume while on shore power you said: “Had AC into the fuse box red, black and white depending on where I place my ground lead. I searched all over and could not find anything amiss. But no AC out of the breaker box (breakers all ohmed good)”.
So you are saying you measured AC voltage Ok on the 50 amp feeder cables terminating on the 2 pole 50 amp main breaker and neutral bar (white wire) in the breaker box; (120vac red to white; 120vac black to white); breakers ohmed good (while power off of course); but no AC was measured on the output of the breakers? So I must still be missing something........power into breaker panel main breaker; good continuity through the main breakers; no power on breaker panel bus bars? I would trip that main breaker and re-close it.......measure again.
Sounds like the typical converter/AC breaker and 12vdc fuse panel box is above the bed. I would expect the shore power cable to terminate directly onto the 50 amp transfer switch, which should then feed this above bed converter/breaker panel. So if you had AC on the main breaker of the breaker panel you have continuity through the transfer switch from shore power.
You also said the gen wont start......wont crank either? If no crank, you may have an open DC breaker between the coach batteries and the starter motor for the gen. In newer coaches there is typically a 100 amp re-settable breaker near the coach batteries that feeds the gen starter and the hydraulic jacks 12vdc motor. Not sure what your coach uses. I suspect though that even if your gen starts OK and transfers AC to the breaker panel, you will not get AC on the output of your breaker panel.......I wonder if this is a main breaker issue?
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