RV Repair: Old Onan Generator wont start, pace arrow, onan generator

Question
I recently purchased a 1984 Pace Arrow 31 ft that has a 6.5 KW Onan Generator s/n 6.5
NH-3CR/16004P that has 140 hrs on it. I know that it has not been used for a few years.
From the generator itself I hit the Start switch and it cranks nice. Gas is getting to the carb. I
replaced the plugs. It does not start. I am  pretty sure that it is electrical. Is there a switch
inside someplace that would prevent it from starting? I am new to these things. Will it start
if I am plugged into shore power? Any ideas?

Bruce

Answer
There should be a main start on/off switch inside the cab, most rigs have that main start inside so you don't have to go outside to start it. And I know the newer rigs have a prevent start when plugged into main power, not positive about older models but your best bet is to unplug your rig and try to start it....And be sure your getting spark from the plugs if you already haven't.