Onan starting amps and wiring
I have been redoing the 12 volt battery, charger, inverter, alternator wiring on our 07 C190P Roadtrek, and one of the wires I ran into that I didn't expect was a 12 volt wire to the Onan generator, presumably for starting. It looks to be a #8, right off the battery tie point, about 6 feet total length. Since it was tied into wiring that I planned on moving the connections from that area and putting them into the main electrical area, I figured I would extend the wire to that area. I planned on fusing it, so I looked up the starting amps in my Onan manual----180 amps at 0*F. Holy, c... They recommend #2 wire to start at -20*F. Even the 180 amps at zero would need @2 to have the 1 volt max drop they want. Do the other brands of B's cheat as much on the start wiring as Roadtrek does?
This does kind of explain a problem that seems to come up on the Yahoo Roadtrek board all the time, gennies that will not start on the batteries, but will with van engine running. The extra couple of volts the alternator gives compensates for the loss in the small wiring.