The new VDO voltmeter has been reading low since the beginning. There was a short time between initial set up and final installation when it seemed to be reading right, but after I tucked all the wires away it went back to reading 10 volts at rest, maybe 11 or so under power.
I charged the battery, added water, checked the generator’s brushes and all the connections. Starting to think it might be the gauge. Either that or something I’ve not yet discovered about the way I wired it.
Today I put the multimeter on the battery and started the engine. The meter went from about 12.6 before the engine was started to about 13.8 volts after. And the new VDO volts gauge?