225 charging problem

...Bypass the voltage regulator and just the regulator. In other words you are going to full field it by connecting the blue ignition wire that feeds it to the green wire feeding the rotor. This assume a grounded field alternator and regulator.
View attachment 1716124111
Observe the ammeter and the voltage at battery.
Apart from disconnecting the blue wire from the (grounded) regulator, this is exactly what I did, and reported. I disconnected the green wire from the regulator, and jumpered the ignition to the green wire. Leaving the blue wire in place with the green wire disconnected from the regulator should be of no consequence. (And yes, the alternator is grounded as well.)