Goldengoose007,
Welcome to the Stovebolt. Although I'm a green pea when it comes to these third brush units, I have read the only way to change the output voltage of the generator was to move the location of the third brush on the commutator.
Are you sure your volatge readings were good. Without physically adjusting something, one would think the system was reacting to the voltage of the connected battery....I don't know if this is possible. Maybe someone else has seen this!
Stuart
