Have you taken the top off the regulator to see if the cutout relay points are closing? That's the set right behind the Battery wire. As the voltage at the Armature terminal increases above battery voltage the cutout should close and connect the battery to the generator. If it doesn't close, no matter what the generator does, the battery won't be charged. Grounding the field terminal should make the cutout close pretty quickly. If the voltage doesn't rise, yank the generator and get it rebuilt.
Jerry
