thanks for responding i have a 25 year old kubota b 7200. it has not been charging adequetly for a few years. 3 or 4 years ago i disassembled the alternator and cleaned out lots of dirt and it charged marginally for a while longer but now the charge light stays on, again. i also had disassembled the dash cowl,fuel tank, firewall,etc. to view the regulator. seems like it was maybe two inches by two inches by six inches long, aluminum, with many cooling fins. the alternator has two brown wires leading to it. i have learned to test generator output by touching a hot wire to the field terminal ( or grounding it according to the type) but i do not know how to test for for output on an alternator. this i need some help on. i assume that if the alternator checks good the problem lies with the regulator, unless i find a bad connection. some advice would be most helpful and appreciated.