[nkaminar]

Leyland, The voltage is controlled by the battery. The cutout is just a switch to disconnect the generator when the engine is stopped so that the battery does not drain trying to run the generator as a motor. The third brush controls the current, not the voltage. Set the third brush to the style of driving you do and to the season. If you do short trips or drive a lot at night you will need to set it up to maybe 10 amps at a fast idle. If you do long trips and not at night then maybe 5 or 6 amsps will do. Check the battery voltage after driving. If it falls below about 12.2 volts then you need to set the current up. If you are loosing water all the time then you need to set the current down. A hydrometer will be your friend and is was Ford used when the Model A was new. If it is a sealed battery then you will have to go by voltage. Installing a voltmeter in your car in addition to the ammeter will be a very helpful tool.