Switching from a generator to an alternator When electrical problems are encountered, owners can go in one of two directions: maintain the generator based system or switch to one based on an alternator. For those who prefer originality, here is a link to a page with a discussion on Fergie electrics, featuring excellent diagrammes of the original wiring for both the 12 volt TEA and TEF. (When you get to the page scroll down a bit where you will see links to the schematics.) Switching over to an alternator-based system can be less expensive than repairing the existing generator-based system, and future repairs may be less costly if the alternator is a common model. In North America a very popular unit is the Delco 10si; it was used for many years on GM cars and is widely available at low cost. Its built-in regulator makes wiring very simple. To read more about it you can check here. The toughest part of switching to an alternator is making mounting brackets, and dealing with the Fergie's wide fan belt. I have done this conversion on my Triumph TR3; it's not identical but may give you some ideas. Since tractor engines run much slower than car engines, it may be a problem to get the alternator to start charging. "Gregg" writes on the Yesterday's Tractors Discussion Forum: "The one-wire regulator.needs to be spun up fairly fast before it will start to charge. After it starts to charge it will continue to charge at low rpms. There are two different regulators; the good one does not need real high rpms to energize the system. The number for the non-self energizing regulator is Blue Streak # VR-111; you will  need all three wires hooked up for this one to work." The drawing below was done up by John Billingsley. He has more of them at this webpage. Things to note about this drawing: 1. The ignition switch can serve as the terminal block i.e. they can be a single unit.. 2. You could use a 12 volt coil, but be sure to determine whether it requires a ballast resistor or not (some do, even though they are called "12 volt").. 3. "Safety Switch" and "Solenoid" are a single unit: the switch operated by the gearshift on top of the bell housing. 4. If you have an alternator that is truly "one wire", leave out the wire with the diode. If you are concerned about the leakage of the alternator's internal regulator draining the battery, you can put a switch in the one wire that can be turned off when the tractor is not in use.