Alternator voltage regulator

I received a voltage regulator from Yesterdays Tractor to put on my IH Cub. This regulator in exactly like the one that was on the tractor when I bought it in 1986. Since then I have gone through a couple of automotive voltage regulators. I forget how the regulator that came with the tractor was wired up. Can anyone explain the connections? I think;
L goes to the start switch.
Batt goes to the ammeter.
F goes to the alternator field
Do I use the Gen terminal?

FOUR WIRE VR WIRING (For Generators NOT Alternators)

YES you must use the GEN Terminal

BAT to Load (NOT battery/starter) side of Ammeter

GEN/ARM to Gennys ARM post

FLD to Gennys FLD post

(L)oad to feed hot battery voltage to loads like lights and ignition. It often wires to the BAT Input terminal on lights or ignition switches

On many 4 terminal VR"s the ARM/GEN terminal is underneath or off on one side all by itself.

John T

Do you have an alt or generator. That regulator is for a generator.

good info so far
more good info on farmallcub.com
good luck
Ron

I have a 3 wire alternator, however a regulator like this new one was on the tractor when I bought it and it worked for a long time, or at least the ammeter said it did. I just raised the hood to replace the wiring which wasn"t properly sized when it was converted. Given my memory lately, I will be the first to admit I am wrong about the regulator.

IF THIS TRACTOR has a Delco internal regulated alternator on it, YOU DO NOT NEED THE REGULATOR that was originally on the tractor. Wire the alternator as follows. Bat. terminal alternator to the Amp Meter. The 1/4 inch blade terminal to the right/clockwise from the Bat. terminal looking at the rear of the alternator need to be connected to a switch 12 volt source through a 10 ohm/10 watt resister or a diode with the band on the diode towards the alternator. The next 1/4 inch blade terminal to the right/clockwise need to be connected to a UNSWITCH 12 volt source. Many people connect this terminal to the BAT. terminal on the alternator BUT this is NOT REALLY right. I like to connect this terminal to the same terminal the battery connect to on the starter switch or solenoid. You may say this is electrically the same point as the BAT. terminal on the alternator BUT IT IS NOT.

Kent

SINCE YOU NOW POST YOU HAVE AN ALTERNATOR

If thats the GM 10 SI self internally regulated family of 3 wire alternators

DO NOT USE THE OLD VOLTAGE REGULATOR WHATSOEVER.

The tractor MUST be used at Negative ground and heres how I describe wiring them.

The big rear main alternator output terminal goes to the wire that used to be connected to the BAT terminal on the Voltage Regulator or Cutout Relay. The alternator output wires to the Load (NOT battery/starter) side of the ammeter. HOWEVER if that wire wasnt already upgraded, when I convert from a Genny to an Alternator, I replace that wire with a 10 Gauge and it runs from the alternators main output up to the LOAD (NOT to battery/starter) side of the ammeter. I also replace/use 10 Gauge from the ammeters other SUPPLY terminal to the battery/starter.

The little side 2F Voltage Sense Terminal gets connected (use a short 14 jumper wire) right up to and with the big main output terminal mentioned above.

For the little 1R side Excitation Terminal, run a 16 or so gauge wire from the ignition switches IGN (which is hot ONLY when ignition is turned on) output terminal or the coils high input (NOT to distributor) terminal, and in series with it place a 10 to 15 ohm 5 watt or so current limiting protection resistor . Then in the rare event the tractor continues to run cuz of alternator backfeed when the ignition is switched OFF, I add in series a 5 amp 50 PIV minimum Diode. The diode must be wired with negative cathode end to the alternator and positive anode end to the switch. Again, the ratings are not that exact but about any diode over a few amps and 50 volts or so works. THE DIODES LIKELY NOT NEEDED IF YOU USE THE 10 TO 15 OHM RESISTOR

Dont forget to change the battery to negative ground and the coil needs to be wired so the negative goes to ground via the distributor points and the positive gets power from the ignition switch and you have to reverse ammeter leads also if you’re just now changing polarities.

Good luck Ol John T in Indiana

If it had a regulator on it and it was working, it needs one. The Delco alternators that need an external regulator have a plug (or connector hole) that faces to the rear of the tractor. A 10SI internally regulated alternator has a plug hole on the top edge of the alternator and the prongs insert radially. I will find a diagram for you. but you need this now. Jim

If it is a 10DN external alt!! Jim