farmall cub voltage regulator / cut out

I have an early cub that has a cut out on top of the generator. It has 3 wires that go to it. The replacment regulator/cut out I got has the same mounting but has 4 terminals on it. If I'm correct I think what was on it was a cut out and what I got is a regulator. Does one work in place of the other?
Thanks
Greg

A "cutout" will only have 2 terminals.

A typical "voltage regulator" has 3.

Some voltage regulators have a 4TH terminal labelled "L" to power electrical loads such as lights right from the VR/generator.

If your old regulator had only 3 terminals, and the new unit has a terminal labeled "L", simply ignore the"L" terminal and connect up the other three as they were on your old unit.

The cut-out for your Cub had three terminals Field,Armature or mite have been labeled Gen. The other terminal was marked Batt. Your new reg with the 4 terminals should be marked Batt,Field,Gen and L for the lights. Werent there any any instructions with the new one? Does it have a coil for the Field terminal. And is it marked Pos gnd.

Yes it is positive ground and yes it has a field coil.

Greg, regardless if you have a 3 terminal (BAT ARM FLD) or a 4 terminal (BAT ARM FLD LOAD) EITHER can still be made to work...See below

I believe (BUT Im NOT an IHC man like Bob M or janicholson mind you) a few older Cutout Relays that usually had but two terminals (BAT and GEN) also had an F terminal to provide a ground for the gennys Field windings if there was no light switch HOWEVER most and later Cutout Relays had only the BAT and GEN terminals and the light switch regulated the genny by dead grounding the Field for HIGH charge but grounding it via a small resistance for LOW charge.

OKAY heres how to wire that 4 terminal VR

BAT wires to the Load (NOT battery/starter) side of the ammeter.....that circuit is always hot

GEN/ARM is often off on one side or the bottom all by itslef,,,,,,it wires to the gennys ARM post

FLD on the VR wires to the gennys FLD post

L or LOAD is used to feed hot battery voltage up to loads like lights n ignition via a wire to the switches BAT input terminal

NOWWWWWW on the 3 terminal VR's that didnt have that extra 4th LOAD terminal, voltage to feed lights n ignition was fed off the ammeters load (NOT to battery/starter) terminal

SOOOOOOOO you can feed voltage to your lights EITHER by leaving it where it is and IGNORE N NOT USE THE VR'S L TERMINAL ORRRRRRRRR removing the present hot wire from the ammeter over to the switches BAT input and instead run the lights from the VR's L terminal...

It would be easier to leave the light switch feed on the ammeter n not use the VR's 4th L terminal but if you wanna utilize that VR to its full extent re route loads to its L terminal instead of the ammeter

Hope this helps, let me know

John T

John T you are rite you are not an I-H man their cut-outs had three terminals Gen,Field and Batt

Greg:

(quoted from post at 17:25:44 02/15/09) I have an early cub that has a cut out on top of the generator. It has 3 wires that go to it. The replacment regulator/cut out I got has the same mounting but has 4 terminals on it. If I'm correct I think what was on it was a cut out and what I got is a regulator. Does one work in place of the other?
Thanks
Greg

Click to expand...

The TC-37 Parts Catalogs especially the TC-37A, shows the breakdown of the early Cut-outs and the replacements are available still.

Click the GSS-1012 Electrical Equipment link for the Service Manual. You can also check out the GSS-1411 Service Manual for Cubs and Cub Lo-Boy's and then you can also peruse the GSS-1310 Electrical Manual which can guide you through the fundamentals of electrical circuits especially as they pertain to tractors both 6v and 12v.

I hope that helps. This way you get it from the horse's mouth as they say -- since they are IH Service Manuals.

I agree, the old cutouts had that extra FLD terminal (i.e. 3 terminals) in cases where there were no light switches. The later cutouts that used the light switch didnt need any F terminal cuz the gennys FLD post wired up to the switch.

Good post and fun discussion

God Bless n Yall take care now

John T

The IH tractors, right up until they changed to using voltage regulators, had a field terminal on the cut-out. It was typically unused if the tractor had lights.

No the later cut-outs didnt change. They did make a change when they went to a reg. Even changed the position where it mounted.