53 JD 50 Voltage Regulator - 3 wire or 4 wire?

I have a 53 John Deere 50 with a 1100955 generator. The current voltage regular is a 3 wire and when looking on YT's web site, it says this generator calls for a 4 wire. The shop manual states it should be a 1118306 regulator and the photo shows 3 wire. My question is, do replace it with a 3 wire or do I get the VR1816 regular which is listed as a 4 wire and what do I do with that 4th terminal?

I bought this tractor not running so I cannot confirm when it was last running and charging correctly.

Thanks,

Link

EITHER a 3 or 4 terminal will work. If its a 4 wire with the extra 4th LOAD terminal, L feeds loads like lights and ignition power to the BAT input terminal on the switch. If its a 3 wire with no LOAD terminal, those loads feed instead from the Load (NOT Battery/Starter) side of the ammeter wired to the BAT input terminal on the switch. Id use whichever VR it came with original from the factory, even though either can be wired as above and made to work.

John T

The shop manual suggests it was a 4 wire part # but the photo shows only 3? Perhaps I replace it with the 3 terminal model since that is what it has currently? One terminal goes to the generator, the other two go from ampmeter and to the switch. This tractor was not wired so when I rewired it, the ampmeter was showing a high draw even with the switch off so I think the voltage regulator was shorted.

I have a late B that takes a four wire regulator. I have two wires coming from the dash. One goes to the battery and one to the ignition. on the regulator, one wire goes to battery terminal, and one wire goes to the lights terminal. Hopes this helps. PS. the forth terminal is hid underneath the regulator. john

When you say "but the photo shows only 3?" Do you realize one terminal (often ARM) is hidden underneath the VR???

John T

I may need to double check that now. That wire would go to the generator directly, right?

"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]That wire would go to the generator directly, right?[/i:654c4848f0][/b:654c4848f0]</font>"

Yes, [i:654c4848f0]that wire would go to the generator directly[/i:654c4848f0].

Take a look at the photos below of a 4 terminal voltage regulator on our 52A.





Note that the armature terminal underneath the voltage regulator is connected to the [b:654c4848f0]A[/b:654c4848f0] armature post/terminal on the generator.

Note the [b:654c4848f0]FLD[/b:654c4848f0] terminal on the voltage regulator is connected to the [b:654c4848f0]F[/b:654c4848f0] field post/terminal on the generator.

Note the [b:654c4848f0]BAT[/b:654c4848f0] terminal on the voltage regulator is connected to the NEGATIVE - post/terminal on the ammeter.

Take a look at the diagram below.



Note that the [b:654c4848f0]L[/b:654c4848f0] terminal is connected to the light switch on the dash of our 52A.

Since the ignition switch on your Model 50 has a terminal for the lights, this [b:654c4848f0]L[/b:654c4848f0] terminal will not be connected/used on your Model 50.

Take a look at the diagram below.



Hope this helps.

This helps a lot. Thank you. It looks like I have a generator that wants a 4 terminal regulator but currently has a 3 terminal version on it.[/img]

So just to be clear, why would I not run a wire from the L terminal to the ignition switch, would I just connect that directly to the battery?

On a 4 wire VR the L (Load) terminal feeds hot battery voltage to loads (lights and ignition) so L on VR wires to the BAT (Input) terminal on the light and ignition switch. Lights and Ignition would still work if the light switches BAT input terminal connected direct to the battery, but then the VR isnt doing the same job of monitoring and regulating as well as if loads actually passed through it.

BAT on the VR (3 or 4 terminal) is what wires to the battery so the generators output can get connected to (when cutout relay closed) and charge the battery.

Got it??

John T

I think so. I'll get a new regulator and use this thread to make sure I get it hooked up correctly!

Thanks for all the help.

I own a '51 B that had a factory original 4 terminal regulator and wiring harness. Previous owner apparently replaced the regulator with a new 4 poster but did so incorrectly. Both the light feed and the battery wires were connected to the BAT terminal leaving the L post not used. I changed this and found that it certainly does make a difference!

With both wires on the BAT terminal when the lights were on, the speed control had to be within an inch of full speed or the ammeter indicated a discharge. When I corrected the wiring making the L terminal feed the lights, it allowed the engine speed to be variable to almost a dead idle before the ammeter showed any discharge. Same lights, same generator, same regulator, same battery, same tractor.

My 70D did not have this arrangement. I added the lights feed wire and changed the regulator to a 4 poster. Have never regretted it.

The generator really doesn't care. It's all a regulator design that allows better control of the field current needed for the high current demands of lighting operation as opposed to just re-charging the battery!

Hope that helps.