More on regulator conversion

A few weeks back I tested the waters here regarding replacing the stock cut out on the generator of my 1949 C with a regulator and, based on the feedback, I opted to do that. I had a very reputable local auto-electric outfit (that's been around longer than me) rebuild the generator and install the correct regulator. Now for the confusion. A bigger aftermarket tractor supply I've been doing business with sells a "cut out to regulator conversion kit", which amounts to a resistor mounted on the F terminal of the regulator that leads to the F terminal of the generator. The remaining instructions are to run a line from the GEN terminal on the regulator to the A terminal on the generator. The L terminal on the regulator goes to the BAT hook up on the light switch, and the BAT terminal on the regulator goes to the ammeter. The stock following are discarded; F line off generator to the feild resisitor on the light switch and the lead that (originating at the BAT lead on the cut out) from the ammeter to the light switch. (God bless all you guys that can follow that.) Anyway, my auto electric guy says the resistor kit is unnecessary and to just hook the old wires as was to the BAT & L terminals on the regulator. Thinking the tractor outfit has more experience in these types of applications, I bought the kit. Question is, is this resistor indeed necessary and why, and is the remaining wiring as I've described ok? Before I apply the juice, I really would love to hear from you in the know. Thanks for your help.

Your local guy was correct. in parts and so was some of the wiring described in the KIT.
The L terminal hooks to the light switch input using #19ga wire (probably the fues holder, not the old field control terminal, it gets abandoned, as does its smallish wire to the F terminal of the GEN).
Next a #10 ga wire is hooked from the Bat terminal of the new VR to the Amp gauge. (on the side of the amp gauge not connected to the starter switch)
Next a #10ga wire connects the Gen terminal of the VR with the A terminal of the Gen.
Next the F terminal of the VR is connected to the F terminal of the Gen. Absolutely no resistor in that wire.
A #12 wire is fine for that field control.
Both the gen and regulator must be cleanly grounded to assure operation.
Go for it. Jim

Jim; That 19 gauge is pretty light. Did you make a typo?

If I said 19 it was a typo. Gen to Arm 10 ga. bat to Amp gauge 10 ga. L to Light sw. 10 ga. Field to F on gen 12 ga. Jim

The fellow who builds those regulators had an article about them in RED POWER some time ago. i forget the Delco Remy gen# that kit is for it was for the gen with third brush and the 4 position lite sw. I have used them and wired that way and they work. The reg part # is a vr 1429 if i remember and i just looked it up its to be useed for gens#1101355 and 1101423 gens #1101501 and 1101531 use the other reg its # is13911 and it works on the H series Ms MTA TILL THEY WENT TO 12V SYSTEMS. Now if your gen isnt original and the tag is missing you can have a problem as the subject is on this subject all the time. I keep mine original and have no problems.

Jim, whenever I post I hope you are among the responders. I very much appreciate all the help you've given (as I do everyone's here on the forum). You are indispensible to my efforts. I'm sure a lot of the newbies and under-educated Farmall crew feel the same. Thanks again.

Jim, one last thing. You are pretty specific about omiting the resisitor that comes with the kit from F on the reg to F on the gen. That basically was "the kit". What's the rationale behind it? Gene seems to indicate it has something to do with the 4 position light switch. I assume I'm just going to have 2 off positions now. Any insight on the purpose of this resistor. Curious, since I forked out $35 for it. Thanks.

The field is supplied voltage internally in the generator. The F terminal on the gen is grounded externally to make the field have current flow.
If the F terminal is grounded with a jumper directly to ground, the gen puts out maximum power.
If the Field is connected to a regulator, the field is at first fully grounded through the field contacts inside the VR. As soon as the voltage is high enough to charge the battery correctly, the points begin to vibrate, opening and closing rapidly to control the field current, which controls the output.
There are built in resistors which allow the level of current flow to be based on outside temperature, and not go fully to zero output.
These resistors are on the bottom of the regulator exposed to external air.
A properly designed regulator has no need for a added resistor. Putting one in the connection to the gen F terminal would be reducing the output of the gen, and not good engineering or practice.
The light switch will be a light switch from now on. It was used to control the gen output by being full ground output to the light switch body and the electrical box connection to the tractor ground. (when the control knob was in H, D or B positions.) this full ground charged the battery at full gen output when the lights were on, and or when the operator knew the tractor would be started and stopped often requiring more charge.
In the L position the operator chooses to charge at a low rate to just maintain the battery while doing day time field work.
The L position uses a resistor (on the control switch) to reduce charge rate.
A regulator removes this operator responsibility from the playing field.
Jim