Polarizing questions

Seeking clarifications on polarizing a generator:

On my 8N (front mount, 6v positive ground, electronic ignition), just got it started again after a few years of neglect. However, only motored at a low-to-moderate speed and unevenly: could not idle down well, nor run up speed much. Per the I&T FO-4 Shop Manual, a possibility could be the generator needing service and/or repolarizing. Will get back to this in a moment--I read this of course after some fiddling.

In my fiddling, I observed that when turning on the ignition the ammeter would tick to and hold a very slight ‘positive’ (to the right) deflection. When got the motor to run, I was surprised to see the ammeter holding pretty much at same or zero. Thinking this might be due to lost polarization, I proceeded to investigate. While it was running I tried to measure any voltage coming off the generator with an electronic voltmeter. Checked across every terminal (generator field, generator armature, generator ground) as well as each to engine block… Also tried to read if any amps same way. No meaningful readings in any way, but when looked back at ammeter, saw it was reading negative 30 amps! At that I shut it down for the night and decided needed to do some researching. After some basic reading, remaining questions and possibly conflicting information has led me to the distinguished company within this august forum.

My review of the Shop Manual, specifically Paragraphs 72 and 79, suggest that, in addition to some TLC or even overhaul for the generator, it probably required polarizing, which I may have accomplished in my fiddling. Or maybe reverse-polarized.
Paragraph 72 “Generator Motorizing Test” suggests polarizing via the following procedure: “Polarize field poles by momentarily contacting generator field terminal with battery lead, to eliminate possibility that field polarity was reversed during test.”
Paragraph 79 “Polarizing Generator” suggests two other methods: “…before it is operated, it should be polarized in order to establish correct polarity with respect to the battery it is to charge. First make all connections between the battery and generator. To polarize a generator where only a cutout relay is used in the system, use a jumper lead to make a momentary connection between the battery terminal or cutout relay or battery terminal of starter switch and the A (armature) terminal of the generator. When a vibrating eternal regulator is used in the system, make a momentary connection between “BAT terminal and “GEN” terminal of regulator. This allows a momentary flow of current through the generator which will establish correct polarity.”

So three potential methods, each leaving me with questions:
1/ Field terminal to battery lead method. I assume the “battery lead” is the hot (not ground) lead, which in my case, the negative (anode) battery terminal. Please correct me if that is incorrect. Can this or should this be done while running; or engine stopped, ignition on; or engine off, ignition off?
2/ Cutout relay Armature method. Why not use the same field terminal to battery lead method? The generator has been operated—will this still work? I don’t believe this is my system (I have same setup, with external regulator, as in Fig. FO71.
3/ Regulator BAT to GEN terminal method. I believe this is same as my setup, though I have never realized (or heard) that it is a “vibrating external regulator.” Is that right? How exciting! The generator has been operated—will this still work? Can this method also be done while operating?

More questions:
How can I test to see if the polarity is correct?
Could my ammeter be wired backward (it is a replacement, perhaps different for positive vs. negative ground? I wonder this as it showed a slight positive “charge” every time the ignition was turned on, before starting.
The high reading on the ammeter suggests dirty commutators and/or other issues with the generator…or is that because the polarity is wrong and is wreaking havoc with amp draw on the battery?
If it is possible to test or correct polarity before starting again, which method is best/should be used?

Appreciate any and all suggestions and wisdoms!

p.s. currently perusing Bruce Haynes “75 Tips for Ford N Owners” http://www.yesterdaystractors.com/articles/artint268.htm

Do not apply battery power to the field terminal. That will burn VR contacts! BATT to ARM jumper is correct method for your 8Ntractor/generator. Use a headlight bulb or some other load to see if ammeter deflects to discharge. If it deflects to charge with a load, it is wired backwards and terminal leads need reversing.

Thank you JMOR. I will try that light test now.

And found this from 75 tips:

23. If you ever do any work on the charging system on your N, (remove the battery, disconnect the generator, etc.), you should re-polarize the generator just in case the generator loses its residual magnetism when the battery is removed from the circuit. Unless you have a very early (and rare) 9N with a B circuit generator and voltage regulator, with the engine off, use a set of metal pliers to momentarily jump across the cutout; when it sparks, it is polarized. [b:cd0bd6deeb]On the 8N, use a flat-blade screwdriver to momentarily touch the BAT and ARM terminals on the voltage regulator, again with the engine off.[/b:cd0bd6deeb] If you have the rare B circuit 9N, polarize it BAT to FLD, just like the NAA.

A light I used didn't draw enough to tell, but no biggie. can check once run again. But first, I need to repolarize with the BAT and GEN terminals on the regulator.

But which ones are they? Three of the four go to the generator...
Which one is GEN?
Is the connection to the terminal block the BAT?

Per the Fig. FO71 linked in above post, I have the same regulator with the following:
one on top marked 'F' going to the generator Field terminal,
one on top marked 'A' going to generator Armature terminal),
one on the side marked 'T' going to the terminal block,
one on bottom marked 'G' going to generator Ground terminal.

In general, is the terminal block the "BAT" and the hot (not ground) side considered the "BAT"?

Is it the generator ground terminal and the 'T' terminals on the regulator I need to make a momentary connection to correctly repolarize?

Thanks - I think I've got it, but might as well try and make sure. Can't find any clear references to confirm the naming.

Hmm.. is the Armature terminal the "GEN" terminal?

As found at MyFordTractors:
1-The large screw terminal located on the end of the generator is the main generator output that charges the battery. It should have a large wire (Yellow with Black stripe) that goes directly to the terminal on your voltage regulator marked "ARM" or "GEN".

2-There should be a terminal on the regulator marked "BAT". This should also have a large wire (Yellow) that goes to one post of the terminal block. On the early, 3-post terminal blocks with a resistor, use the bottom terminal. On the 2-terminal type, without a resistor, pick either one.

What is the "T"? Where is that in FO43? BATT is on the side (#6) and arm is #5.

'T' was my old sharpie mark indicating the wire to the terminal block (probably when I installed new harness a few years ago). on FO43 (I keep calling it FO71 because in my FO-4 manual it is same diagram, different number) on FO43 it is wire 6 running from the side of the voltage regulator to the terminal block.

Great - #6 is the BAT for the purposes of the polarizing.

You called out #5 as the armature terminal. Yes, same for me.

Is this #5 Armature terminal the one to use as GEN in the instructions to connect GEN and BAT?

(If my regulator had Bat and Gen and other indications stamped into them, not visible to me at this time. )

(quoted from post at 21:57:11 07/28/15) Great - #6 is the BAT for the purposes of the polarizing.

You called out #5 as the armature terminal. Yes, same for me.

Is this #5 Armature terminal the one to use as GEN in the instructions to connect GEN and BAT?

(If my regulator had Bat and Gen and other indications stamped into them, not visible to me at this time. )

Click to expand...

es, GEN=ARM

Thank you!