Ford 8N charging system

1952 Ford 8N Type A charging system. The generator has 3 terminals GND, Field and Armature. Why the GND terminal when the generator is grounded by its mounting. Does the regulator frame need to be insulated from the tractor ground? It is 6V pos ground and is not charging.

(quoted from post at 19:48:34 05/04/23) 1952 Ford 8N Type A charging system. The generator has 3 terminals GND, Field and Armature. Why the GND terminal when the generator is grounded by its mounting. Does the regulator frame need to be insulated from the tractor ground? It is 6V pos ground and is not charging.

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There's nothing wrong/unusual with the redundant ground between the generator and VR ''frame'', just makes for more accurate voltage regulation.

HiYa Ted-
Welcome aboard but know that there is a separate forum for the FORD N-SERIES Models where you'd get many more replies. I'll let the electrical gurus like JMOR, SOUNDGUY, or Bruce (VA) Haynes answer you question about the GROUND connections. By a '52 8N you will have the later Angle (SIDE) Mount Distributor. That and if 6V/POS GRN or 12V/NEG GRN are the important factors, serial numbers/model year guesses, mean relatively nothing as blocks and parts were swapped out a lot. Let's start over. You have an 8N with the side mount distributor, right? You have a 6V battery but that doesn't mean the system is wired correctly for a 6V/POS GRN setup. You say it is not charging but does the tractor start and run otherwise? What does the AMMETER show at idle? Do you have a fan belt tensioning bracket attached? Whether if using a GEN or ALT, if you do not have belt tensioning device to maintain proper fan belt tension, you will never charge the battery. Period. Have you had the battery tested at a shop? If tractor is left in the barn at rest for over a week the battery will rapidly decay and lose specific gravity. Simply connecting basic garage trickle charger will not do anything if the battery is weak or dead. Get it tested under load at a reliable shop, usually at no charge, pun intended ; > ). Next, have you verified the entire wiring system? Use your manuals and documents as your roadmap. Use your VOM set to CONTINUIY and never an idiot test light for this procedure. Idiot Lamps require power and you don't want power when tracing wiring, and I advise to disconnect the battery altogether for this. I also advise to disconnect any light circuits for now. Lighting kits were never a factory installed feature on FORD TRACTORS until the 800 Series. Dealers supplied lighting kits and would install or you could do it yourself but many were/are wired incorrectly, 12V is often a culprit. Also, do not use the OEM Wire Color Codes colors dont conduct electrons. Your wiring harness probably isnt original anyway, and all new aftermarket ones made today are not color coded correct as well unless made as an exact-as-original harness. Next, I assume you mean your GEN is an A Circuit Design. ALL 8N's and 9N & 2Ns except for the first early 9N GEN, use an A Circuit GEN. The early 9N small barrel 7-AMP, 2-Wire/2-Brush, unit used the B Circuit Design. Beginning with the NAA in 52, all FORD Tractors used the B Circuit again. Use Caution when Polarizing with your VR. Do it wring and you fry the VR. The GEN must be polarized as either POS or NEG, whatever system you will use, done when wired and tested but you can polarize the GEN with your Voltage Regulator. With a 12V system, you remove the GEN and VR from the circuit and there is NO Polarizing involved. The entire wiring must be correct. That means: a 3-Wire/2-Brush 20 AMP A Circuit GEN, a 3-Wire Terminal (ARM BAT FLD) ; a Starter Motor with a 3-Wire RELAY (Solenoid); Safety Start Pushbutton; an AMMETER; and Ignition Lock/Key Switch. Good correct battery cables are required. Having the distributor tuned and timed correctly via inspection cover and flywheel timing hash marks with a timing light are the final operation. Firing Order is 1,2,4,3 CCW. Points gapped at .025 Plugs gapped at .025. Use the OEM style flat-braided ground strap. Forget lights until all is right with the wiring.

*NOTE: 8N WIRING PICTOGRAM by JMOR


POLARIZING THE GEN VIA THE VR:


Tim Daley (MI)