Ford 3000 Battery Not Charging

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All, I replaced the battery on my 1970 Ford 3000 a while back. When I did so, I did not re-polarize (aka 'flash') the field terminal on the regulator. I think that's why my battery is not charging. However, when I went to do this, I noticed the wires go all the way into the regulator. So, the terminals are not exposed. While removing the regulator one of the rubber "spacers" broke off. (Everything under the hood is pretty dirty/worn out.) So, I'm wondering should I just replace the regulator? (I'm thinking that's what I need to do.) And if so, seems like I should also replace the wiring harness...Or should I just cut the existing wires and install quick disconnect junctions that I can plug into the new regulator? Thanks in advance for any assistance.
 

rubber spacers snap on to a slot on the regular, so that is normal.

I would guess the contacts on the vr are dirty or vr is bad,, or the genny is toast,, in that order.

If you put b+ to the field on the gen while running, you should see battery voltage start coming up. assuming you have a volt meter across the battery and a jumper with alligator clips on both ends.

Dont do this test very long as the genny goes to full output and can overheat... If voltage comes up, the generator is usually good.
 
It is actually the generator that gets polarized, but one of the common methods to do so is by using the wires at the regulator. Simply disconnecting the old battery and installing a new battery should not cause the generator to lose its polarity.

The original VR on that tractor had external exposed spade type terminals with connectors on the ends of the wires in the wiring harness that pushed onto the spades. Some replacement VR's have external exposed screw-type terminals, but I've never seen one without external exposed terminals of one kind or the other, so I have to assume that the Voltage Regulator in your tractor is not the original one. Since you do not know what type of VR it has, and if you want to stay with the generator and VR setup, I would purchase a new VR from this site. Then I would trace the wires from the old VR into the harness to see if they've been spliced into the harness as the VR wasn't part of the original wiring harness. You never know, the original spade connectors on the wires might still be there in the harness covered up by a bunch of electrical tape. If not, I would crimp the proper connectors onto the ends of the individual wires to match the terminals on the new VR.
 
6V or 12V? Regardless, your problem has nothing to do with a new battery. Mucked up wiring most likely. Your generator is a "B" Circuit Design so how did you "polarize" it? Shorting/arc-sparking the BAT to ARM terminal is the method used on "A" Circuits and if you did it that way, you probably fried the VR. Why start replacing parts? Best to go thru entire wiring with a continuity meter to verify wiring is all correct. Don't guess. Determine the true root cause problem and fix. Rubber is an insulator. A broken tab/spacer probably shorted out the unit. Can you determine if you have a bare wire shorting out? Get out your I&T FO-20 manual and use wiring diagram as a guide.

POLARIZING GENERATOR CIRCUIT DESIGNS:
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All sketches/PICTOGRAMS courtesy of JMOR



Tim Daley(MI)
 
(quoted from post at 08:05:01 12/15/20) 6V or 12V?
...
Tim Daley(MI)

The 3000 was only ever made with a 12 volt electrical system. Your pictures are for an earlier pre-1965 Ford tractor. The VR on a 3000 has 6 terminals, not 3.
 
Thanks, guys. I would definitely like to confirm there's a bad part before I replace anything. However, I'm a novice when it comes to electrical matters like this...

I read somewhere that all Ford 3000 models were 12-volts from the factory, and it looks like a 12-volt battery in it (it has six vent 'posts')...

So, looking at your diagram, what am I hooking up to what in this picture? I have a multi-meter that I've used occasionally, but mostly when I have specific instructions from YouTube or forums like this. See my comment in first paragraph. :)

Also, I have a Ford 3000 shop manual, but the electrical diagrams are a bit Greek to me. Maybe I just need to do more studying of electrical concepts before proceeding...
 
I'll make it as simple as possible for you. Do this with the engine off. Take the "F" wire off of the generator. Grab a jumper
wire and attach one end to battery positive. Take the other end and scratch the "F" terminal on the generator with it. You
should see a spark as you drag the jumper wire across the post. If you do, that means that the generator has an active field
circuit, and that it is properly polarized. If you don't, that means the field circuit inside the generator is dead, and will
need to come off for repair.

If the generator "F" terminal did show a spark, start the engine, rev to half throttle, and put a voltmeter on the battery.
Attach your jumper wire to the "F" post on the generator. Battery voltage should slowly start to climb. Make sure it climbs
over 13 volts before you pronounce the generator good. If the voltage did rise, then you have a faulty regulator. If the
voltage did not rise, you could still have a faulty regulator, however check the voltage at the "A" terminal of the generator
to make sure you have at least 14+ volts. If you do have voltage at the generator, it's working. If not, you likely have a
faulty generator (bad brushes).

Hope that helps.
 
So, does anyone know why my comments keep getting flagged as 'spam'? I simply added a comment stating "Here's the VR" with an uploaded picture, and I get the following response...

We are sorry, your post contained one or more words that are restricted due to either YT User Community standards or are common indicators of spamming, cracking, or spambot activity.
 
You are a new member, and new members need to post around 10 times or so without other folks flagging them before the site will allow you to post pictures. If you contact the site admins directly they will usually set your ID so you can post pictures sooner.
 
(quoted from post at 10:21:07 12/15/20) I'll make it as simple as possible for you. Do this with the engine off. Take the "F" wire off of the generator. Grab a jumper
wire and attach one end to battery positive. Take the other end and scratch the "F" terminal on the generator with it. You
should see a spark as you drag the jumper wire across the post. If you do, that means that the generator has an active field
circuit, and that it is properly polarized. If you don't, that means the field circuit inside the generator is dead, and will
need to come off for repair.

If the generator "F" terminal did show a spark, start the engine, rev to half throttle, and put a voltmeter on the battery.
Attach your jumper wire to the "F" post on the generator. Battery voltage should slowly start to climb. Make sure it climbs
over 13 volts before you pronounce the generator good. If the voltage did rise, then you have a faulty regulator. If the
voltage did not rise, you could still have a faulty regulator, however check the voltage at the "A" terminal of the generator
to make sure you have at least 14+ volts. If you do have voltage at the generator, it's working. If not, you likely have a
faulty generator (bad brushes).

Hope that helps.

Yes, this helps. I did as you said and scratched the F terminal with a jumper wire. It sparked...

So, then I tried to crank, and (as always) I had to jump it off with my truck. Voltage on the battery was less than 11 volts before I jumped it off. Then, when I disconnected the jumper cables, the voltage was slowly dropping...

I connected the jump wire from the positive post on the battery to the F terminal on the generator. That just caused the voltage meter to start falling more rapidly, which I thought was strange...

How do I check voltage on the A terminal?
 
Either your brushes are bad in the generator (most likely), or else the cutout relay in the regulator is not closing.

To tell the difference, put your voltmeter positive lead on the A terminal of the generator, and the negative lead on the
block or negative terminal of the battery. You should have basically zero volts (or near zero) with the engine running and the
field terminal open. Then attach your jumper wire to the "F" post and watch your voltmeter. If it spikes high, like 14 plus
volts, that's a good sign. If there's little to no change, you likely have worn or sticking brushes inside the generator.
 

Thanks, Bern. I had no voltage from the A terminal with the F terminal open and the engine running, and I got around 20 volts when I jumped the positive post of the battery to the F terminal. So I guess I need a new regulator?
 
That is an original style voltage regulator for a 3000. Those black plastic connectors that the wires disappear into are the covers for the femal side of the spade connectors inside. The black plastic connectors should slide off of the male spade connectors that are part of the voltage regulator.
 
That would be my conclusion. Take the cover off the regulator and check out the cutout relay contacts, see if they're dirty or simply need a little nudge. I bet if you push the contacts down with your finger it would start to charge (with everything else hooked up normally).
cvphoto67076.jpg
 
(quoted from post at 15:59:02 12/15/20) That would be my conclusion. Take the cover off the regulator and check out the cutout relay contacts, see if they're dirty or simply need a little nudge. I bet if you push the contacts down with your finger it would start to charge (with everything else hooked up normally).
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto67076.jpg">

I think I'm just going to replace the VR. Last question...There's two on this site that look like they could work. One is $17 and one is $47. Which one do I need? (I don't see the part number on the old VR.)
 
The amperage rating of the VR needs to match the generator. The $47 VR on this site is an 11 amp VR. The $17 one is a 22 amp VR. I think the higher cost of the 11 amp VR is due to fewer tractors needing them so they don't sell as many. The 11 amp gen & VR was only used in European tractors made before 4/1/68 and the 22 amp was used in European tractors made on and after 4/1/68 and US made tractors of all years. If your tractor is a 1970 model, then it should take the 22 amp VR regardless of where it was made.
 
I'd be very leery of the quality of a $17 VR. That said, don't buy the $47 one either for the reasons Sean mentioned. Just
don't throw out your old one. If the el-cheapo version gives you fits, you could always clean up the points on the old one, or
be done with the misery once and for all and convert your tractor to an alternator.
 
(quoted from post at 09:02:11 12/16/20) I'd be very leery of the quality of a $17 VR. That said, don't buy the $47 one either for the reasons Sean mentioned. Just
don't throw out your old one. If the el-cheapo version gives you fits, you could always clean up the points on the old one, or
be done with the misery once and for all and convert your tractor to an alternator.

Thanks for the tips, Sean and Bern. I'll hang on to the old one just in case, and I'll post back here when I get the new one installed.
 

Just to follow up on this...Got the new regulator installed and all is well now. I actually wound up replacing the battery as well because it wouldn't charge past about 13.5 volts, which wasn't enough to get it to crank. Took it to O'Reilly's and had it tested - bad battery. So now it has a new battery and regulator and running like a champ. On to the next issues...
 

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