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6 Volt Generator Charging Problem

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Old Mar 21, 2026 | 10:45 PM
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6 Volt Generator Charging Problem

Can anyone recommend a source for a new 6-volt generator that actually works or an experienced shop that can repair our generator? We have replaced/checked the regulator, checked the wiring (all new) with a meter, properly polarized the generator and have had so called "experts" attempt to repair It. The problem is it does not charge. Are we missing something?

Thanks
 
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Old Mar 21, 2026 | 10:58 PM
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Which generator do you have? The 36 Amp C8BA, the 40 Amp 8EL, the 60 Amp 8BA? Do you have the matching regulator the C51A-C, the 8BA, the C8BAS?

You do know that the AMP gauge will not show a charge indication if the battery is actually charged?
 
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Old Mar 21, 2026 | 11:05 PM
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Where in the world are you?
 
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Old Mar 21, 2026 | 11:16 PM
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OP is in Owatonna, Minnesota. Probably would need to go an hour or so north towards Minneapolis/St. Paul and go to a place like Auto Electric Service, 11920 Riverwood Dr, Burnsville, MN 55337 for services.

If one does take their unit to be serviced, the regulator should also accompany it to be tuned accordingly.
 

Last edited by bmoran4; Mar 21, 2026 at 11:18 PM.
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Old Mar 22, 2026 | 06:08 PM
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I've been through hell and back with 6v generators. My savior is Steve Blancard. Can't thank him enough. He does this work for the love of it, rare to see it. He's at Hersey every year too it seems. But his email is ....splitdorf@***.net

You will thank me! He restores Early Ford 6V Generators to stock condition.
 
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Old Mar 22, 2026 | 06:53 PM
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Originally Posted by 100550dvr
Can anyone recommend a source for a new 6-volt generator that actually works or an experienced shop that can repair our generator? We have replaced/checked the regulator, checked the wiring (all new) with a meter, properly polarized the generator and have had so called "experts" attempt to repair It. The problem is it does not charge. Are we missing something?

Thanks
You probably have checked a lot of things, so sorry if I am taking you down the same path.

1. You mentioned polarizing the generator. Make sure your Generator is wired correctly to the Voltage regulator. Gen Field to Volts Regulator Field, Gen Armature to Volts Reg Armature. Also you have a ground wire connected between the Voltage Regulator base and the Generator ground terminal. Next with the battery connected go to the Volts Regulator and carefully remove the Battery and Field wires and touch them together. Do you get a small spark? If so good. If not further investigate the wiring conditions and connections to your Generator.

2. Assuming you are done with step 1, reconnect the Battery wire to the Voltage Regulator but leave the Field wire off just for now. Start the truck, measure the voltage at the battery. Hopefully your battery has been charged, but lets see if the Generator will charge by measuring the voltage while you are full fielding the generator. With the truck running short the FIeld wire to the Battery Terminal connection on the Voltage Regulator and watch the battery voltage. It should slowly start to rise. If not have someone Rev up the engine to what you think could be over 1500 RPM. Why do this? Your voltage regulator cut out relay may need more current to pull in, thus connecting the Generator to Battery for charging. Some folks (including me!) have forgot the "give her more RPM part" and thought they still had a bad Regulator or Generator.
If the Generator appears charging now, normal everything back together and drive.
IF you want to, you could make a GEN failure light like we used to have in our dash. Just take a 6 volt light, a socket, and splice in a couple of lengths of wire. One to a 6 volt switched terminal to your Ignition switch, the other connects to the Armature terminal on your voltage regulator. You start up the truck the light will be on until you rev the engine or pull out of your driveway and shift. When the light goes out it means your battery and generator are now connected by your Voltage Regulator. If you are sitting at a traffic light and you see it flicker, don't worry, at a low RPM idle it may do that.





 

Last edited by hooler1; Mar 22, 2026 at 06:56 PM.
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Old Mar 23, 2026 | 03:24 PM
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bump
 

Last edited by Lando25; Mar 23, 2026 at 03:26 PM.
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Old Mar 23, 2026 | 03:27 PM
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Originally Posted by bmoran4
OP is in Owatonna, Minnesota. Probably would need to go an hour or so north towards Minneapolis/St. Paul and go to a place like Auto Electric Service, 11920 Riverwood Dr, Burnsville, MN 55337 for services.

If one does take their unit to be serviced, the regulator should also accompany it to be tuned accordingly.
Im actually OP's son. I took the generator and regulator to a reputable shop and they supposedly checked everything out and tuned the regulator circuits as required. I reinstalled everything, flashed the generator, verified the wiring and she still wont charge. I went as far to do a motoring test with a charged battery and it barely spun so I'm still leaning towards a bad generator.
 
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Old Mar 23, 2026 | 03:54 PM
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Here is some documentation on testing generators - Ford used Type "B":

https://www.delcoremyhistory.com/ima...rators%204.pdf

I would also not be afraid to contact the shop and ask their advice - if they are reputable, they should stand by their work.
 
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Old Mar 24, 2026 | 05:42 AM
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Old Mar 24, 2026 | 11:05 AM
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Originally Posted by hooler1
You probably have checked a lot of things, so sorry if I am taking you down the same path.

1. You mentioned polarizing the generator. Make sure your Generator is wired correctly to the Voltage regulator. Gen Field to Volts Regulator Field, Gen Armature to Volts Reg Armature. Also you have a ground wire connected between the Voltage Regulator base and the Generator ground terminal. Next with the battery connected go to the Volts Regulator and carefully remove the Battery and Field wires and touch them together. Do you get a small spark? If so good. If not further investigate the wiring conditions and connections to your Generator.

2. Assuming you are done with step 1, reconnect the Battery wire to the Voltage Regulator but leave the Field wire off just for now. Start the truck, measure the voltage at the battery. Hopefully your battery has been charged, but lets see if the Generator will charge by measuring the voltage while you are full fielding the generator. With the truck running short the FIeld wire to the Battery Terminal connection on the Voltage Regulator and watch the battery voltage. It should slowly start to rise. If not have someone Rev up the engine to what you think could be over 1500 RPM. Why do this? Your voltage regulator cut out relay may need more current to pull in, thus connecting the Generator to Battery for charging. Some folks (including me!) have forgot the "give her more RPM part" and thought they still had a bad Regulator or Generator.
If the Generator appears charging now, normal everything back together and drive.
IF you want to, you could make a GEN failure light like we used to have in our dash. Just take a 6 volt light, a socket, and splice in a couple of lengths of wire. One to a 6 volt switched terminal to your Ignition switch, the other connects to the Armature terminal on your voltage regulator. You start up the truck the light will be on until you rev the engine or pull out of your driveway and shift. When the light goes out it means your battery and generator are now connected by your Voltage Regulator. If you are sitting at a traffic light and you see it flicker, don't worry, at a low RPM idle it may do that.

Thanks for the reply. I did verify the gen to regulator wiring was correct and properly grounded. I removed the field wire from the regulator and started her up. I did not notice any change in battery voltage (around 6.3). I wasn't until I shorted the field wire to the battery wire that the voltage jumped up to 8 volts.
 
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Old Mar 24, 2026 | 12:44 PM
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I gave up and went with an alternator. I have a 239 Y-Block.
Amazon Amazon

Not cheap but easy to wire up and solved my charging problems. I went through a couple of generators and I don't know how many voltage regulators before I gave up.
 
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Old Mar 24, 2026 | 01:44 PM
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Originally Posted by Lando25
Thanks for the reply. I did verify the gen to regulator wiring was correct and properly grounded. I removed the field wire from the regulator and started her up. I did not notice any change in battery voltage (around 6.3). I wasn't until I shorted the field wire to the battery wire that the voltage jumped up to 8 volts.
So when you shorted the Field wire to the battery wire you got 8 volts? Sounds like you just proved your Voltage Regulator could be the culprit. Before condemning it completely after reconnecting everything, did you give it some good revs and look at your battery voltage again?
 
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Old Mar 24, 2026 | 01:47 PM
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I read it as they polarized the generator per type "B" instructions and then all was good:

 
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Old Mar 24, 2026 | 02:36 PM
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Originally Posted by bmoran4
I read it as they polarized the generator per type "B" instructions and then all was good:

Thanks Brian!
My reading comprehension could be failing me.
Maybe the OP could clarify that his charging system is now working as it should.



 
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