6 volt generator issues

grandpa Love

Well-known Member
Working on a C,for a customer,she wants to leave it 6 volt. The generator bench tests good. ...... But ,this sounds crazy, it will only motor with the jumper cables on negative ground,it will not bench test "motor" with positive ground. (On one generator ,the other one runs no matter how it's hooked up to the battery) No matter what we do it will not show a charge when the belt is on a tractor running. With the voltage regulator hooked up or unhooked. All new wiring,done correctly. New battery and big cables. All grounds on generator and voltage regulator are clean!!. Polarized ,saw the spark. Several times. Any advice?? Tried 2 different generators.🤔. Both have been opened up ,cleaned and the 3rd brush removed and the wire moved to the correct spot. We could have dropped an alternator on this 8 hours ago and been done with it.
 

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Working on a C,for a customer,she wants to leave it 6 volt. The generator bench tests good. ...... But ,this sounds crazy, it will only motor with the jumper cables on negative ground,it will not bench test "motor" with positive ground. (On one generator ,the other one runs no matter how it's hooked up to the battery) No matter what we do it will not show a charge when the belt is on a tractor running. With the voltage regulator hooked up or unhooked. All new wiring,done correctly. New battery and big cables. All grounds on generator and voltage regulator are clean!!. Polarized ,saw the spark. Several times. Any advice?? Tried 2 different generators.🤔. Both have been opened up ,cleaned and the 3rd brush removed and the wire moved to the correct spot. We could have dropped an alternator on this 8 hours ago and been done with it.
Did the FB’ers give you the poo-poo on this? What does it do when you ground the field terminal when it is running? That removes the VR and cutout from the picture and tells you if the genny is able to do its thing or not. I am no expert on these, would have to do some studying to get you beyond that. I for certain don’t know what goes on when you remove the 3rd brush.
Here is JohnT’s Charging Troubleshooting run down. It seems a little over done but what else would one expect out of a lawyer. I guess it has helped out some folks.
JohnT charging troubleshooting
 
Did the FB’ers give you the poo-poo on this? What does it do when you ground the field terminal when it is running? That removes the VR and cutout from the picture and tells you if the genny is able to do its thing or not. I am no expert on these, would have to do some studying to get you beyond that. I for certain don’t know what goes on when you remove the 3rd brush.
Here is JohnT’s Charging Troubleshooting run down. It seems a little over done but what else would one expect out of a lawyer. I guess it has helped out some folks.
JohnT charging troubleshooting
I was hoping some kind soul here would know what was going on and offer advice.
 
I was hoping some kind soul here would know what was going on and offer advice.
I’m kind…. but just a little snappy sometimes! :) Did you run it with the field terminal on the genny grounded? Or is that in the “everybody knows that category” so it’s not considered “advice”? Is the ammeter working showing a discharge with the ignition or lights? Or are you reading battery voltage with a meter?
 
Sorry, no help here. First one we switched to 12 v was doing basically same thing. Took it to a very well known shop twice. Would work sporadically. Finally gave up and went to alternator.
 
Who's gonna pay for that? 😉 Were you gonna find that shop?? 😜
Thought u had a cub shop on your place . So get someone to come in and check the fields and armature for continuity and shorts and I guess you will have to pay him. Maybe ur Mrs Will do it and give u a deal. Show us with pictures exactly how u are motoring these 2. Plus a working generator will produce power just by spinning it with a wire wheel
 
It looks like you tried two different generators and neither one will charge. One of those will motor in both directions and one only goes one way. Did you use the same voltage regulator for both generators ?

I'm trying to imagine why a DC motor wouldn't run in both directions. It shouldn't matter how the field windings are polarized. Even if they are 'wrong', it should run both ways. Does it lock up when it won't run ?
 
What happens if you hold both [field & cut out] contacts on the reg.
closed? It should charge when you do this.
Did you put new brushes in this unit? Are they contacting the
commutator flat? I had one that had a brush that didn't lay flat
on the commutator & the brush holder was bent. I'm assuming
you have checked continuity on the fields even since it motors
on 1 polarity?
Jim
 
I’m kind…. but just a little snappy sometimes! :) Did you run it with the field terminal on the genny grounded? Or is that in the “everybody knows that category” so it’s not considered “advice”? Is the ammeter working showing a discharge with the ignition or lights? Or are you reading battery voltage with a meter?
Yes to all the questions...very frustrating 😔
 
It looks like you tried two different generators and neither one will charge. One of those will motor in both directions and one only goes one way. Did you use the same voltage regulator for both generators ?

I'm trying to imagine why a DC motor wouldn't run in both directions. It shouldn't matter how the field windings are polarized. Even if they are 'wrong', it should run both ways. Does it lock up when it won't run ?
The one that only runs with the battery hooked up negative ground is the real puzzle 😮. Never seen anything like it.
 
Thought u had a cub shop on your place . So get someone to come in and check the fields and armature for continuity and shorts and I guess you will have to pay him. Maybe ur Mrs Will do it and give u a deal. Show us with pictures exactly how u are motoring these 2. Plus a working generator will produce power just by spinning it with a wire wheel
Hey, Rust......my wife has opened up both generators. Tested for continuity and checked for shorts. Brushes look good,and sit correctly. Keep in mind she works on a bunch of starters and generators every month. She has a high success rate at getting non workers working 😁. Of course the site won't upload a 6 second video showing a bench test. ....will slap it on YouTube and then post it
 
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