Generator still won't charge!

Been messing with the generator on the M JD again. Had it rebuilt by a guy and he replaced everything, machine shows it is working. On the tractor it will not do anything. Checked with multimeter voltage never rises.

I rewired whole tractor last fall going by factory diagram used original colors and everything. Just for the heck of it I checked all wires this past weekend and cleaned all connections to bare shiny metal again.

I have tried two different solid state cutout relays with no change. Ran a jumper wire from field to ground with no change. Cleaned connections numerous times, checked belt to make sure it was tight. Checked that ammeter works correctly. Put on a brand new 6volt battery and had it tested to make sure it was good.

Went through everything on JohnT"s tips.

I made sure I polarized it correctly and still not charging at all.
I tried the "motor" test on the bench with jumper cables with a 6v battery wouldnt do anything.
Used a 12v battery and it spun. Wired it just like it would be on tractor. With a jumper to ground on field. Removed the jumper wire and it spun faster. But here is where I get confused. When I removed the jumper wire the generator stopped spining for a split second and started turning the opposite direction. Is it supposed to do that? This thing is causing me alot of grief. Any help is appreciated. Thanks.
 
It does not charge when running but the generator guy says it's a good generator. OK.... You have an open circuit someplace but where & how do we find it?

First question: Does the voltage regulator have a good solid ground? If not, it won't work correctly and it will not make the charging sytem "come to life". Make sure the voltage regulator it is solidly grounded. This includes the ittle braid across any rubber anti vibration mounts!

If the regulator is properly grounded and still it does not charge, I would remove both wires from the generator's posts. Then I would ground the F post to the generator's frame, NOT the tractor's frame but to the generator's frame. Then I would take a jumper from the battery's NON GROUNDED POST to the GEN or ARM post. It may be labled A, G, GEN or ARM. Have seen 'em all. When you just brush this jumper across the generator's post it should spark rather stoutly and the generator should try to run like a motor.

If it DOES, your trouble is probably an open wire between the generator and the voltage regulator or between the regulator and the ammeter or the ammeter is bad or the regulator is bad or you have an open wire between the ammeter & the battery.

If there are no sparks as you brush this jumper across the post, either the generator is open (though the generator guy says not so) or you have a bad ground connection between the generator and the block.

Next I would run a jumper from the GROUNDED post of the battery to the frame of the generator. Not to any of it's brackets but right to a spot filed shiny and bare on the generator's housing! (Fix the paint later.) Brush that OTHER jumper across the A post now & see if it sparks! If it does and the generator tries to run like a motor, remove all the jumpers, remove the generator and then remove the generator mounting bracket from the block and CLEAN ITS ELECTRICAL CONNECTION TO THE BLOCK as well as the connections between the bracket and the generator!

Hope that helps.
 
Heres a few thoughts:

At the shop it may have been Polarized for Neg grnd although your tractor was originally Pos but as long as you re polarized it she should still be okay....

A solid state cutout has to be connected at correct polarity or it wont let the gennys current flow into the battery to charge it...If wired wrong all you do is reverse its leads....

You have NO VOLTAGE REGULATOR so it obviously does NOT need grounded,,,,,,,,you only have a solid state diode (cutout relay) a series pass through provided at right polarity

Of course the gennys frame needs a good chassis ground just like the battery well DUH

Failing the motor test at 6 volts puzzles me???? If I didnt know better Id still suspect the genny

The ammeter is like a near short circuit, there should be hot battery voltage on BOTH terminals with respect to frame ground, if its bad/open the gennys current cant charge the battery....

I do know on the SM 2029 JD M wiring diagram theres a minor mistake but I forget where???? BASICALLY The gennys output goes thru the diode then thru the ammeter then to the hot ungrounded battery post. If thats all a good circuit and she dont charge with a grounded Field Id still suspect the genny

John T
 
I have tried every tip I have gotten everytime I have asked about this problem. I am blue in the face from checking the connections so much. I am confident there is no wiring problems or connection problems at all on the tractor.
The connection from genny to cutout relay to ammeter to starter post is sound.
I appreciate everybodys help very much even afer yalls tips it still doesn"t charge. It has to be the genny.

Any idea why it motors with 12v battery and not 6v? And why does it spin but when I remove the jumper from field to ground it starts turning opposite direction?
 
What should voltage read at battery with tractor running?
Ammeter seems to function properly. Voltage at both posts, shows discharge with ignition on or lights on.
Forgot to metion that the genny actually charged but very weak before I took it to be overhauled.
 
A good and charged 6 volt battery ought to read around 6.3 volts setting, if hooked to a good charging system at high RPM it should rise to at least 6.5 and up to 7 +

Sometimes those switches dont have a good ground but when you dead ground the gennys FLD post she should still max high charge

Is the belt good n tight???? Genny have a good ground??? With gennys FLD grounded and if you jumped across the cutout at fast RPM if all else is okay but she dont charge well I STILL SUSPECT THE GENNY

John T
 
I run into that before. It has 2 wires switched at the brushes. I don't remember for sure but if I had it here I could trace it out. Find someone that works on them to check it.
 
Tried those ideas to JohnT, still no charge. The guy has already looked at it once since it was redone and he thought he fixed it. I guess I'm gonna take a loss and go somewheres else I have lost confidence in the guy. I'm already out over 200 bucks on it.
 
I just remembered that I had to reverse the field wires so the current went through backwards. If your generator was rebuilt with new field coils, they may have been wound wrong.
 
teddy52food, yep the guy replaced absoultely everything. Field coils, armature brushes, brush holders, bushings, bearings, etc.
 
Perhaps incorrect field coils (6 versus 12 volt etc) or wired wrong, they splice in the middle, one end to third brush, other end to splice then out to FLD post....CHECK THAT OUT

John T
 
I fought with my father-in-law's 8N until I was blue in the face. It turned out that the genny was not grounded properly. A jumper wire from the genny to a starter through bolt made it charge like a new one. We tried three different generators - wouldn't you think that all of that bolt turning would have made a good ground? The bracket to engine connection wasn't making good contact.
 
John T;
From the previous post this genny put out 40 amps on the test bench. The rebuilder had to have used 12v components and high speed to get that many amps. I think that's why it takes 12v to motor test it. Since a genny is only concerened with amps shoulden't it still charge a 6v?
 
No telling how fast that machine was turning, he didn't know how fast it was turning either. He even eventually admitted he didn't know much about six volt systems.

Still has to be something wrong since it spins one way during motor test and then starts spinning another way when I remove the jumper from ground to field.
I can't take it apart it has a tamper proof seal on the back and if I take it apart he said warranty is void. I'll take it to him and see what he says.
Before you know it spring will be here and I want to take it to some plow days. Time is running out.
 
Yep this whole thing seems screwed up IT SHOULD MOTOR FINE AT 6 VOLTS UNLESSSSSSSSSSSSSSSSS

as you mention it either has 12 volt fields accidentally installed OR IM STARTIN TO THINK THEY ARE WIRED WRONG OR REVERSED

YES a true proper wired 12 volt genny can easily charge a 6 volt battery YES its more a current source then a voltage device

The armature dont matter as much so if hes wired right Im still back to a genny problem like miswired or wrong field windings

John T
 
The direction of current through the fields affects the North/South MAGNETIC Polarity (which determines + - ELECTRICAL Polarity and if wired right one side becomes a North Pole and the other side a South Pole. One end of first field to a brush,,,,,,,,splice in the middle,,,,,output of 2nd field to FLD post.


Assuming shes wired right and all else is okay????? I STILL SAY THE GENNY ISNT RIGHT REGARDLESS WHAT HE SAYS (Fields, Field wiring, Field orientation)

John T
 
You ask about turning different directions????

If you reverse the fields magnetic polarity (N becomes S and S becomes N) it will turn opposite direction.......

A reverse direction of current flow changes magnetic polarity.........

Even with no field current flow (like if field isnt grounded) THE GENNY IF MOTORED CAN RUN due to the small strength RESIDUAL PERMANENT MAGNETISM in the soft iron field poles........

If the residual permanent magnetism is at opposite magnetic (N/S) polarity then the magnetic polarity of the current created electromagnetic field THAT COULD EXPLIAN DIFFERENT DIRECTION OF SPIN

HOWEVER once current is passed thru the fileds (if grounded) that would change the resisdual magnetism back to match the electromagnetic fields polarity and correct any opposite spin direction iffffffffffffffffffffff current indeed passed through BOTH fields in the correct direction for each provided they are wired right and in right orientation etc!!!!!!!

Soooooooo somwehere in the above theory coupled with the fields arent wired right or reversed or dis oriented (in mechanical mounting) and as this thread develops and you give us more info and if all else is okay??? (including diodes in right direction???)

I AGAIN SUSPECT THE GENNY and tend to agree with Teddy theres a field problem (wrong ones or mis wired or reversed or soemthing???)

Let us know

AGAIN this assumes alllllllll else is correct???

John T
 
When you motorize it, did you note that it turned opposite the way the engine turns it? I had put one together with used parts I had & ended up with what you have. I took the wire off the brush & grounded it, then run a wire from the field post to the brush so the current flowed backwards through the field. Then it motorizes right and charged too. Take it back & let us know what he did to correct it.
 
Just in case y'all missed it. I did mention that the generator actually did work on the tractor before I took it to be rebuilt just very weak.

When I find out something ill let y'all know.
 

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