Strange ford 8n voltage regulator issue

dkirwin87

Member
Hello everyone I recently purchased a 51 8n and have been sorting out the various issues. One problem I've come across is the battery is not charging. I tested the generator by connecting it to the battery and it motors fine. Checked the wiring and cleaned terminals and still no luck, so I purchased a new voltage regulator. Upon installing the new regulator and polarizing it, I started the tractor. Initially output on the amp gauge jumped up to +15 amps then settled down to +10, then suddenly the gauge read -10 amps I revved the tractor and it came back up to plus 5 then slowly dropped to 0 and now is back to the same reading the old regulator was, slightly negative due to the ignition system draw. Any ideas on what could be causing this? I am stumped.
Thanks for all your help! :?
 

Assuming your numbers are from the dash ammeter... do you get similar numbers with a multimeter?
If yes, then we have some digging to do.
If no, then swap out dash ammeter.

Since this tractor is new to you;
Does the wiring in general look good or need some work?

-CBull
 
I checked the voltage at the battery while the tractor is running and its clear that its discharging reading about 6.4 and it will drop as the tractor is run for lengthier periods. The wiring appears in generally decent shape, I did not notice any nicks or damage and the insulation is not deteriorated, I did clean up the grounds where they had been painted over to make sure there was a good ground.
 
Finding a good new 6 volt regulator for an N tractor is getting almost impossible. You may have stuck
contacts in the regulator. Lightly tap the regulator with a screwdriver or other tool. See if that
momentarily corrects the problem. If it starts charging but then goes back to discharge then most likely your
new regulator is bad out of the box. They may be adjustable but I have never been successful in getting one
to work that was acting up. The last time I needed a 6 volt N tractor regulator I had to buy three before I
got one that worked properly. I converted all three of my 8N's to 12 volt alternators just so I would not
have to deal with the frustration of trying to find a good regulator.
 
It has been my experience you have to buy at least three
regulators before you get a good one. Does not matter if
they are OEM or aftermarket.
 
dkirwin........first thing I'd do is RE-POLARIZE yer squarecan voltage regulator. Just "arc-spark" the side-by-side ARM and BAT terminals with screwdriver blade, engine OFF. You can use bailin' warr iff'n you want. The squarecan voltage regulator is NOT indestructible. From yer descriptions, sounds like one of the relay arms have become disconbobulated ...er... disconnected. You may haffta byte the bullet and buy a NEW squarecan voltage regulator and start all over. .......electrical Dell
 
Thanks for the help guys, I will give repolarizing again a shot. What seems strange is that it went to a strong discharge before crapping out, makes me second guess that there is some short in the system but it has never presented a problem before, I can use the tractor for days before it eventually drains the battery. Is there any source of regulators that is better than another?

(quoted from post at 12:28:03 05/20/15) dkirwin........first thing I'd do is RE-POLARIZE yer squarecan voltage regulator. Just "arc-spark" the side-by-side ARM and BAT terminals with screwdriver blade, engine OFF. You can use bailin' warr iff'n you want. The squarecan voltage regulator is NOT indestructible. From yer descriptions, sounds like one of the relay arms have become disconbobulated ...er... disconnected. You may haffta byte the bullet and buy a NEW squarecan voltage regulator and start all over. .......electrical Dell
 
(quoted from post at 16:56:10 05/20/15) Thanks for the help guys, I will give repolarizing again a shot. What seems strange is that it went to a strong discharge before crapping out, makes me second guess that there is some short in the system but it has never presented a problem before, I can use the tractor for days before it eventually drains the battery. Is there any source of regulators that is better than another?

(quoted from post at 12:28:03 05/20/15) dkirwin........first thing I'd do is RE-POLARIZE yer squarecan voltage regulator. Just "arc-spark" the side-by-side ARM and BAT terminals with screwdriver blade, engine OFF. You can use bailin' warr iff'n you want. The squarecan voltage regulator is NOT indestructible. From yer descriptions, sounds like one of the relay arms have become disconbobulated ...er... disconnected. You may haffta byte the bullet and buy a NEW squarecan voltage regulator and start all over. .......electrical Dell
/quote]When you have been at speed, charging and then slow the engine below point where gen voltage drops below the battery voltage, the battery now tries to discharge back thru the generator (discharge)........when all is well in the VR, this discharge lasts only a moment, as the cut out contacts open, thus disconnecting the generator from the battery. So, the discharge you observed would be normal, but only for a moment.
 
As low as -10amps? I do observe a constant drain of around 1-2 amps which I assume is just the constant draw of the ignition system.
 
(quoted from post at 17:27:39 05/20/15) As low as -10amps? I do observe a constant drain of around 1-2 amps which I assume is just the constant draw of the ignition system.
ou said you didn't understand the -10 for a brief period. I was merely trying to explain why you could observe such. Actually if the cut out contacts fail to open altogether & you stop the engine that discharge current should peg you meter negative, the generator should get hot, the wires to arm may even melt the insulation!
 
To verify that the generator is working, while it is running short the field terminal to ground while wawtching the amp meter. If the generator is good, the amp meter should show full scale charge. with it running at 3/4 speed, tap on the voltage regulator and watch the amp meter. If the regulator is bad it my show charge at times. Make sure the regulator has the ground wire from the generator connected to a good ground.
 
(quoted from post at 11:10:31 05/22/15) SO I hooked up the field terminal on the VR to a good ground and still nothing. What does that indicate?
ot much of anything, actually, since the generator armature may not be connecting to the battery. You need to simultaneously connect the Field to a good ground (tie the two barrel terminals together) AND jumper the BATT to ARM. This latter connection should be removed as soon as you stop the engine. If it charges like this, call generator good & regulator bad. All of course assumes wiring is correct.
 
Ok so with field connected to ground and Bat and Arm connected together. The generator will motor when bat and arm are touched but still no charging while running the engine.
 
(quoted from post at 12:11:08 05/22/15) Ok so with field connected to ground and Bat and Arm connected together. The generator will motor when bat and arm are touched but still no charging while running the engine.
ATT & ARM connected together while running engine at speed? What are you relying on as an indicator of whether charging or not?
 
Yes with batt and arm connected and operating full throttle field and field grounded to the chassis at the voltage regulator ground. I get slight discharge reading on the ampmeter and a 6.2 voltage reading at the battery.
 
(quoted from post at 12:21:27 05/22/15) Yes with batt and arm connected and operating full throttle field and field grounded to the chassis at the voltage regulator ground. I get slight discharge reading on the ampmeter and a 6.2 voltage reading at the battery.
"Yes with batt and arm connected and ...."
BATT & ARM jumpered together, not just connected to generator & VR. OK?
If that is what you did, then jumper directly from generator ARM to battery's ungrounded terminal & monitor batt voltage..
Ammeter now will not be in circuit & Field still need to be grounded. Results? Back in hour.
 
Right those results were with Batt and Arm jumpered at the voltage regulator and field is grounded at the vr ground to chassis where the generator ground wire also grounds.
 
Dirt what jmor said. Ground the field at the Genny, not the reg, in case the wires are broke between, and if nada, then jump arm at Gen to bat term on reg, if nada on amp meter, jump arm on Gen to battery hot instead and do a before/after voltage check
 
Ok finally got a chance to test that. With field to a good ground from the generator and the arm attached to bat terminal at the regulator i get -10amps reading on the amp meter.
 
(quoted from post at 14:37:42 06/03/15) Ok finally got a chance to test that. With field to a good ground from the generator and the arm attached to bat terminal at the regulator i get -10amps reading on the amp meter.
ell, sir, that doesn't mean anything. As I told you before, "Ammeter now will not be in circuit & Field still need to be grounded." Instead of looking at ammeter, which is now NOT in charging circuit, measure voltage at battery, post to post.
 
Ok field post tied to ground post at the generator and armature at generator connected to hot battery terminal on the battery. Before battery reading 6.42 Volts. With everything connected engine running at middle speed 7.1 Volts at the battery.
 
(quoted from post at 14:44:09 06/09/15) Ok field post tied to ground post at the generator and armature at generator connected to hot battery terminal on the battery. Before battery reading 6.42 Volts. With everything connected engine running at middle speed 7.1 Volts at the battery.
hat IS charging.
 
Right, so it seems to me then that its either the voltage regulator or the wiring. any way to test the wiring while bypassing the VR?
 
(quoted from post at 00:56:12 06/10/15) Right, so it seems to me then that its either the voltage regulator or the wiring. any way to test the wiring while bypassing the VR?
f you look back thru this thread, we have done that, more or less. I say more or less, because earlier we were relying on the ammeter as an indicator of charge AND it could be bad or wired into the circuit wrong. Another difference was in the FIELD GROUNDING...........EARLIER DONE AT THE vr AND LATER DONE AT THE GENERATOR FIELD TERMINAL. You could go back to that early VR bypass arrangement where we grounded the field at the VR and jumpered BATT to ARM at VR AND this time monitor battery voltage as well as ammeter to possibly learn whether charging but no ammeter indications or not, even with battery voltage rising.
 
So I replaced the wiring harness and double checked all connections as per the wiring diagrams. The old harness was somewhat deteriorated so figured it best to continue trouble shooting with a proper harness. Started the tractor up and drove it around did not appear to be charging, although at one point ampmeter did show slightly positive. When i shut the tractor off, the generator now is motoring, tried re polarizing field to bat terminals and the wire heated up and sparked but when the jumper was removed generator starts motoring again.
 
(quoted from post at 14:02:12 07/01/15) So I replaced the wiring harness and double checked all connections as per the wiring diagrams. The old harness was somewhat deteriorated so figured it best to continue trouble shooting with a proper harness. Started the tractor up and drove it around did not appear to be charging, although at one point ampmeter did show slightly positive. When i shut the tractor off, the generator now is motoring, tried re polarizing field to bat terminals and the wire heated up and sparked but when the jumper was removed generator starts motoring again.
rying to motor with no jumpers installed, mean that cut out contacts in VR are stuck closed. Additionally polarizing by, " tried re polarizing field to bat terminals and the wire heated up and ...", only serves to burn up the VR field contacts. Proper polarization is by momentarily shorting or jumpering the BATT to ARM terminals.
 
I had thought about the contacts, but I also read that the generator itself can reverse polarity and that the generator is re-polarized by connecting field and batt?
 
(quoted from post at 16:25:20 07/01/15) I had thought about the contacts, but I also read that the generator itself can reverse polarity and that the generator is re-polarized by connecting field and batt?
have no doubt that you did read that polarization method somewhere. Problem is that it does not apply to your generator type, but rather to another generator type.
 
So replaced the VR with a new one and again it seems to be the same issue. Removed old one, installed new with battery disconnected. Then reconnected battery polarized by placing a jumper between bat and arm terminals on the VR. Appears to be slight charge initially on the ampmeter and then drops to 0 and then slightly below 0. No charge reading on multimeter (6.3 Volts at Battery). What else could it be, new wiring harness, generator appears good will pass the motor test and charged at 7.2 volts with the VR bypassed?
 
(quoted from post at 15:15:17 07/06/15) So replaced the VR with a new one and again it seems to be the same issue. Removed old one, installed new with battery disconnected. Then reconnected battery polarized by placing a jumper between bat and arm terminals on the VR. Appears to be slight charge initially on the ampmeter and then drops to 0 and then slightly below 0. No charge reading on multimeter (6.3 Volts at Battery). What else could it be, new wiring harness, generator appears good will pass the motor test and charged at 7.2 volts with the VR bypassed?
ow that you have a new wiring harness, we need to re-run an earlier test to verify the new wiring. Jumper Field to VR base(ground) and jumper VR terminals BATT & ARM together with engine at speed & monitor both ammeter & battery post to post voltage.
What see?
 
Ok finally got a chance to test that out. With the jumpers hooked up that way field to ground and Batt jumpered to arm. I get a slight negative reading on the amp meter about -2 amps and 6 volts across the battery terminals. When the tractor is shutoff the generator motors with the jumpers in the configuration until batt and arm are disconnected.
 
(quoted from post at 13:39:00 08/06/15) Ok finally got a chance to test that out. With the jumpers hooked up that way field to ground and Batt jumpered to arm. I get a slight negative reading on the amp meter about -2 amps and 6 volts across the battery terminals. When the tractor is shutoff the generator motors with the jumpers in the configuration until batt and arm are disconnected.
1- July 6 you said it produced 7.2v at battery, but Aug6 you say 6v.......what has changed?
#2- When you stop engine & generator is motoring with jumpers in place, what is ammeter showing?
 
#1 In that test field was tied to the ground terminal at the generator and armature was tied directly to the negative terminal at the battery completely bypassing the voltage reg and wiring.
#2 Ampmeter shows about a 8 amp discharge with the tractor off and generator motoring.
 
(quoted from post at 16:01:18 08/06/15) #1 In that test field was tied to the ground terminal at the generator and armature was tied directly to the negative terminal at the battery completely bypassing the voltage reg and wiring.
#2 Ampmeter shows about a 8 amp discharge with the tractor off and generator motoring.
would go back & ground the generator field at the generator (the two terminals on barrel of generator tied together).
 
Ok tried grounding field to ground at the generator no difference -2 amps on ampmeter and 6 volts at the battery.
 
(quoted from post at 16:46:16 08/06/15) Ok tried grounding field to ground at the generator no difference -2 amps on ampmeter and 6 volts at the battery.
ell, go ahead with next two steps while measuring volts across battery & leaving field grounded at generator.
#1 BATT to ARM at VR.
#2 ARM at generator to ungrounded battery post.
 
#1 BATT to ARM at VR.
No charge -2 amps and 6 volts
#2 ARM at generator to ungrounded battery post.[/quote]
Generator motors and sparks when connected to battery but -2 amps and 6 volts across the terminals
 
(quoted from post at 18:12:35 08/06/15) #1 BATT to ARM at VR.
No charge -2 amps and 6 volts
#2 ARM at generator to ungrounded battery post.
Generator motors and sparks when connected to battery but -2 amps and 6 volts across the terminals. [u:0ffa1fd672]WHEN THE ENGINE IS RUNNING AT SPEED.[/u:0ffa1fd672] yes/no? If the belt is driving it at high engine speed, you can't know that it is "motoring".
 
Well the generator motors with the engine off. When I start the engine and connect the armature to batt it sparks.
 
(quoted from post at 19:02:48 08/06/15) Well the generator motors with the engine off. When I start the engine and connect the armature to batt it sparks.
nd when running & connected, it shows -2A and 6v....is that correct?
If yes, then I still ask, what is different from a month ago when those same connections netted 7.2v?
 
I'm getting short on ideas, but try this: Remove Field wire from generator. Remove ARM wire from generator. Connect a jumper from Field to Ground (that is tie the two gen barrel terminals together). Jumper generator rear terminal/Armature to un-grounded battery post and immediately start engine & run at speed & measure voltage across battery post. This removes all tractor wiring from charging circuit, leaving only the generator and battery.
As an aside, are you positive or negative ground? i.e., which battery post is tied to chassis?
 
I have no idea why its no longer charging in that configuration. I even tried grounding field to battery ground thinking maybe it was a poor connection to the other terminal on the generator still no dice.
 
Ok same result disconnected field and arm from the wiring harness at the generator jumpered field to the ground terminal on the generator arm back to the negative battery terminal (I am positive ground) I get a slight negative amp draw and 6 volts across the battery terminals.
 
The last instructions I gave you result in only gen & battery, no tractor wiring. If it won't bring battery up above 6v like this, I believe we must believe generator is bad.
 
The generator can motor. Seems bizarre it would suddenly go south. I was previously getting voltage this way but the voltage regulators would show charging for a minute or two and then burn out.
 
(quoted from post at 20:11:00 08/06/15) But if the can motor wouldn't it be good?
oes not have to be good, because they can motor on only residual magnetism, but only put out about 1v on residual. Need field current in order to produce more voltage. You can measure field current with meter set & wired for measuring amperes, by inserting ammeter in place of the Field to Ground jumper in my last sketch & then take a reading when connecting BATTERY to ARM. Should see about 2 to 3 amperes. ALSO, when you are motoring it, you should see a difference in speed with Field grounded & not grounded. If no speed difference, then probably bad fields.

You could also [u:7e536d9ebb]not[/u:7e536d9ebb] connect ARM to BATTERY (but leave GND to Field jumper in place) and connect an ANALOG voltmeter from ARM to GND & measure running voltage. It should be very much above 6v, maybe 3 times 6, but don't run it long at such a voltage.
 
Ok measuring voltage with field jumped to ground and armature off generator back to ground I get 1 volt from the arm to the battery positive terminal.
 
(quoted from post at 21:12:25 08/06/15) Ok measuring voltage with field jumped to ground and armature off generator back to ground I get 1 volt from the arm to the battery positive terminal.
e do not communicate well. I do not understand your statement, "and armature off generator back to ground I get 1 volt from the arm to the battery positive terminal.".. Please explain further.
 
So leaving the two barrel connectors for field and ground jumper ed together. With the engine running at speed i get a reading of 1 volt from the armature terminal on the generator to the positive terminal of the battery on my analog multimeter.
 
(quoted from post at 22:39:53 08/06/15) So leaving the two barrel connectors for field and ground jumper ed together. With the engine running at speed i get a reading of 1 volt from the armature terminal on the generator to the positive terminal of the battery on my analog multimeter.
s the positive terminal of your battery grounded to tractor chassis?
 
(quoted from post at 23:14:59 08/06/15) Yes it has a clean ground to the Chassis.
o that means that you measured 1 volt from ARM to ground........right? That to me says, no field current. Which says something wrong inside generator. I/we could eventually figure it out over these messages, but will take longer than if you have a decent generator shop around. I will work with you if you wish to pursue.
 
(quoted from post at 14:05:55 08/07/15) Sure what would the next couple of steps be? Remove and disassemble generator I assume?
would use OhmMeter to measure Field to Armature resistance as a start, so as to know if I will be looking for an open or shorted field connection.
Then carefully disassemble trying not to disturb potential evidence to the problem.
 
(quoted from post at 15:31:20 08/07/15) So resistance from the field terminal to the arm terminal on the generator reads 0 ohms.
ero is a dead short. Should be a bit over 3 Ohms.
 
Ok so with the generator opened up. I can see some visible nicks in the armature wire but even with those taped up i still dont get any resistance across field and arm.
 
(quoted from post at 16:48:34 08/07/15) Ok so with the generator opened up. I can see some visible nicks in the armature wire but even with those taped up i still dont get any resistance across field and arm.
hat you see should look like a coil wound & wrapped surrounding both iron pole pieces, with the two coil connected together with an insulated wire. Also a wire coming off one coil going to the field terminal post & the other to the ARM terminal post. Are those wires all intact?
 
Probably should do a little terminology check here, too. Zero Ohms.....is that the same reading you obtain when you touch the two meter probes together? And clearly discernible from the reading when the two probes are separated?
 
Yes same reading as when the two probes are connected. When the probes are separated it reads infinite. Also there seems to be no magnetism to the fields, is it possible the generator lost its residual magnetism and that's why its failing to generate?
 
(quoted from post at 17:15:58 08/07/15) Yes same reading as when the two probes are connected. When the probes are separated it reads infinite. Also there seems to be no magnetism to the fields, is it possible the generator lost its residual magnetism and that's why its failing to generate?
irst, did the wires look as I described? True without field current & with no residual, it would not generate, but yours did generate 1.4 v, indicating that some residual was present. If the field windings & connections were all OK, then you would have magnetized the pole pieces many times in all the operations we have done!
 
The field wire appears intact, the armature wire had some small nicks in it. I taped those up just to test and it still reads 0 ohms.
 
(quoted from post at 17:26:23 08/07/15) The field wire appears intact, the armature wire had some small nicks in it. I taped those up just to test and it still reads 0 ohms.
'm really having a hard time understanding zero, because the two wires in question come from two separate coils, separated by several inches. It seems unlikely that such winding shorts would occur. Try measuring from ARM to case and from Field to case, while being certain that neither wire from the coils have any contact with the case. Should be infinite.
 
(quoted from post at 17:36:32 08/07/15) Ok Field to case reads infinite
Arm to case reads infinite
and ground terminal to case also infinite.
rm to case & Field to case is fine, as that indicates coils & wiring are not shorted to case or pole pieces. Gnd terminal is a simple bolted connection and should be Zero gnd terminal to case.
 
Ok rechecked ground to case its 0 wasn't getting a good connection for some reason initially. The magnets have basically no pull can easily hold a nail or other iron object in there and they dont pull it at all.
 
(quoted from post at 17:49:57 08/07/15) Ok rechecked ground to case its 0 wasn't getting a good connection for some reason initially. The magnets have basically no pull can easily hold a nail or other iron object in there and they dont pull it at all.
ith easy access to those two wires, you can connect jumpers from them to battery & see if nail is attracted to either pole piece. You can also watch for any sign of a spark when connecting, but if the Zero Ohm reading is valid, I would expect no magnetic attraction and a lot of sparks, since Zero is a short circuit.
 
Ok connected field and armature up to the battery the leads off the windings and got a strong magnetic field and no sparking.
 
(quoted from post at 18:16:21 08/07/15) Ok connected field and armature up to the battery the leads off the windings and got a strong magnetic field and no sparking.
oth sides?
Need to repeat resistance measurement........zero suspect. Be sure RX1 selected & meter zeroed. Any residual now?
 
Ok let it sit connected to the battery for a couple of minutes and now it seems to have a nice residual pull. I guess reassembly is the next step. I have already lightly sanded and cleaned up the communicator. and greased the bearings.
 
(quoted from post at 18:58:31 08/07/15) Ok let it sit connected to the battery for a couple of minutes and now it seems to have a nice residual pull. I guess reassembly is the next step. I have already lightly sanded and cleaned up the communicator. and greased the bearings.
rush length enough for good force? Slots between commutator segments OK? Mica not higher than copper? Upon re-assembly be sure all wires are in good position for not rubbing & not shorting to housing, etc. When back together, re-meas resistance as a verifier. Then motor it again and this time look for motoring speed difference when Field is grounded vs un-grounded. When back on tractor connect using the two jumper simple diagram I posted where no tractor wiring is involved. Let me hear from you.

Over 1400 people eye balling you! :)

If not back together yet, you might verify no shorts from commutator to armature shaft.
 
Ok so testing it on the bench. Hooked up to the battery with electric motor turning the generator. reading 4ohms between field and arm. When testing field jumper-ed to ground which is connected to + on the battery. Armature connected to - side of the battery. I get 6 volts from arm to + and 6 volts across the battery terminals. The generator motors fine in this configuration as well. when the electric motor is shut off.
 
(quoted from post at 20:04:34 08/07/15) Ok so testing it on the bench. Hooked up to the battery with electric motor turning the generator. reading 4ohms between field and arm. When testing field jumper-ed to ground which is connected to + on the battery. Armature connected to - side of the battery. I get 6 volts from arm to + and 6 volts across the battery terminals. The generator motors fine in this configuration as well. when the electric motor is shut off.
don't know how long or what rpm you are spinning it, but if it won't raise the battery voltage in a few minutes, it is not charging.
 
Yeah no improvement. Voltage at 6. What else could be causing the lack of output aside from the lack of continuity between field and arm?
 
See attached photo of brushes and communicator do either of them look too worn out?

mvphoto25627.jpg


mvphoto25628.jpg
 
No, the brushes look fine, commutator ok as far as I can tell from picture. Have you looked for what should be infinity resistance from commutator segments to armature laminations & shaft?
 
Ok I assume the armature lamination is the fat silver portion in the middle. I get infinite resistance between there and the communicator segments. I also get infinite resistance between the communicator and the shaft. But between the silver armature lamination and the shaft i get 2 ohms of resistance.
 
(quoted from post at 21:44:56 08/07/15) Ok I assume the armature lamination is the fat silver portion in the middle. I get infinite resistance between there and the communicator segments. I also get infinite resistance between the communicator and the shaft. But between the silver armature lamination and the shaft i get 2 ohms of resistance.
hat all sounds OK.

This is a long shot, but are you spinning it in the same direction (CW) as when installed on tractor. It does matter.
 
(quoted from post at 21:55:29 08/07/15) Yes spinning it clockwise when facing the pulley.
K, run it disconnected from battery & see what voltage you see on ARM.
 
Ok with field jumper-ed to ground and the generator running on the motor I get 1 volt between arm and ground terminals.
 
Ok dissassembled and reassembled tightened everything up. I now get 4 volts with field and ground connected. Across arm to ground terminal with the multimeter
 
(quoted from post at 22:26:01 08/07/15) Ok dissassembled and reassembled tightened everything up. I now get 4 volts with field and ground connected. Across arm to ground terminal with the multimeter
o good. Something wrong in that generator and the only thing that I can think of that we haven't verified is the armature & without a Growler, I do not know of a way to do that. Gen shop in your area?
 
Is it possible its not spinning fast enough? The output pulley on this motor is quite a bit smaller than the drive pulley on the tractor and it does output more voltage if i really snug it up although not much above 4.
 
(quoted from post at 22:51:17 08/07/15) Is it possible its not spinning fast enough? The output pulley on this motor is quite a bit smaller than the drive pulley on the tractor and it does output more voltage if i really snug it up although not much above 4.
725 ought to be enough. 8N step up via pulley size is 1.4.. Don't have data sheet on your generator but on another 1950's generator the data sheet shows that it will reach max output at 1925rpm. I have done same with elect motor where my pulley ratio spun gen at 1400 rpm & all was well.
 
Would you happen to have the spec sheet for the 8n generator? I would just like to give that to the guy when I have it rebuilt.
 
(quoted from post at 19:54:19 08/08/15) Would you happen to have the spec sheet for the 8n generator? I would just like to give that to the guy when I have it rebuilt.
orry, I do not. 20A, generator.
 
Well I am at my wits end. Took the generator to a generator shop guy says it tested fine and to bring in the regulator, bring the regulator he says that it's no good and gives me a new one. He cleaned up and reconditioned the generator as well while it was there. So reassemble everything fire up the tractor IT CHARGES! not high but just below 10 amps and 7 volts at the battery. That lasts about 5 minutes and then same as always amperage drops to 0 and no charge 6.2volts on the battery. What the hell could this be it seems i have checked and verified every component of the entire charging system and i have this same bizarre issue every time i replace a regulator. charges for a few minutes then dead.
 
oNCE THE BATTERY IS SFULLY CHARGED, the amps should drop off to protect the battery from being over charged. What happens if you let it set over night and restart it? Is it charging for a while then?
 
Should they drop off completely though? Even if i turn the lights on it will go to full discharge and not compensate. At what battery voltage should the charging kick back in?
 

I have had trouble with regulators in the past not working right out of the box. I would think that with the lights on it should not show full discharge. Any corroded electrical connections will cause problems as well as ground connections.

The closing voltage of the cutout relay should be 7.8 - 8.5 volts and the opening voltage should 1/2 to 1 1/2 volts less than the closing voltage.
 
Ok Yeah i am not seeing anything close to that. It topped out at 7V before the regulator failed. I have cleaned and checked all grounds rebuilt generator replaced regulator several times. Installed a new wiring harness and still the same issue as the beginning. Install a new regulator tractor charges for a few minutes then charge gradually drops then nothing. Slow discharge from the ignition circuit eventually kills it.
 
(quoted from post at 17:06:35 08/31/15) Ok Yeah i am not seeing anything close to that. It topped out at 7V before the regulator failed. I have cleaned and checked all grounds rebuilt generator replaced regulator several times. Installed a new wiring harness and still the same issue as the beginning. Install a new regulator tractor charges for a few minutes then charge gradually drops then nothing. Slow discharge from the ignition circuit eventually kills it.
egardless of what your generator shop said, if you can't make it charge with that simple two wire diagram that I posted awhile ago, then something is not right with your generator. Could be intermittent problem.
 
See the thing is it does charge. but then the regulator seems to blow out and it quits charging. Then if i get another regulator it charges and then the regulator blows again. What could be causing the regulators to fail after a few minutes of charging?
 
(quoted from post at 18:13:18 08/31/15) See the thing is it does charge. but then the regulator seems to blow out and it quits charging. Then if i get another regulator it charges and then the regulator blows again. What could be causing the regulators to fail after a few minutes of charging?
o disrespect, no harm intended, but I really doubt that the generator/battery system is "blowing out" multiple regulators.
As said about the two wire connection, if you can't consistently make it charge with that connection, it isn't a regulator problem.
Send me one, two, a number? of your "blown out regulators" & I'll bet a beer that I can show that some or all are good.
 
I will rerun the 2 wire test with the generator on the tractor. I know on one of the regulators i opened up the contacts had fused together on one of the circuits.
 
(quoted from post at 18:26:11 08/31/15) I will rerun the 2 wire test with the generator on the tractor. I know on one of the regulators i opened up the contacts had fused together on one of the circuits.
f BOTH sets of contacts were fused together, then it would be stuck at full/maximum charge. You are not seeing that.
 
Ok tested the generator again with the electric motor. I got a consistent 7.1 volts compared to the 4.5 volts I got at the same motor speed prior to having the generator rebuilt. The previous vr that fried did not have both sets of contacts fused. One set still moved freely the other was melted together at the contacts. What else could be causing these symptoms of charges for a few minutes then gradually stops charging and never charges again.
 
Well finally solved the issue at least with the rebuilt generator. Turns out it must have been the old metal studded link belt on the tractor that was slipping. Even though tension was good and the fan and water pump appeared to be turning at full speed it must have been slipping under load. Replaced the belt and now get a healthy 7.2 volts at the battery and no discharge with lights on. Thanks everyone for all your help!
 
That was a tough row to hoe. Thanks for posting back
and letting everyone know what the final cure was!
 

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