1951 Super C Won’t Charge

[Norske]

The 1 & 2 terminals, both jumped to the Bat. terminal on the alternator is just a temporary connection for testing. To say it is not charging is that going by the ammeter? If so it may be bad, does it twitch at all towards discharge when you turn the ignition on. Check the voltage across the battery terminals with a meter to see if it is charging, should have something over 13 volts. The back bearing cap in the middle on the back of the alternator will magnetize when it is charging.

I have been checking voltage on both the battery and the battery post on the back of the alternator

 

[rustred]

I apologize to post another thread about this, but I have read the majority of the other threads and I have not been able to find a solution to my problem.

When I got the tractor it had a 3 brush generator and a 2 coil regulator and I could not get it to charge. I tried polarizing it and went through the steps to diagnose the issue, but couldn’t get it to charge. I replaced the regulator and polarized again, with still no luck. Had the generator tested and checked out. I determined that it was a possibility it could be mismatched because a 3 brush generator needs a cutout.

I decided to ditch the generator and convert it to 12V and install a one wire alternator and an ignition coil with an internal resistor. Still no luck. I then tried to excite the self exciting alternator by jumping the R terminal to the battery post on the alternator with no change. I thought maybe it wasn’t turning the alternator fast enough so I then installed a smaller pulley on the alternator, no change. I then took the alternator to a guy who replaced the 63 amp stator and replaced it with a 30 amp stator, no change (this would help it excite at a lower rpm, and a super c doesn’t need 63 amps). Took it back to the same guy and he converted it to a 3 wire alternator, it has a wire coming from the R terminal to the positive side of the ignition coil and a wire going from the F terminal to the battery post on the alternator, still no charge. (This would help it excite if it wasn’t self exciting)

I attached a file that explains how I have it wired.

-The ammeter is new
-Today while testing I stayed around 12.3 down to 12.2 volts all the time
-I use a voltmeter to measure voltage at the battery post on the alternator and ground to the alternator itself.
-I’ve tried it a full throttle, plus a little more by pulling on the rod going to the governor
-I replaced the wire going from the alternator to the ammeter, and ammeter to the positive post on the battery
-I replaced the wire going from the ignition switch to the same post on the ammeter as the alternator
-I’ve tried bypassing the ammeter and go directly to the positive post on the battery.
-I’m grounded from the negative post on the battery to the frame with a ground strap
-I’ve cleaned up ground connections on the frame where I ground the battery to, as well as where the alternator grounds its self to the bracket, and the bracket to the engine.
-currently I have the fuse pulled out for the lights because they have nothing to do with it charging, so I just wanted to eliminate them from the equation
-with the ignition switch off I still have 12 volts going to the alternator.
-with the ignition switch on I have 12 volts going to the positive side of the ignition coil and 6 volts on the negative side of the ignition coil
-one thing I found odd was that with the ignition switch on I had continuity from the negative terminal of the battery to the negative side of the ignition coil as well as continuity from the positive terminal of the battery to the negative side of the ignition coil, I’m not sure if that normal or not.
-is there something with the ignition system that could keep it from charging?

Any help is appreciatedView attachment 78536

U say it charges by bench testing it. So on the tractor is it getting power to excite its self ? Should be a very easy check , just run a 10 ga wire from alt. to the tractor battery for checking purposes and check what voltage u have. Plus u say ur checking voltage at the alternator and a no go. So it’s either the alt. Has a problem or it don’t have power to excite itself. Gotta start someplace.

 

[Norske]

The magnet does hold a wrench, but it still doesn't charge. I let it run for a few minutes and checked voltage periodically off of the battery post.

 

[used red MN]

Okay, no offense but that is a $15 dollar meter. Cheap meters can be affected by the electrical noise put out by points ignition. The wrench being held up there means that the voltage regulator is sending power to the slip rings on the rotor (spinning part) to magnetize it to make it charge. How about the ammeter does the needle move at all when you turn on the ignition? Do you have a headlight as asked above or an old 12 volt heater motor. I am suggesting you put some kind of a load through it to see if it reads anything.

 

[rustred]

The magnet does hold a wrench, but it still doesn't charge. I let it run for a few minutes and checked voltage periodically off of the battery post.

Ok what is your voltage at the black input wire and at the red 10 guage output wire ??never mind checking down the line.

 

[rustred]

Ok what is your voltage at the black input wire and at the red 10 guage output wire ??never mind checking down the line.

because i dont like that 8 volt reading unless your battery is that low or your meter is not correct. dont u have an actual battery load tester ? then if you have good readings keep going down the line , maybe your ammeter is koo-koo.

 

[Norske]

Okay, no offense but that is a $15 dollar meter. Cheap meters can be affected by the electrical noise put out by points ignition. The wrench being held up there means that the voltage regulator is sending power to the slip rings on the rotor (spinning part) to magnetize it to make it charge. How about the ammeter does the needle move at all when you turn on the ignition? Do you have a headlight as asked above or an old 12 volt heater motor. I am suggesting you put some kind of a load through it to see if it reads

because i dont like that 8 volt reading unless your battery is that low or your meter is not correct. dont u have an actual battery load tester ? then if you have good readings keep going down the line , maybe your ammeter is koo-koo.

My battery is that low, I have to jump it to start it now. It ran down from trying to test it.

 

[Norske]

because i dont like that 8 volt reading unless your battery is that low or your meter is not correct. dont u have an actual battery load tester ? then if you have good readings keep going down the line , maybe your ammeter is koo-koo.

I have also bypassed the ammeter. I will try bypassing is again tomorrow.

Okay, no offense but that is a $15 dollar meter. Cheap meters can be affected by the electrical noise put out by points ignition. The wrench being held up there means that the voltage regulator is sending power to the slip rings on the rotor (spinning part) to magnetize it to make it charge. How about the ammeter does the needle move at all when you turn on the ignition? Do you have a headlight as asked above or an old 12 volt heater motor. I am suggesting you put some kind of a load through it to see if it reads anything.

the ammeter would go down just a tiny bit when I turned the lights on when I had them hooked up before.

 

[rustred]

My battery is that low, I have to jump it to start it now. It ran down from trying to test it.

ok, so what is them 2 readings ?

 

[Norske]

ok, so what is them 2 readings ?

With the switch on and tractor not running, the voltage is currently 6.8 on the black wire going to the 1 terminal in the alternator, the voltage on the battery post on the alternator is 7.7. I am going to throw a battery charger on it for the night now.

 

[rustred]

With the switch on and tractor not running, the voltage is currently 6.8 on the black wire going to the 1 terminal in the alternator, the voltage on the battery post on the alternator is 7.7. I am going to throw a battery charger on it for the night now.

Ok. But it still should charge. I asked for the check right at the alternator as that eliminates other could be problems. Cause as ur saying it charges on the bench but not on the tractor. Should not matter where the alt is sitting if it’s grounded and getting power it should be putting out bigger power in simple words. Have u visually saw the output voltage when they tested it ? I think that alt. is the problem. I think the regulator is done for. Yes put a full charged battery in it and check those voltages again. Only thing would be it’s too low now to excite the alt. To make it charge but I don’t think so.

 

[rustred]

Ok. But it still should charge. I asked for the check right at the alternator as that eliminates other could be problems. Cause as ur saying it charges on the bench but not on the tractor. Should not matter where the alt is sitting if it’s grounded and getting power it should be putting out bigger power in simple words. Have u visually saw the output voltage when they tested it ? I think that alt. is the problem. I think the regulator is done for. Yes put a full charged battery in it and check those voltages again. Only thing would be it’s too low now to excite the alt. To make it charge but I don’t think so.

and one more thing you said it didnt charge with the generator either same deal as now, take battery booster cable and confirm you are grounded. connect to battery ground and other end to the alternator. never know,.. stranger things have happened!

 

[Norske]

and one more thing you said it didnt charge with the generator either same deal as now, take battery booster cable and confirm you are grounded. connect to battery ground and other end to the alternator. never know,.. stranger things have happened!

I did run an 8 gauge wire from the ground post on the alternator to the battery, I thought the same thing as well.

 

[used red MN]

Only thing would be it’s too low now to excite the alt.

rr, if it holds the wrench magnetically to the back bearing I am pretty sure it is exciting. Do you agree? Then all that has to happen is the stator picks of the current and the diodes sort it out into DC.
Norske, here is an analogue meter you can grab at Walmart. Swing needle multimeter. The problem with those is you have to run a 0-60 volt scale, so 20 volts is only a third of the way up on the scale so the volt divisions are pretty small. At least you can trust it when it shows a rise when the alternator is charging. Even if you have any kind of test light with an incandescent bulb (I am not sure how good a LED is at changing brightness in comparison to the voltage it sees) you should be able to see it brighten when it is charging as in have it running and plug in the wire on the one terminal. You should also hear it put a load on that little 4 popper.
I will add, it is not causing you a problem with the charging now I am pretty sure because it is transferring the amps to run the starter. But it is best if that ground strap went on a bolt that is tightening down directly on a casting not a sheet metal part as it is. On a starter mount bolt is ideal but as I said above direct to a casting is acceptable in my world.
Edit: Oops goofed that up, it didnt drop in the right place.

 

[used red MN]

I did run an 8 gauge wire from the ground post on the alternator to the battery, I thought the same thing as well.

This is the problem when a guy wants to short cut an explanation because he thinks everyone should be at his knowledge level. It is hard to understand what he is telling you, because he was clarifying about the ground because he want to make sure what he wanted you to test was going to be valid. He is telling you to essentially charge the battery but do it through the wiring to your alternator Bat. terminal. So your negative battery charger lead would go on the negative battery terminal and the positive on the Bat. terminal of the alternator. This would verify the same thing I was trying to have you do with the headlight or blower motor. If it charges the battery through the wiring we know it can at least carry some amount of load. Why wouldn’t it carry a load? Most likely because one of the terminals is not crimped on correctly. I know you completely replaced wire a second time, but not doing this type of work everyday day there is a possibility the same mistake was made twice. Also if your dash ammeter works it should show a charge when charging the battery through the alternator circuit. However, once the battery is charged and the charger amp level drops off this test will become less valid. In actually the best way to do this would be to connect the charger negative lead to the alternator case. Then you would also verify the ground path back to the alternator case is also good. He also assumed you don’t have a 100 amp boost charger that could burn up your wires and/or amp gauge.

 

[rustred]

This is the problem when a guy wants to short cut an explanation because he thinks everyone should be at his knowledge level. It is hard to understand what he is telling you, because he was clarifying about the ground because he want to make sure what he wanted you to test was going to be valid. He is telling you to essentially charge the battery but do it through the wiring to your alternator Bat. terminal. So your negative battery charger lead would go on the negative battery terminal and the positive on the Bat. terminal of the alternator. This would verify the same thing I was trying to have you do with the headlight or blower motor. If it charges the battery through the wiring we know it can at least carry some amount of load. Why wouldn’t it carry a load? Most likely because one of the terminals is not crimped on correctly. I know you completely replaced wire a second time, but not doing this type of work everyday day there is a possibility the same mistake was made twice. Also if your dash ammeter works it should show a charge when charging the battery through the alternator circuit. However, once the battery is charged and the charger amp level drops off this test will become less valid. In actually the best way to do this would be to connect the charger negative lead to the alternator case. Then you would also verify the ground path back to the alternator case is also good. He also assumed you don’t have a 100 amp boost charger that could burn up your wires and/or amp gauge.

Yes , the K I S S system , eliminate all the other who knows what connections and wiring ! Right from alt to battery.with the input voltage as I asked . Then if a no charge ,change or repair that alt. It’s not hard to figure this out. Who knows ??? Could have run that alternator with battery unhooked and there you go … you now have a no charge situation ! not there can’t see what’s taking place. I don’t usually get into electrical problems as there is lots of guys here that are good at it. But this is sounding stupid already.

 

[Norske]

rr, if it holds the wrench magnetically to the back bearing I am pretty sure it is exciting. Do you agree? Then all that has to happen is the stator picks of the current and the diodes sort it out into DC.
Norske, here is an analogue meter you can grab at Walmart. Swing needle multimeter. The problem with those is you have to run a 0-60 volt scale, so 20 volts is only a third of the way up on the scale so the volt divisions are pretty small. At least you can trust it when it shows a rise when the alternator is charging. Even if you have any kind of test light with an incandescent bulb (I am not sure how good a LED is at changing brightness in comparison to the voltage it sees) you should be able to see it brighten when it is charging as in have it running and plug in the wire on the one terminal. You should also hear it put a load on that little 4 popper.
I will add, it is not causing you a problem with the charging now I am pretty sure because it is transferring the amps to run the starter. But it is best if that ground strap went on a bolt that is tightening down directly on a casting not a sheet metal part as it is. On a starter mount bolt is ideal but as I said above direct to a casting is acceptable in my world.
Edit: Oops goofed that up, it didnt drop in the right place.il

I unhooked the starter while it was running to see if it was drawing extra amps, the tractor still stayed around 12.8 volts and kept dropping a little at a time. I put a battery charger on the alternator side of the battery wires and charged through the ammeter to the battery, the ammeter increased to show a charge. I did put a different alternator on it yesterday from Napa to see if it was the alternator itself, i didn’t do a lot of testing with that alternator because I wanted to make sure they’d take it back. I know this should be very simple, it’s just not adding up.

 

[Norske]

This is the alternator that I tried from Napa yesterday, is there any reason why it wouldn’t work?

https://www.napaonline.com/en/p/RAY2134011

 

[used red MN]

This belt is not tight enough!
May have to make a special wrench.
YT post on tighten belt on FSC

 

[used red MN]

This belt is not tight enough!
May have to make a special wrench.
YT post on tighten belt on FSC
View attachment 78723

The forum shows you looked at this several times yet haven’t replied. Don’t you believe me? Looking closer even the belt for the alternator does not look real tight. In your case if the belts are tensioned correctly you should be able to push on the alternator cooling fins with your thumb and rotate the engine. Hopefully you are not one of these guys that thinks if the belts are to tight it will knock out the bearings. If you want an alternator on there and you want it to charge the belts have to be tight.