bad 12 volt conversion

JEC

Member
Not very knowledgeable about tractors and even less so on wiring so excuse bad terminology. Fergie TO30 has been converted to 12v somewhere down the line and the battery does not stay charged so I"m trying to track down the problem.
With the multimeter on the battery with tractor running, voltage is all over the place, so I read that usually means the Voltage Reg. is bad. I don"t think I have a voltage Regulator on it?
I guess the first step is trying to figure out this mess is, what is this part pictured below?
It has a green wire connected to the Ignition coil and a red wire that runs to the dash and is spliced to kill switch, and then runs toward the alternator, but is not connected to anything.
Hopefully this pic will work.




http://i1055.photobucket.com/albums/s509/jeclowers/fergpart.jpg
 
That piece you are reffering to is a ballast resistor. It cuts the voltage down going to the coil so it doesn't over heat. Most 12 volt conversions have that because they do not have a true 12 volt coil installed. If your tractor was converted with a GM 1 wire alternator and most of them are, the voltage regulator is contained in the back of the alternator itself. I have seen them short internally and drain the batteries. Get the alternator checked and if it isn't there then it is a wiring issue or a switch that has gone bad internally. Your meter going crazy is normal if the tractor has non resistor spark plugs installed and the meter is digital. Does your tractor have an amp gauge? Does it show discharge while the tractor is sitting still and not running?
 
hi,had similar problem,bought alternator off ebay,it has low rpm exciter in it,think it means the built in regulator,which is in the alternator kicks in at a lower rpm and that allows the system to start charging,so far so good,battery is staying charged amp meter shows that it is charging,before i bought new alternator I would have to rev engine real high before the amp meter would show that it is charging,sometimes would have to ride tractor around and rev engine before it would start charging with old alternator,not anymore,start tractor up and immediately starts charging,I think I bought it from triode diode or something close to that on ebay,happy,happy,happy now,took that from Phil on duck dynasty,good luck.
 
It has an amp guage on it that does not work. The wiring is pretty simple and not to hard to explain.
The 1 wire on the alternator is connected to the amp guage. Other side of amp guage is run to solenoid.
Both sides of start button go to the solenoid.
One side of kill switch to same side of solenoid.
Pos. battery cable from same side of solenoid to battery.
The peice that I now know is ballast resistor has green wire to ignition coil. Then a red wire that splices to kill switch and the other part goes toward alternator and is disconnected? Where should that go.
That is all there is to the wiring.
 
Jec,
I have some nice schematics for you. I did my TO35 without any trouble. Shoot me a e mail and I'll try to hook you up.
 
Anyone have any idea what the wire is that comes from the ballast resistor and splices into the kill switch and then heads in the direction of the alternator? It's broke and I don't know where this one is supposed to connect.
 
A TO30 with a starter button and a solenoid? Hmm...somebody has added some not needed stuff to it and made it more complicated than what it is. Do you have a test light. If you have a test light take the negative cable off the battery. Hook the alligator clip on the lead of the test light to the battery cable. Then touch the test light to the negative post on the battery. If there is a draw on the battery the test light will light up. Start unhooking wires one at a time until the light goes out. When it goes out, whatever wire is unhooked then you know it is in that circuit.
 
The charge wire from the alternator can't go to the amp gauge. It has to go the the kill side of the switch. I found the best place to attach that wire is to the positive side of the coil with the ignition "on" wire from the switch. The charge wire also needs a diode in it to stop the current back to the alternator with everything off and running the battery down when stopped. My auto parts house has a plug in for the alternator with the diode already wired in it and a inline terminal on it. About $7.00 and a clean installation.
Like others have said, get rid of the starter solenoid...they made a good system more expensive and not at all safe.
Irv
 

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