1 wire alternator delco

[Delmer]

If you put the VOLTMETER where the AMMETER was and used the same wires, it would not read volts correct, because it would be wired to measure AMPS. Test that voltmeter on your battery, I don't think you burned it out reading 12V, which is what it is meant to read (hint, it should read 12 V when hooked to your battery, and 12V when you install it correctly with the key "on" and 13-15V when the alternator is working).

The alternator needs to be hooked directly to the battery or the big lug on the starter that connects to the battery. The voltmeter needs to be connected to the ignition side of the key switch, and GROUND in order to read voltage.

 

[logue]

I would recommend that you install a 0 to 30 ammeter. You probably destroyed the voltmeter if you didn't wire it correctly.
Did you change the wiring when you removed the idiot light ? All you needed to do was remove the bulb from the socket.
Did the alternator ever charge while you have owned the tractor ?
I'm thinking something isn't wired correctly on the ignition switch.
Look at that diagram in post # 39. That is what you should have.
One exception is the ammeter wire can go on the starter battery connection post.
There is also an outside chance there is a faulty diode in the alternator allowing a parasitic draw on the battery.

Ref: the diode... How old is the alternator ? Diodes (located in the alternator) are a 1 way check valve for electricity. After 10 years or more, diodes begin to decay and allow electrical leakage backwards. With your ignition off (key removed condition) the defective diode will allow slow voltage to leak backwards from the battery thru the alternator to ground causing the battery to be low voltage or to go dead. The fix is to replace the diode or the alternator. Replacing the alternator is the safest and simplest way to fix the problem. This is a problem on lawn mowers too. Simple to troubleshoot with a mutlimeter on the amp setting.

 

[Tinkerer]

Welcome to HEF, Logue !
Excellent information about a slow drain on a battery.
For anyone reading this that may not know, maybe you could post how to put the VOM on amp. setting into the circuit.
Another way that I am familiar with is to check for a very low AC voltage at the 2 battery posts with the engine running.