9n all new wiring assistance

[bshipley78]

charged up the battery and tested it and I got 12.74 volts then with the tractor running the battery read 12.38 volts and 12.30 volts coming off the post from the alternator

 

[Jim.ME]

charged up the battery and tested it and I got 12.74 volts then with the tractor running the battery read 12.38 volts and 12.30 volts coming off the post from the alternator

With the engine running about half throttle use a jumper wire to momentarily put battery power to the #1 spade terminal of the alternator. Without slowing or stopping the engine check the voltages again and report back. if the voltages are higher and rising, I would say you have a three-wire alternator, and it needs to be wired accordingly.

 

[bshipley78]

Regardless of wire size at this point.

You first say you are getting no charge to the battery, and later you say the ammeter is only getting to just before 10. 10 on the plus or minus side? If wired correctly, 10 on the plus would be a charge and 10 on the minus would be a discharge. To confirm charge or not, what is the voltage at the alternator output post when running and what is the voltage at the battery when running?

Post a picture of the diagram you used for wiring it. What gauge wire do you have between the alternator and ammeter? Is the wire from the ammeter to the battery alone on one post, with all other wires on the other post? If you wired from the alternator to the battery, you bypassed the ammeter, and it won't read charge, only discharge caused by loads going through it.

The wire from alternator to power post and the jumper is 14ga.

 

[deanostoybox]

With the engine running about half throttle use a jumper wire to momentarily put battery power to the #1 spade terminal of the alternator. Without slowing or stopping the engine check the voltages again and report back. if the voltages are higher and rising, I would say you have a three-wire alternator, and it needs to be wired accordingly.

In the case of the "three wire alternator" (10si) the #2 terminal will need to be powered continuously in order for the alternator to produce power. The #2 terminal supplies power to the voltage regulator and also allows the regulator to sense the battery voltage. When battery voltage is less than the set point which is typically 14.7V, the output transistor of the regulator switches one end of the rotor winding to ground. When the battery voltage is greater than the set point, that end of the rotor winding is disconnected from ground. The #1 (excite) terminal, when energized externally, provides power to the other end of the rotor winding magnetizing the rotor, which when turning generates current in the stator. Once there is current in the stator, the diode trio supplies current to the rotor and the #1 terminal.

 

[Jim.ME]

In the case of the "three wire alternator" (10si) the #2 terminal will need to be powered continuously in order for the alternator to produce power. The #2 terminal supplies power to the voltage regulator and also allows the regulator to sense the battery voltage. When battery voltage is less than the set point which is typically 14.7V, the output transistor of the regulator switches one end of the rotor winding to ground. When the battery voltage is greater than the set point, that end of the rotor winding is disconnected from ground. The #1 (excite) terminal, when energized externally, provides power to the other end of the rotor winding magnetizing the rotor, which when turning generates current in the stator. Once there is current in the stator, the diode trio supplies current to the rotor and the #1 terminal.

Thank you, I stand corrected on the #2 wire, bshipley78 will need to apply battery power to the #2 terminal as well as the #1 terminal to test.

 

[Eman85]

charged up the battery and tested it and I got 12.74 volts then with the tractor running the battery read 12.38 volts and 12.30 volts coming off the post from the alternator

Your alternator isn't doing anything. Do what deanostoybox said to do and check voltage.