165 Diesel alternator wiring?

[DLinMI]

I have a 165 diesel that had been converted to an alternator prior to my purchase. It has a GM 3 wire alternator with a built in regulator. I've tested it at the large post and it is working but must not be wired properly because the battery runs down. The only gauge that appears to work is the temp gauge and tach. It has a two wire push button ignition switch. Anybody help me wire this to charge the system? I'm open to replacing the oil pressure and ammeter, or should I install a voltmeter? I've searched and searched but can't find my identical situation. From what I've seen the wiring is different ammeter vs voltmeter and gas vs diesel and wiring the "exciter" wire. HELP! Thanks

 

[DLinMI]

I have a 165 diesel that had been converted to an alternator prior to my purchase. It has a GM 3 wire alternator with a built in regulator. I've tested it at the large post and it is working but must not be wired properly because the battery runs down. The only gauge that appears to work is the temp gauge and tach. It has a two wire push button ignition switch. Anybody help me wire this to charge the system? I'm open to replacing the oil pressure and ammeter, or should I install a voltmeter? I've searched and searched but can't find my identical situation. From what I've seen the wiring is different ammeter vs voltmeter and gas vs diesel and wiring the "exciter" wire. HELP! Thanks

Also, How does the ammeter come out of the dash?

 

[Agvg]

A voltmeter is more useful, it just sits in a rubber housing and can be pulled out.

 

[Smokepole62]

If you do not have the third "exciting" wire run through a warning light such as the schematic above, you will get a residual drain on the battery. This warning light acts as a diode switch to excite the alternator, but when shut off does not let voltage flow in the opposite direction. If this is the case, you could install a diode in the exciting wire to cure this. I bought a ten pk of 1000V -1Amp diodes on Ebay for not much money. This cured my problem with a hacked up harness.