But...
An external regulator is not used with the 3G alternator ...

Hope this can help ya.

The plug that came with the regulator, the 3 wire plug that plugs into the 3G, how do you have it hooked up. Three wires white, green & yellow. White plugs back into the 3G. Yellow monitors the battery voltage. Some people connect it to the large post on the alternator some like to run it over to the battery terminal on the solenoid.Green? If you look at NOS681's picture, at the bottom left on the alternator there is a  LT Green/Red wire. That goes back to the ignition switch for switched positive. You need to connect that LT Green/Red wire to the Green wire in the 3G harness.

Last edited by wsinsle (4/06/2020 6:54 AM)

The green/red wire going to the 3G requires +12 Volt switched positive. I don't know how close to +12 that has to be. The 'I' terminal on the solenoid has +12 volts during start but drops to about +9 volts when key is in run. That is because of the #16 pink resistor wire.I would look for a solid 12 volt wire as stated in my last post. I think the fake regulator was made to work with a car with a ALT light not an amp meter. But if it works it works,
 

Last edited by wsinsle (4/06/2020 5:36 PM)

HudginJ3 wrote:

If the alternator makes 14V at both connections what is the advantage of one position over the other? I'm guessing less stress on the alternator?

This is my thought, You said the 'I' terminal measured < 5 volts with the green wire from the 3-G connected to it. This is the voltage that feeds the coil. At run, the coil is suppose to have around 9 volts. So you my be starving the coil for voltage during run, causing lesser spark. Now that you have moved the 3-G green wire from the the 'I' terminal, you could measure the 'I' terminal to see what your coil voltage is. You have  to be in Run position and the points closed or jumpered to get a correct reading. Caution don't leave it like this for a long period. That is why they created the Acc position on the ignition switch. Don't want to listen to the car radio for 1/2 hour in the run position if the motor shut off with the points closed. This can burn up a coil.

MS wrote:

Are you still running points ignition?  If not, 12 volts is the normal voltage supplied to a 12 volt coil and aftermarket or Duraspark II distributor.  i.e.; pink wire is typically removed or bypassed in that case.

Thanks for the heads up MS, I switched to the Duraspark ignition awhile back before the Mich bash.  After reading wsinsle's post I checked the voltage at the ignition wire. The wire on my car is brown not pink so I figured is was 12v. When I made the switch I used a Painless wire harness to fit connect the coil. The ignition wire on that harness is brown also. They both have 4.5v with the engine off. I didn't check it running. I was able to connect it to the keyed wire that the regulator used to be connected to. It's 12v. 

HudginJ3 wrote:

MS wrote:

Are you still running points ignition?  If not, 12 volts is the normal voltage supplied to a 12 volt coil and aftermarket or Duraspark II distributor.  i.e.; pink wire is typically removed or bypassed in that case.

Thanks for the heads up MS, I switched to the Duraspark ignition awhile back before the Mich bash.  After reading wsinsle's post I checked the voltage at the ignition wire. The wire on my car is brown not pink so I figured is was 12v. When I made the switch I used a Painless wire harness to fit connect the coil. The ignition wire on that harness is brown also. They both have 4.5v with the engine off. I didn't check it running. I was able to connect it to the keyed wire that the regulator used to be connected to. It's 12v. 

Sorry, bad assumption on my part, When you mentioned connection to the "I" terminal I assumed points. I removed that wire when I went to 12 volt coil.

I know after market harnesses don't use a pink resister wire they use a ballast resister. I'm curious, If you removed or had no ballast after up grading to Dura Spark, It's strange that there was such low voltage at the 'I' terminal. It should have been +12 like MS said.