How to 3G Alternator

[JohnnyK]

Of course, but if his bulb burns out without another circuit in parallel, next time he starts the car, it won't charge.

Same page?

[Ron]

Of course, but if his bulb burns out without another circuit in parallel, next time he starts the car, it won't charge.

Same page?

Agreed. That's why I said, "once excited". Same page!
...If you agree he never said "turn off".

[Bitsyncmaster]

To sum it up you want any alternator to provide at least 12.6 volts with your load if your idling for a long time. With OEM fans (30 amps) blower on #4 (25 amps) headlights (15 amps) it would surprise me if any alternator could do that at 775 RPM idle.

Get lower power fans and LED headlights and you drop your load by 25 amps. If you have my idle ECU you can also bump the RPM up a little and get more power from the alternator at idle.

[Josh]

...would continue to put out, once excited....

[RamblinDMC]

I did this in one day and drove the car to a party that night. I might not have everything just right, but i can go back and do it again now that i have 1.25 mega watts available. If anybody decides to do this upgrade, please post pics of your mounts.

Oh yeah! 1.25 MegaWatts! That funny line from that movie! What was it called again?

[Helirich]

Oh yeah! 1.25 MegaWatts! That funny line from that movie! What was it called again?

I went to a glass tinter the other day and the guy and his wife never saw the movie. (They were about 30)

[Helirich]

Your light should work if you:
Connect the aftermarket pigtail's (I), Green wire (OEM- Light Green with Red stripe), to the DeLorean's (L), Brown with Yellow stripe, wire.
The (S), White wire (OEM- White with Black stripe, or Black with White stripe), would go to the one terminal socket next to the 3G alternator's main (B+) terminal.
The (A), Yellow wire (OEM-Yellow with White stripe), can go on the main terminal as you have it, but it's better to put it as close to the Battery(+) post.

Update on wiring.

First, I want to say I think the way I had it wired created a "ghost draw" on the battery. I can't say for sure and I know that Deloreans are famous for this problem. I've read where people can't park the car for a month, but I think this would have gone dead in a few days. It seemed to me that overnight my battery would go way down. It's a brand new Optima and it would come right back once I start the car with this alternator, but it didn't do this before the alternator. My Bronco can be parked for several months and not go dead. After some testing, I found the Bronco's green wire has "switched power". (It only has power when the key is on)

My old "maybe stock" alternator had a seperate plug from a yellow wire with a red stripe, that I taped up. I checked it and found it was "switched power". I plugged the green wire into it and the ghost draw went away. The alternator charged fine, but of course, there was an issue. Now my battery light was on all the time. So I did some more checking and found back in the harness was a brown wire allready taped up. (Not by me) I tested that wire and it was switched power also. I swapped the green plug wire to it and all is normal. (It charges and the battery light is off.)

My question now, does this mean I'm depending on the battery light bulb? Ron, you said brown with yellow stripe. I don't see the stripe, but maybe it has faded. For now I'm going to leave it. I do still have the insulated plug on the yellow wire and I could just switch the green male plug to it in seconds if the light failed. That is assuming the yellow wire will still have power after that failure. Ron, since you seem to have a handle on this, I would appreciate a comment.

[Ron]

Update on wiring.

First, I want to say I think the way I had it wired created a "ghost draw" on the battery. I can't say for sure and I know that Deloreans are famous for this problem. I've read where people can't park the car for a month, but I think this would have gone dead in a few days. It seemed to me that overnight my battery would go way down. It's a brand new Optima and it would come right back once I start the car with this alternator, but it didn't do this before the alternator. My Bronco can be parked for several months and not go dead. After some testing, I found the Bronco's green wire has "switched power". (It only has power when the key is on)

My old "maybe stock" alternator had a seperate plug from a yellow wire with a red stripe, that I taped up. I checked it and found it was "switched power". I plugged the green wire into it and the ghost draw went away. The alternator charged fine, but of course, there was an issue. Now my battery light was on all the time. So I did some more checking and found back in the harness was a brown wire allready taped up. (Not by me) I tested that wire and it was switched power also. I swapped the green plug wire to it and all is normal. (It charges and the battery light is off.)

My question now, does this mean I'm depending on the battery light bulb? Ron, you said brown with yellow stripe. I don't see the stripe, but maybe it has faded. For now I'm going to leave it. I do still have the insulated plug on the yellow wire and I could just switch the green male plug to it in seconds if the light failed. That is assuming the yellow wire will still have power after that failure. Ron, since you seem to have a handle on this, I would appreciate a comment.

It sounds like you have it correct now. You can confirm that the brown wire's yellow stripe has faded (or is one going to the original) by disconnecting it and grounding it while the key is on. The bulb should light. Turn the key off and it should go off.

Yes, that means that the alternator could be dependent on the bulb to get the alternator started (probably not a problem with a 3G that turns fast enough. External regulator types will quit.). As mentioned before, you can prevent this by putting a 540 ohm resistor in parallel with the bulb. And a blown bulb should not cause a later model alternator to quit charging, once it began.

Some things you may not know or thought about:
When you turn the key on the light should come on - A bulb test.
The light should come on if the battery is supplying power, the alternator itself has a problem, or the belt breaks.
You loose all of these w/o the bulb!

Not sure about the yellow wire...my only thought there is that it the brown with yellow has a bulb in series with it and the yellow one probably does not. Probably don't matter now, but you might chase it down, pull fuses to find what's feeding it, etc ??? Just for your curiosity

[Helirich]

So I just found some new information. I found a wiring diagram for the 3G.

https://www.ford-trucks.com/forums/a...1&d=1347274212

If you look at it, you will find they have a wire from the plug center to a spade connector on the alternator. (Stator wire) I don't have this wire hooked up on my Bronco or the Delorean. The alternator seems to work fine. (Many years on the Bronco) To you electronic guys, Would I benifit by hooking it up?

[Helirich]

So I hooked up the stator wire and it charges .5 volts better at idle. Not sure if it was the cause. I guess I'll go back and hook it up on my truck also.