Alternator Wiring Question?

[GoneLoco99]

I’m working on a ‘68 Imperial. Nothing under the hood is stock except the wiring. I’ve updated everything and am now ready to wire it up to run/charge.
I replaced the old OEM alternator with a 100amp alternator. Will I be using any of the stock wiring in this wiring cluster (see picture below) or run new? I’m lost when it comes to wiring. Not my strong point.

 

[Davea Lux]

Your stock wiring can not handle a 100 amp alternator. You will need to run the ammeter bypass and come up with an updated voltage regulator. If this alternator has an internal regulator, you can get rid of the external voltage regulator. The factory ammeter was designed for a maximum of 60 amps and you will toast it in short order trying to run 100 amps thru it. There are several posts on this site about how to do the ammeter bypass. The output lead from the alternator to the battery should be a #6 wire. Be sure to install an appropriately sized fusible link to protect the circuit. Unless you are planning to run a high output stereo system or large radiator cooling fan set, you really do not need this big of an alternator on this application. If you have converted to electronic ignition, be sure to run an electronic regulator if you need an external unit.

Dave

 

[Turboomni]

I have heard of horror stories that started out like this. Many a Mopar has been burned to ruin by ammeter, and wiring fires caused by what you are considering doing and doing it incorrectly.
Beware and do it correctly if you go through with this.

 

[GoneLoco99]

Your stock wiring can not handle a 100 amp alternator. You will need to run the ammeter bypass and come up with an updated voltage regulator. If this alternator has an internal regulator, you can get rid of the external voltage regulator. The factory ammeter was designed for a maximum of 60 amps and you will toast it in short order trying to run 100 amps thru it. There are several posts on this site about how to do the ammeter bypass. The output lead from the alternator to the battery should be a #6 wire. Be sure to install an appropriately sized fusible link to protect the circuit. Unless you are planning to run a high output stereo system or large radiator cooling fan set, you really do not need this big of an alternator on this application. If you have converted to electronic ignition, be sure to run an electronic regulator if you need an external unit.

Dave

I am running a HEI distributor. As for stereo or cooling fan, I am not.
I am not running any of the stock gauges either. Using all AutoMeter gauges now.
So I will not need to use any of the factory wiring harness, shown in my picture?

 

[413]

Why do you need 100 amps?

please list your electrical acccessories, stock and added.

 

[Davea Lux]

I am running a HEI distributor. As for stereo or cooling fan, I am not.
I am not running any of the stock gauges either. Using all AutoMeter gauges now.
So I will not need to use any of the factory wiring harness, shown in my picture?

The L shaped connector is for the Hot/Cold idiot lights. The loop connector was for the alternator output. The single straight black connector ran from the voltage regulator to the alternator field. If you are retaining the idiot lights, you can plug that lead back into the sensor on the water pump housing. You will need to replace the loop connector lead with a heavier wire. Depending on if your alternator needs a voltage regulator, you might need the straight black connector for the alternator field.

You should consult the wiring diagram for the alternator to see what wiring is needed. You must run an electronic voltage regulator if you need one for the alternator with HEI type ignition or it will kill your ignition module or control unit. Mechanical regulators generate lots of static which is highly destructive to electronic ignition.

Dave

 

[CBODY67]

The "static" might come from the points in the alternator constantly cycling as the regulator does its thing?

 

[GoneLoco99]

Why do you need 100 amps?

please list your electrical acccessories, stock and added.

Other then the electric AutoMeter gauges (oil pressure, water temp, volt meter, fuel gauge) and HEI distributor just an after market stereo but nothing high tech.

 

[GoneLoco99]

The L shaped connector is for the Hot/Cold idiot lights. The loop connector was for the alternator output. The single straight black connector ran from the voltage regulator to the alternator field. If you are retaining the idiot lights, you can plug that lead back into the sensor on the intake manifold. You will need to replace the loop connector lead with a heavier wire. Depending on if your alternator needs a voltage regulator, you might need the straight black connector for the alternator field.

You should consult the wiring diagram for the alternator to see what wiring is needed. You must run an electronic voltage regulator if you need one for the alternator with HEI type ignition or it will kill your ignition module or control unit. Mechanical regulators generate lots of static which is highly destructive to electronic ignition.

Dave

Thank you very much!!!! Very helpful.
Much appreciated

 

[GoneLoco99]

This is the paper that came with the alternator.

 

[Davea Lux]

The one wire alternators do not use an external voltage regulator, so you do not need to worry about wiring a circuit for the regulator. This unit should be self activating so the only lead you will need is the #6 wire to the output lug.

Dave

 

[GoneLoco99]

The one wire alternators do no use an external voltage regulator, so you do not need to worry about wiring a circuit for the regulator. This unit should be self activating so the only lead you will need is the #6 wire to the output lug.

Dave

Great!!! Glad to here. Again thank you

 

[John Kirby]

If you don't want to bypass the ammeter you can mount one of these under the hood. Connect the alternator to it and any high demand loads. (stereo, fans, etc). This reduces the current through the ammeter from heavy loads.

It's not a good idea to connect high current loads to the battery, that will cause the ammeter to constantly have high current flowing through while they are active. It may burn it out.

The firewall connection for the alternator and battery barely handles the stock alternator as it is. Chryslers have these terminals burn out over time. The headlight connection is another problem area too.

If you look at the wiring diagram in the service manual the ammeter is mainly for monitoring battery charge current. If the battery is fully charged you can turn everything on with the engine running and there should be little current running through the ammeter if the alternator is doing it's job. I don't recommend blasting the stereo and fans with the engine off. If you do then all the current will be going through the ammeter.

My fan setup has an enable wire connected to the ignition on wire so it won't run when you turn the key off.