Switching from a generator to an alternator, how to wire it.

[Grouser]

I've got one post on the back of the alternator. It says battery. Do I tie it into the wire that comes from the amp meter to the battery terminal of the old voltage regulator, and go to the battery with them both or what? Thanks for your help I hate wiring.

[LarrBeard]

You did not say, but I am assuming that you are doing a 6-volt to 12-volt conversion.

One of the first questions I would have to ask is “What size is the alternator, how many amps?” If you are adding a 100-amp alternator, the alternator can provide much more current than most stock Jeep ammeters- which stopped at about 50-amps. The ammeter should only have to handle battery charging current, but it’s just not nice to tempt the lightning gods with underrated parts. You’ll probably end up changing the original ammeter or, as many folks do, changing to a voltmeter.

The new alternator should have had some installation instructions with it, showing how to wire it with an ammeter or an idiot light. Mr. Google has a lot of examples of how to wire this. Wiring is really just about as simple as adding one wire from the BAT post on the alternator to the + post of the battery. I would tie the alternator directly to the + battery post - not to the old BAT terminal on the regulator. The alternator has an internal regulator. The old regulator is not needed now – and you will have the FLD and BAT wires left over.

Use heavy enough wire from the alternator to the battery + terminal to handle the output of the new alternator. Don’t scrimp – I’d go with at least #6 stranded wire. While the alternator case is return (ground), I’d also add another #6 from a mounting bolt to a good chassis ground.

Lights and instruments will need to be changed over to 12-volts, so will the coil. Changing over to a 12-volt starter is a 50/50 proposition. About half the folks make the change, half don’t. Make sure to add a fuse or circuit breaker block somewhere. The upgrade to the electrical system is adding enough power capacity to hurt things if something goes wrong.

Let us know how it goes and show us some pictures of the project.

[Grouser]

That's a good reads err! Thank you very much for your simplistic clarity. I am going from 6 volts to 12 volts and this alternator is a used one so I didn't have the instructions. Your instructions were very helpful in review I only have one question. The wire coming off the amp meter, I think it feeds power to the instrument panel, used to run to the battery terminal on the voltage regulator. Where do I run that one? To the battery? Thank you again for your help sir here's a few pictures

[bmorgil]

Grouser, do you have a wiring diagram?

http://www.ewillys.com/2013/01/01/wiring-schematics/

It will hook up very similar. The BATT terminal on the alternator is the "Charge Line" so to speak It will carry the high amp output. That wire goes to the plus side of the Ammeter or, the Regulator depending on what you have. The neg side of the ammeter should have the BATT line from the Starter/Battery. Wire size is important as Larry Beard has warned.

http://www.aic-controls.com/wire-sizeis

The #6 Larry suggested, is what I ran. I have a 65 amp 1 Wire alternator. You will need terminal ends that fit the wire and the ammeter/alternator/regulator. You did not mention what type of voltage regulator you are using. As Larry suggested you will need to Google the hook up so it regulates correctly. In my case it is a one wire GM 10si and internally regulated. I only had to hook up a charge line to the Ammeter.

[LarrBeard]

That's a good reads err! Thank you very much for your simplistic clarity. I am going from 6 volts to 12 volts and this alternator is a used one so I didn't have the instructions. Your instructions were very helpful in review I only have one question. The wire coming off the amp meter, I think it feeds power to the instrument panel, used to run to the battery terminal on the voltage regulator. Where do I run that one? To the battery? Thank you again for your help sir here's a few pictures

Here is a link to a way to keep the ammeter with the new alternator.

https://www.google.com/search?q=1+wire+alternator+with+ammeter&tbm=isch&source=iu&ictx=1&fir=hU5dbnEEmz4zGM%253A%252COY2i8WvHcpaDLM%252C_&vet=1&usg=AI4_-kQMDZnUv-U6-Iqxa8OY6KDt67YgEw&sa=X&ved=2ahUKEwiY6sOsmunjAhXBGc0KHd9_A34Q9QEwA3oECAcQB g#imgrc=hU5dbnEEmz4zGM:&vet=1

[bmorgil]

Grouser do you have a wiring diagram? It will wire up very similar.

http://www.ewillys.com/2013/01/01/wiring-schematics/

Wire size is important as Larry has warned.

https://www.cerrowire.com/products/resources/tables-calculators/ampacity-charts/

You do not mention your voltage regulator. What one will you be using? You will need to find a schematic for the regulator you will be using. Basically the BATT terminal on the Alt is the CHARGE line. It needs to go to the regulator or, if you have a one wire alternator, to the plus side of the ammeter.

https://www.thecj2apage.com/forums/12v-wiring-diagram_topic19145.html

I use a "1 wire" alternator on everything I have. With it you run one wire from the Batt terminal to the Plus side of the ammeter.

[Grouser]

head hurting a bit now..thsnks fire the help! So to review what you said I need to take the single wire from this alternator and run it to the positive post of the ammeter and then a wire from the negative post of the ammeter to the positive post of the battery. Correct?

[LarrBeard]

head hurting a bit now..thsnks fire the help! So to review what you said I need to take the single wire from this alternator and run it to the positive post of the ammeter and then a wire from the negative post of the ammeter to the positive post of the battery. Correct?

CORRECT!

Plus - more than you want to know..

Positive (+) terminal of ammeter goes to the ignition switch or to the big terminal on the circuit breaker that is often located on the light switch.

Another BIG cable goes from the battery (+) terminal to the big high current stud on the starter or solenoid.

You don't have to worry about a voltage regulator any more- the alternator has its own internal regulator.

[bmorgil]

head hurting a bit now..thsnks fire the help! So to review what you said I need to take the single wire from this alternator and run it to the positive post of the ammeter and then a wire from the negative post of the ammeter to the positive post of the battery. Correct?

As LarrBeard said, you got it! PROVIDING you have a one wire alternator. If there is a small plug on it to hook up more wires... it is not a one wire. The term "One Wire Alternator" really means it is an internally regulated "self exciting" alternator. At a given RPM it kicks on by itself. Most alternators require some form of "trigger" to get them to begin charging even if the regulator is internal. Is this alternator off of a vehicle or, did you purchase it new? Take a picture or two of it if you are not sure what it is. One Wire alternators are typically made by using an internally regulated alternator and, hooking it up to itself so to speak. As it spins up and generates voltage, it provides itself the "trigger" to begin charging. So, the plug for the other wires will be empty on the back of the alternator.

Sorry if this is TMI! It's hard to tell what you have going on via the keypad.

[Grouser]

It's definitely a single wire alternator, there's only one Post in the back. I know what you're saying about the clip and multiple wires on the others. This was taken from another Parts jeep that I got so I don't have any real information on it and I do have wiring diagrams. But to be honest I can find things in the diagram that I don't understand or aren't clear to me. I really appreciate you guys's help have a good day

[bmorgil]

No problem Grouser, we can get you through this one. I put in a few pics in case someone needs to see a one wire alternator. Note the black plug covering the external wire hook ups. This is a converted GM 10SI. It energizes at 800 rpm.