Yes, motorola alternator help!

Ok so this is what I've got. I installed a rebuilt motorola alternator, and was not sure about how to wire it up. A fellow jeeper sent me a picture of how his was wired so I wired mine based on his pictures. However, I've noticed that the alternator is not charging the battery. Here some pictures of how it is wired.
I'm looking for a diagram of how it should be wired.

Thanks in advance.





Two reds connected to the same post, two gray connected to the same post. It starts up and runs just fine. But I notice there is a post to the left that looks as if there should be a wire I connected to it since it has two nuts on the one post.

 

will this help

 

Yes I'm sure it will, I'm not sure if I should have both of those grey wires connected to the same post

 

My alternator is wired the same way as yours and has been working fine for 48 years. The two heavy wires (red) on the large stud should be only one which goes down to the battery stud on the starter solenoid unless you are using an ammeter. Why the two heavy red wires? Where the two grey wires are connected on the isolation diode plate there should be a fiber insulator washer between the red diode plate and the first nut. There should also be a insulator sleeve around the same small stud to isolate the stud completely from the red plate. There should also be a flat fiber washer insulator on the underside of the red plate at this same small stud.

 

The two red wires come out of the new wire harness labeled "alt" for alternator, I'm sure one of them runs down to the starter. So I'm correct on the gray wires. What about the stud on the left bottom of pictures? Is that for a ground? It has two nuts on it making
it look as if a wire should be connected there?

 

On the two red's, I see that is the option of the harness manufacturer. There are three options for the Batt connection to the ignition sw. Either back of alternator at Bat terminal or the starter solenoid or direct to battery POS terminal. The other stud at the bottom is another ground terminal. Not used. The other ground terminal is used by the Black/wh wire from the regulator as shown.

 

Thanks again Walt, I think I will disconnect one of those red wires and tape it back since I don't need both of them connected. We will see what this will do.

 

No you will need both of those heavy red wires connected just as they are. What I was saying was that the loom manu has three places to connect the main ignition supply and they chose the back of the alt for the BAT connection.

 

Ok, well I will just leave it like it is. It starts and runs fine, but the machenic I brought the jeep to said it looks like it's not charging the battary. If wires are hooked up correctly, not sure what the issue is.

 

You can easily full field the alt which will test the output of the alt and tell you if the regulator is working or not. Do you have a volt/ohm meter or a portable volt meter?

 

No I don't, and when it comes to the electrical it's all Greek to me, however, I'm sure I can get my hands on one, and I'm willing to learn.
So how do you full field the alt. to test it?
And i do have a brand new voltage regulator, but I do know that doesn't always means it works.

thanks

 

Twin2's post #2 shows the field terminal #5 on the picture. Pull the wire off this spade lug. Unplug the voltage regulator. Connect the volt meter, red lead to pos battery and black ground lead to engine ground. Make sure meter is switched to DCV. You will be looking for about 12.5 +/- battery voltage. Make up a jumper wire that will clip onto the field spade lug and BAT terminal on the back of the alt (2 big red wires) but leave one end not connected at this time. Start the engine and connect the jumper wire. Observe the voltmeter while revving the engine to about 12-1500 rpm. The meter should increase to 14-15VDC. If this is good then put the pos lead of the volt meter on the small stud on the red diode plate that has the two grey wires on it. You should read about 16 plus volt while the rpm is at about 12-1500. If this is good then remove the field jumper wire and shut down the engine. Connect the voltage regulator and the field wire to normal. Connect the voltmeter pos lead to the Bat terminal on the alt (should read battery voltage) and start the engine. Again at 12-1500rpm you should read a regulated 14.2-14.8VDC. If not then regulator is bad.

 

What ever happened? Did you get it resolved, how did you fix it?

Jon.

 

"If it ain't broke, don't fix it"

i sent you a PM Jon, check your in box.