Alternator question?

Here are the pics of the alternator and the voltage regulator





On the back picture, the 6 o'clock is the field correct? (spade connector), the 9 o'clock is ground and the 3 o'clock is aux (goes to amp light on dash?)

Walt, can you tell which alternator this is?

 

Ir is the Motorola for sure. The white wire should go on the small stud on the black plate that has the white insulator under the nut.

 

White wire (from voltage regulator) goes to the 10:30 position, is this where the amp light wire also goes? Nothing goes on the stud at the 3:00 position?

 

Isn't that rectangular beastie at the 6 O'clock position a voltage regulator?

 

Focker, your amp light and external regulator are the grey wires, field is green, battery is red and ground is black w/white tracer?

 

Motorola did make it confusing for sure. Orange cj5 is the stud at 3 O'clock insulated from the case? I cant tell from the picture. Focker you may not have the same alternator. If your diode plate has only one diode then it is a 35 amp (not 55) and your connections may very well be different. 1960willyscj5 the rectangular piece at 6 O'clock is a fiber board used as an insulator and dust cover. Orangecj5 the duo-diode (black) plate usually indicates 55 amp alternator. The white or grey wire from the regulator and the wire from the ind light will share the same connection.

 

Walt, I am not by the alternator right now but I think the 3:00 stud is NOT insulated from the case, but if I remember right both studs coming through the black bracket are insulated from the case.

 

Ok. From what I could tell it is just another ground stud. Now the two smaller studs on the isolation plate (black) could very well have been insulated from the black plate but only one stud will be connected to the diode trio (inside the alternator). Usually the small studs will have one longer than the other. The longer one should be the one for the 2 white wires. If that don't fix it then try the other small stud. You won't damage anything doing this. The are both at output potential except the diode trio one will be about 1.5vdc higher. That's the voltage difference that turns out the light.

 

Walt, here are some more pics of the alternator, I will have some time this afternoon to put it back together.



Do these show you which stud I should have the white wire on?

 

Meter.

Both of those posts look like the shakeproof washer is contacting the case. If they are, they are both grounded to the case.

I looked at the '74 manual for the Motorola alternator and the design is different from the one you have. I expect you need to go to the FSM to see which wires connect where.

My feeling is that 3 of the 5 posts gound to the case. There is the central post on the diode plate to the red wire, and there is one of the posts on the diode plate that has a fiber washer insulating it from the case. I'd guess that's the connection to your white wire.

 

I still say the above quote is correct. The terminal at three O'clock is the same ground as at 9 O'clock. The white insulator stud on the black plate should have both grey (or white) wires connected to it.

 

I followed Fockers advice and found that how it's wired in the pictures is correct. That's also how the guy at the alternator shop wired it to run the tests...

So: Alternator installed, wires run, connections triple-checked, belt tight (can't move fan by hand). Amp light is still on while Jeep is running. Turned on lights and heater to "excite" the alternator, no love. ~12.5 volts across the + and - terminals on the battery while it's running. ~1.6 volts from the post with the white and grey wires. What am I missing? Do you guys want pics of anything?

 

You realize that the regulator reacts to the battery voltage to enable the alternator? If the regulator does not send voltage to the field coils in the rotor, the alternator produces no juice.

 

This issue is fully resolved. Verified with the multi-meter five minutes ago.

I had replaced the bulb in the AMP light socket with an LED bulb, it appears that the draw from the LED bulb wasn't enough to "excite" the alternator, the battery measured about 12.5 volts across the terminals when the jeep was running. I swapped out the LED bulb for a standard bulb and the voltage across the battery when running jumped up to between 13.8 and 14.1 volts.

Thanks everyone for all your help. I truly appreciate this forum!