chaikwa

I got the engine running and it seems close to perfect. I guess I gotta get lucky once in a while!

Anyways, now I'm trying to get the alternator to charge. I put a brand new alternator on it because the old one was frozen solid. (This is the style with the external voltage regulator) There are 2 wires coming from the alternator, (besides the big black power wire), one green, the other blue. The voltage regulator also has 2 wires, one green the other blue. When I hook them together in a color appropriate manner, I get no charging taking place. If I run the blue wire off the alternator to 12 volts positive, I get uncontrolled charging.

Is the regulator bad or do I need to run these wires in a different manner? Someone told me the green wire off the alternator goes to the voltage regulator and the blue goes to switched power, but that leavers me with the blue wire off the regulator with no place to go. That's also when I get uncontrolled charging.

Can someone offer some insight into this for me please?

thrashingcows

According to my 89 shop manual the green and blue wires should be connected together. The green one comes off the back of the alternator, and goes to the voltage regulator. Then the blue wire out of the voltage regulator goes to a splice...."J2". This splice has the ignition switch, heater control, vacuum sensor and "to left side engine wiring".

So I would think if you have uncontrolled charging then the voltage regulator might be shot?

chaikwa

So just to be clear, the green AND blue wires coming off the back of the alternator get tied together, then run to the green wire on the voltage regulator, and the blue wire from the voltage regulator goes to switched power?

Thanks for your reply! I'll try this tomorrow with a new VR.

torquefan

Not exactly. The two small wires on the alternator run the field winding. One must be hooked to a 12v ignition feed, while the other goes to the regulator, which controls the alternator's output by regulating the ground to the alternator's field winding.

On the regulator, one of the two pins gets hooked up to the alternator's field as mentioned, while the other pin needs to see 12 volts so it can monitor system voltage. The body of the regulator must be connected to ground in order for it to work.

My apologies, I know how the system works, but don't know which terminal is which off the top of my head.

torquefan

Here, this might help:

chaikwa

Thanks again! I'm going to get a new regulator and I'll get it all hooked up. I'll be back with the next question... um... I mean, I let you know how it all works out shortly!

chaikwa

torquefan, your instructions worked perfectly. It's charging at a consistent 14.7 volts. THANK YOU!

torquefan

Awesome, glad it worked out for ya! Good luck with the rest of the project, I'm looking forward to following along as you work on it.