Alternator troubleshooting

Are alternators HAMB friendly?

Anyway, I've got a reman delco 12SI alternator for one of my projects and i'm getting no output. It's hooked up correctly, just not outputting. Due to circumstances, I can't return the alternator and i'd like to not have to pay for another one. Any tips on actually testing a troubleshooting the internals of an alternator? I don't have a problem buying a new regulator or rectifier, but I want to know how to test them before I go shotgunning parts at it.

 

You should find what you need here.Make sure you scroll down the whole page....
http://jeep.zerok.ru/index.php?page=39

 

What Themoose posted is about as good as it gets. Mark the case before you pop it apart though as you want it to clock the same way when you go back as you have it unless you would rather have it clocked different.

The first thing I would look for is something not connected or something missing. If you had it apart for one reason or another you did pull the pin that you held the brushes in out before running it? I've seen that happen when a guy had one apart and got distracted when he was bolting it back together.

 

have you checked it with a VOM meter.

 

Good lord i was just looking for this. thanks alot guys!

I have an SI style too. when the car is off (battery switch on) the alternator gets warm
I'm lost... I'll read up on this
My "Gen" light is on too.

thanks again

 

Make sure the exciter wire that runs to the alternator does not have power with key off. Had this problem and the alternator would be hot to the touch with key off.

 

Ya know what? Its got a jumper from the main stud(positive) to the exciter spade the one right next to the regulator spade. So yea it would be always hot to it...oppsss. hope I didn't mess it up.
How should it be wired? Ill take a picture today.
thanks

 

There a wiring diagram that came with my new Alt.

It shows the the 2 prong plug on the back
"1" gets 12 volt power from the key on/off
"2" gets constant 12 volt from the battery
and the output post goes directly to the battery also there is a post for ground on this model.

I am getting the tiniest little spark when I connect my battery cables, i mean little bitty spark, I unplug the 2 prong connector and the spark goes away. Any thoughts?
This is a remann alternator and is brand new out of the box today.

Thanks
Godspeed
MrC.

 

I think your ok with the light spark.

 

easy test: with vehicle running take a screwdriver and touch the backside of alt. in the center and see if you have magnetic draw, if their is one alt. is ok and you have wiring issue, if not alt. is bad.

 

ok, thanks, alot.

Godspeed
MrC.

 

Hey, themoose, thanks for that link. That will help a lot of people. Me included.

 

did you check alt for magnetic draw with engine running?

 

What the 55dude said, use a piece of steel and hold it to the rear bearing at the back of the alt. if it pulls like a magnet, it's putting out.

 

Great alternator article Moose posted. I went to troubleshoot a sudden dead battery issue yesterday. Put my DVM on 10 amp setting, disconnected positive terminal, one probe on terminal, one on cable. Dead short, or at least over 10 amps. Disconnected Bat terminal at alternator, short gone. It had sat for awhile with battery hooked up, battery now toast, fails load test (still charges to 12.5v but won't even turn on lights). Putting in new battery tomorrow. Suspect a shorted alternator. Never had that happen before..