charging problem

[BPH90LX]

I just upgraded to a 3G alternator and dont seem to be getting enough charge from it. I was already having a electrical problem where it wouldnt turn over except when jumped. It would stay running but wouldnt restart. I have changed out the battery, cables, and starter solenoid besides the alternator. I checked all the grounds and added a 4g ground from the block. The belt is tight and the 3g has a little smaller pulley the the old one. the battery shows 12.4v with the car off, 12v running, and dosen't go up any with RPM's. I also have the 4g power wire from the 3g to the solenoid and the B&w wire is hooked up, the black and orange's are not.
It starts and runs now but I'm thinking not for long without getting more volts, any ideas? Thanks

 

[HISSIN50]

If the wiring is sound, have you had the alt bench tested to make sure it's good?

It looks like you arent getting any output from the alt.

Good luck.

 

[302RollinHard]

Isn't there a pin (most of the time plastic) in some cases that is installed in the back of the alternator to retain the brushes during assembly?? This is a thought if the alternator is new or a fresh rebuild. Take a look. Or it could just be a dud.

 

[BPH90LX]

There was no pin holding the brushes in but I checked and dont have any power on the ignition switch wire. Does that mean it just needs replacing to get the alternator charging?

 

[HISSIN50]

Which ignition switch wire doesnt have power? I got an idea but wanted to ask first.

 

[Saleen0679]

The ignition switch is part of the regulator voltage control switching circuit so it could very well prevent the alternator from charging.

If you have multiple problems that involve the ignition switch like it sounds, it is inexpensive enough to eliminate by replacement if you don't want to spend the time troubleshooting.

 

[Skoobie]

Not sure whats going on but you should be getting more than 12v while running. I get 14.5-14.9 at idle. I think thats pretty much the norm. Either you have a bad connection or you got a semi-bum alt

 

[BPH90LX]

No power on the green & red off the alternator that connects to the B&W from the factory harness

 

[HISSIN50]

Saleen and I had the same thought.

If that red/green wire doesnt get power to the alternator, it wont charge. There is a ground circuit in the regulator. WHen the alt is not charging, the reg creates a ground for the far end of that red/grn wire (this ground allows the battery light to come on). WHen the alt is doing fine, the ground dissipates and the light goes out.

There is also a resistor in the circuit for the event that the battery light bulb burns out.

Saleen can probably explain a whole lot more coherantly than I can.

Good luck.

 

[BPH90LX]

IThe battery light never comes on, even when starting so I have a new ignition switch on the way. I hope that fixes it.

 

[BPH90LX]

The ignition switch was the problem, its charging now. Thanks