Alternator Fault

You will need to check the yellow (hope that is the right one) wire going to the regulator to see if you have voltage when the ignition is on. If you have no voltage the regulator will not "turn on" on the alternator will not charge the battery. I would also check to make sure the regulator is mounted and "grounded" or the same this will happen.

Yeah, check all of your wiring, maybe some melted and are touching?

Red 72, if you have regular gauges/lights(not a performance cluster with tach) you should have a green wire w/ red stripe going to the "I" terminal of the voltage regulator. When the ignition is switched on there should be battery voltage on this wire/"I" terminal. If you have the performance cluster, when the ignition is on you should have battery voltage on the "S" terminal of the voltage regulator, also uses the same green w/red stripe wire. The yellow wire should have battery voltage at all times like you previously found. Here are some images that may help.


Hopefully these will assist you in finding your problem. Todd

Edited by aquartlow - 12-January-2014 at 1:11AM

Adrian,
First, a few ?'s. Do you have an ammeter gauge or light? Is there 12volts on the "S" terminal with the ignition switch on, or all the time? Have you found the green/red stripe wire and which terminal was it connected to? Is the VR(voltage regulator) grounded good, the VR's body is grounded when you install the two mounting bolts/screws. When you check for voltage at the VR plug, what terminals have power with ignition on and when the ignition if off? Make sure you have a good ground wire from battery to engine block, make sure the alternator is grounded good(may want to have a dedicated ground wire attached to the rear of the alternator's case instead of relying on the large bolt and spacer to make up the ground path for the alternator to the engine block). I realize electrical bugs are sometimes a real pain, but it usually boils down to something simple and/or overlooked. Good luck and keep us posted. Todd

Edited by aquartlow - 14-January-2014 at 12:54PM

Dan the ranchero man wrote: Helpful hint: If you are/have restored a car and have "painted evrything" Make sure that the paint in not insulating your grounds (i.e. voltage regulator body) Been there done that!   Todd: Thanks for pointing out the right color wire for the VR switched connection. Been a while since I have had to check one. Dan

Dan,
You are very welcome, always glad to help if possible. Good tip on the paint, I have been guilty of doing that.....once . BTW, how is that little PMGR starter working out for you? Todd

Well found the fault. It was the wire to the  "S" terminal was braking down so I jumped a wire across from the battery and it started charging.Will it be ok to run a wire strait from the ignition switch to the  "S" terminal .

Thanks for all your help Todd.