Alternator not charging -UPDATED-

[oddball]

It does have power, the only one of the three wires that didnt was the field which seems to be a ground

[oddball]

The regulator has 3 wires, the first picture is what I believe to be the original plug. I replaced the whole charging harness with one that looked similar except for the wire colors, that is in the second picture. I dont recall seeing the field relay anywere though. I will take more pictures tomorrow and post them in the evening if it helps

[Thunderfoot]

Ok looking at the plug you have there, you probably don't have the one with the "Field Relay" but you ARE missing the exiter wire connection in both of those pictures... It would go on the "end" that doesn't have a wire in it. I will try to get a picture of mine tomorrow to show you see what it should look like.
Edit: you might also get a picture of what you have just to be sure.

[oddball]

That would be great, I really appreciate all the help.

[JMcTurnan]

The only thing I can say is try a new voltage regulator, dont redneck test the alternator by pulling of neg battery cable while it's running, because it shorts the regulator. Possibly a new battery, or it isnt properly grounded.

[oddball]

Ive tried three different regulators, two of them new. The battery is new and the grounds are fine. I might try a new regulator again and see because I simply can not find any other problem. The black wire that I thought was the exciter was just stuffed up away with electrical tape on it (first picture), so I have no idea what that is for. There are three wires going into the regulator, green/red stripe, yellow and orange. Yellow is constant power, orange (field) has no power. The green/red stripe has power with key on. I traced it to behind the instrument panel were it splices into a red/ green stripe wire that goes to the ignition switch. That has to be the exciter right?

[BigRed69]

I feel for you, I just bought a '69 F-250 and am having the same problem with my alternator charging, but mine charges intermittently, I hope it is just a weak alternator, if replacing that doesn't work, I will be looking for help as well. Good luck, I hope you figure it out.

[Thunderfoot]

Well… I seem to have some issues on my understanding of the Voltage Regulator wiring on our trucks… I checked BOTH of my trucks (one has Amp gauge and the other has Idiot light) and they both only have the 3 wire terminals used (F,S, and A) they don’t have anything wired to (I) but this is the one that every wire diagram I have found shows as the “Exciter Wire” to the ignition switch… (see other picts below that I have found) plus descriptions as follows.

F terminal on the regulator connects to the field connection on the alt.
S terminal on the regulator connects to the stator connection on alt.
A terminal on the regulator connects to the battery +( Plus) or positive terminal. (senses voltage of battery)
I terminal on the regulator connects to the ignition switch. (turns regulator off & on)

So from what I see it looks like the Exciter wire is connected to the “S” terminal… but I would need to do more checking with a meter to trace this wire down more on my truck… That may be a while as it has been too cold to work outside and is snowing again.

But a couple other things you may try; is making sure the Voltage Regulator is grounded good to the core support AND has a wire from one of the mounting bolts to the Alternator ground terminal (G) (like the one in my picture below).
The other would be to take the Alternator out to the parts store and have them check it out again… or you can do a quick test yourself by unplugging the connector from the voltage Regulator, then jumper a wire between the “F” wire and the “A” wire (this should have 12v on it from the battery. This will force the Alternator to charge FULL output so don’t do this for any longer then just to check that the alternator is putting out voltage over 14.5 (Usually Higher so it could cook your battery or Alternator if run it too long this way! (this is a procedure written in ford manuals to test the alternator on the car)

Sorry I’m not better help here as this missing “I” wire connection has me baffled and I will be doing some more research on it, but it looks to be normal for our trucks.

1G-ALT_wiring.gif

69_truck_Voltage_Reg.JPG

[oddball]

Haha I know what you mean, the more I pick around at the wiring the more baffled I get. I always thought that the "I" terminal was only used for trucks with the idiot light. Ive never seen one personaly. Most of the trucks with ammeter gauges that Ive seen at least until 69, use only three of the four terminals on the voltage regulator.I really appreciate your help. In the meantime Im going to see about trying another voltage regulator

[oddball]

Here is a picture of the VR connected. Sorry its a bad picture. I took all the wire wrap off just to make sure there wasnt any cut or extra wires in the harness. All the wires look good, unmolested and accounted for.

[oddball]

Well I fixed it, I bought a 4th regulator and that did it. Thank you to every one that helped out.

[fordman]

i'm glad it wasn't something wierd wrong with it. or hard to find.

[Thunderfoot]

Glad you got it fixed and working sucks that you had to go through 4 regulators to get a good one

[oddball]

Thanks again for your help, Im not miffed so much about the regulators as I am about tearing into the wiring and pulling the rest of my hair out for the last month.