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This is actually for my 47 cj2a 'heep'.

It was converted to 12v alternator with voltage regulator before I got it, and I decided to keep that superior system.

I have F on regulator hooked to F on alternator.
I have 2 on regulator hooked to R on alternator.
I have 3 and 4 tied together and hooked to the coil, or somewhere in the positive side (I have moved it, currently in the fuse box now - was on coil +).

4 is the exciter and 3 is the voltage tap - supposed to tell the thing when to lay off the charging if I remember correctly.

The problem is, that the alternator seems to be putting power back into the electrical system and so when I have the 3/4 wire on, the alternator backs up power into the system and so the engine doesn't cut off.

So...what do I do with them wires? Or is it an alternator problem with it putting out a charge on the F/R wires? Or is it that the voltage regulator is dumping power out? I could eliminate wire 3, seen that before.

I have rewired the whole heep and have the positive from battery going into the ignition switch, which turns on everything. And there ain't much there other than lights and engine.

Thanks - and that's why you haven't seen me posting much lately as I have been traveling for work, and when not traveling, working on the jeep. As for the 59 - well - it just goes and goes and goes...

You're going to need a resistor wired into the system that won't allow enough current to back up and supply the ignition, while still leaking enough voltage to operate the regulator. That's a pretty common problem when you don't have an idiot light in the circuit. The light acted as the resistor on the older remote-regulator systems. The ones with an ammeter used a resistor in place of the light.
why not upgrade to a self-regulated alternator, and eliminate the separate regulator? They're considerably higher capacity, too.
Jerry

Here is a simplified diagram of your charging system. Why not just add a charge light? It will get your attention when you throw a belt before your engine heats up.

[img]http://www.rowand.net/Shop/Tech/images/AlternatorWiringOverview-1963to1972Buick.jpg[/img]
#3 is the voltage sensing wire and is wired as shown. #4 is the exciter wire and is switched off by the ign. switch. The resistor and light can be tied together at the ign. or the resistor used by itself at ign.

I borrowed the same drawing because it's the best one around.

Thanks, that ought to do it.

Ok, here is where I am now.

I have followed the diagram above to the letter except for the resistance wire from 4 on the regulator to the accessory pole on ignition switch.

If I have the sense wire (3) on current backs up into the system and keeps the jeep running and lights up the tail lights. That is, when the jeep is running, it stays running if wire 3 is on battery positive, and its a brand new regulator. The good news is that the alternator charges.

If I take wire 3 off, there is no charging, but the ignition switch turns the vehicle off and the brake lights are not on.

Suggestions?

I have an indicator light added to a stray hole on the jeep's dashboard hooked to ignition through a fuse box. That is power goes from ignition switch to a fuse box, through a fuse, to the light, to the 4 post on the regulator.

The charging light goes out if the sense wire (3) is connected to battery positive and the system charges. If the Sense wire (3) is off then the charging light is on and there is no charging.

The tail lights do not light up with the sense wire (3) on or off if the jeep is not running. They come on when the alternator is charging and stay on if the sense wire is connected to battyer positive.

I know the system is charging because the ammeter reads in the positive and the battery voltage increases.

I think I have anticipated all questions, other than, what am I doin rong???

Since the system is so simple, I am thinking maybe its the alternator and some how current's backing up through it, but I am not sure as I don't know the whole thing backwards and forwards.

On my yard dog I have the same set-up without the wire to the accessory terminal (I have no accessories), and mine works fine so the lack of that wire is not the problem. I don't understand how the tail lights got into the equation but I'd suspect that is the problem. Nothing should be feeding to the tail lights from the charging or ignition systems. I'd start by trying to find what is feeding them. They should be fed only from the light switch.

Right Cletis. I hear you.

Since the alternator exciter wire is hooked after the switch, and the alternator power is before the switch, as well as the sense wire, I have to think that power (once in charge mode) is coming back through the exciter wire. But only when the sense wire is hooked up.

I have retrieved an old alternator that I had as a spare and I think I will hook that into the circuit and see if the behavior is differnt. I am thinking that once the alternator is energized, then it backs up power through the circuit.

Only the alternator exciter (which is switched, and the only part of the system after the switch) can be putting current back into the circuit and powering up the tail lights. The tail lights get power from the fuse box, through the light circuit. Power goes from the fuse box to the headlight switch to the tail lights, and from the fuse box to the brake light switch to the tail lights.

I guess what I should test next is hook the system up for charge, then see if hitting the brakes lights up more lights. I'll have to do with the garage partially closed, so it will have to be a quick test so I don't gas myself!

Blech.

I had a similar charging system problem on an old motorcycle such that when things weren't working right, the system would energize the lights. I suppose I could also see if the headlights are trying to come on and that might also tell me another part of the equation.

Power goes from fuse box directly to headlight switch (new) which then distributes power to the park lights and tail lights, and when all the way out, to the head lights.

Then again, if that is all true, a diode on the exciter wire such that power could go only to the regulator and not the other way should solve the problem. So maybe its an open diode in the alternator?

except for ?
Do you see any fuse box on the wiring diagram????

Aside from all of that.
Pull the plug off of the regulator. The flat spade connectors are F, 2, 3, 4, from left to right. By any chance is #2 missing? If it is there, good. Then put an ohm meter across pins 3 and 4. It should read infinity (open). Any other reading is unacceptable.


In reference to the above: Run one wire from #4 to the indicator light and then, on to the ign switch. IF. If the alternator doesn't start charging and the light go out, without revving the motor then add the resistor in parallel with the light. As I tried to explain earlier, forget about the ACC connection.

The problem is that I stoopid.

I had the ammeter after the ignition switch instead of BEFORE as I had assumed. Since the alternator was connected to that, it charged the system, as it was supposed to.

I thought I had it the other way around and everything else I had done assumed that. When I put a diode on the only wire that was after the ignition switch, and the thing ran on, then I knew I was stoopid.

Oh well. At least I figured it out. I was rewiring the thing while working from home on various support issues and obviously got confused.

I stoopid. But at least I figured it out and fixed it. It works as designed now.

DOH!

BTW, a 1947 jeep doesn't have a fuse box, I decided to modernize stuff a bit. Power goes from battery/alt to ammeter then to ignition switch, then to fuse box and load distribution.