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The first step in analyzing a no-charge situation should be to determine if the problem is with thr generator or the regulator, and this is most easily done if your car has an ammeter. With the engine running, just temporarily ground the FLD terminal at the regulator or generator. If the generator now shows a large charge (or if the battery voltage goes up if you don't have an ammeter) the generator is OK and the regulator is at fault. If it shows no charge, the problem is with the generator. Do not leave the field grounded any longer than needed to make the determination.

As to the generator "motoring" when you close the cutout points, that's why the cutout function is there in the first place. When the generator voltage is higher than the battery, the cutout closes and current flows to thre battery. When the generator stops running, the points open and disconnect the generator from the system.

Thanks O_D! I'll try that first thing tomorrow. Do you know what regulator I would need to replace mine if I want to keep the negative (-) ground? I have a couple accessories, like my tach, that require negative ground.

Do you know what regulator I would need to replace mine if I want to keep the negative (-) ground?

No, I don't, not a clue. I've been told there are regulators that are not polarity-sensitive but don't know more. Yours is a good question for Jason at AER.

I'm unfamiliar with AER, do you have contact info?

I found a couple regulators for sale for decent prices, might just go back to pos. ground. The wires on the coil need to be flipped, correct? Coil (+) to dist., coil (-) to hot?

I'm unfamiliar with AER, do you have contact info?

Jason is an occasional visitor to this site.

Advanced Electrical Rebuilders
jason@aerrebuild.com
www.aerrebuild.com
Specialist in Starter, Generator, Distributor & D.C. Motor Restoration

i highly recommend Jason.

So I put my system back to positive (+) ground. Still no go, but now my gen. makes a whirring sound like a supercharger when the engine is running, and still no output. None of the points in the regulator move at all, so I know it must be fried, but when I ground the field terminal I still get no charge... I polarized it by jumping the battery negative (-) to Arm. terminal on the gen. I tested continuity of the wiring to verify thats not the problem, and here's what I found: Field terminal has continuity with field, arm, and ground. This seems wrong, is this caused by the voltage regulator not functioning?

Quote:

Not wrong. Here's a simplified drawing of the generator circuit from the V8 manual. Everything is more or less tied together -- either directly or thru other parts.

If you measure the Field terminal, it indirectly connects to ground no matter where you measure it. Measuring generator only it reads thru the coils and armature to ground. Measuring at regulator, it reads thru low ohm resistors or closed contacts to ground. Same with the field to armature. At generator, thru the coils. At regulator, thru a resistor and the coil windings in the regulator.

Unless you have very sensitive measuring equipment, it would be hard to separate things out with readings from a typical ohmmeter.

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Thanks for the diagram! I also found that because of my new cooper plug wires, my digital meter goes crazy when its too close to them. I made up some extra long leads so the meter can be well away from the engine compartment and it gives far more accurate readings now.

Today I tested the gen to be sure its putting out voltage. With the wires to the regulator removed, I grounded the field terminal to the case, and tested for voltage at the arm terminal. This gen is capable of producing well over 20volts (my meter went blank in the 20v range). Is this normal for a 6 volt gen? I also observed the regulator with the cover off will running the engine (wires all hooked back up) and there is no movement at any engine speed. I think It's safe to say its the VR that is the culprit. Is there anything that can be done to repair them beyond polishing the contacts? I ask because my neighbor restores vintage RC boats and repairs the old servos and what not, but I don't want to bug him if its a lost cause.. I know that's a pretty far stretch, but you never now if you don't ask..

I also am pretty sure the whine from the gen. is just the bearings. It makes the same noise even when the wires are all disconnected. I'll see if a good squirt of oil I'm the service port helps with that.

Removing the generator control and battery from the circuit will produce voltages such as you measured, I'm not sure why anyone would knowingly ever do this. If you want to measure voltage (but measuring amperage is much more meaningful), reconnect everything and measure voltage at the battery both static and with engine running at fast idle. A good battery in static condition (no load, engine not running) should be 6.4 volts; with the generator functioning and an electrical load applied (like, turn on the headlights) you should get about 7.2 volts. If with the engine running you still get about 6.4 volts, do as recommended earlier and temporarily jump the FLD terminal to ground. If the voltage doesn't go up (or the lights brighten), either the generator is dead or the cutout points in the regulator aren't functioning. To check for the latter, just push them closed with you finger and evaluate again.