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I bought a 52 convertible recently and have driven it around a bit, but I believe that the charging system is not charging at all. The idiot light does not go on under any circumstances and i began to notice a slow turn over after driving the car.

I started it and, with about 2000 RPM, disconnected the battery and the car dies.

The Voltage regultor looks like it is pretty new (all the wiring was redone prior to purchase, but it looks quite prfessional and all in the proper wire). No indication of burnt points, etc. But, when it comes to electrical, I really am lost. I did the test of the closing voltage of the circuit breaker described in the manual, but the needle does not move at all at any RPM (no voltage passing through). Tried it a few times with a couple different voltmeters.

I would like to go systematically through and test that the wiring going to the VR is delivering voltage when and where it should, then test different components of the system.

Is there a guide somewhere that can help me to test that the basics are in place. I can just buy another Voltage Regultor and hook it up, but I am not sure this is the issue.

Any help in steering me in the right direction is apprecialted.

Simple test, back to basics. With the engine running at fast idle and a voltmeter on the battery, note the voltage. Then temporarily use a short jumper wire attached to the Field (F) terminal of the regulator and ground it. If the battery voltage increases, the generator is OK and the fault lies with the regulator. If the voltage doesn't increase, the generator is at fault.

G'day Jim,

Congratulations on your '52 Convertible Coupe. And I invite you to include it alongside your '41 120 Touring Sedan in the Packard Owner's Registry.

Another simple test of a generator: connect 6volts to it with polarity correct (+ve earth) and it should 'motor'. That will mean wiring is generally ok and brushes / commutator are in working condition. But output is not guaranteed to be good using this test.

Might also be worthwhile to ensure the generator field is polarised correctly, as per Electrical Section of the Service Manual (page 7). Very briefly connect a jumper lead between the 'A' and 'B' terminals of the regulator to achieve this.

Grounding the Field terminal did not affect the voltage at all, so I will pull the generator and replace the brushes to see if that does it.
I spend about 1/2 my time in China, so I don't have many weekends to work on the car. But, plenty of time to order parts. It will probably be mid-March before I have a go at this.
One thing I noticed as I was trying to figure this out. My regulator terminals are F, Gen, Batt going from driver to passenger side. The ones I see on line that purport to fit my car seem to go from Batt, F, Gen. Not sure why this is or which is correct?
I frankly do not remember if this system ever worked, I got the car just as I began my gig in China and it literally sat is storage for a year before I could touch it. Then six months doing brakes, wheel bearings, ...
It came with an 8 volt battery, grounded negative (which I assumed was incorrect). I put in a dry cell as they have been pretty bullet proof in my cars. I did hook it up positive ground, but my understanding is that there is not much in the charging system that really cares.
Now I wonder if it has actually been changed to Neg ground (what would that entail) and is there a way to tell. The radio does not, and never, worked even with the 8V in the car. Everything else (except of course the charging system) seems to work fine.
Can this be causing my current problem?

If the regulator was changed (and adjusted) for the 8v battery it could be the wrong regulator now and probably voltage is set too high and could damage your new battery. Some regulators are also polarity specific so that needs to be looked into. The terminal order is not really written in stone so can be different depending on mfg or model.

If the car was neg ground and you have corrected it then chances are the generator is now polarized incorrectly. Once the regulator is verified, redo polarization. With everything turned off but connected use a decent sized jumper wire to briefly touch the Bat and Gen terminals together at the regulator. Only needs a second or so and you will get a small spark as the two terminals are connected. It won't hurt and might help. A procedure that is recommended any time a regulator or generator is changed or worked on.

In a stock car nothing will have been damaged with the reversed polarity. If the radio vibrator was changed at some point to the solid state replacements available today and was for a specific polarity then it could be damaged -- or anything else that might be solid state such as any regulators that might have been added to take care of instrument voltage needs.

If it still doesn't charge after repolarizing then time to tear things apart.

I was home briefly for Saturday, so I had time to run down and try polarizing the generator. Tried the test suggested by Owen and I see no difference when grounding the F terminal.
Is there a way to test the generator while in the car? I want to make sure this is not a wiring issue if some kind.
I have a wiring diagram on the way, which will help next time I am in town.

Good Morning to you in Irvine or China...Since you are in Irvine when playing with your Packard, a quick trip up the road to Santa Ana, Custom Auto is at Third and French and have been restoring Packards for about 40 years in that location. I'm sure they would check the generator for you if you took it to them. They could also see to the repair and provide advice. The phone number is 714-543-2980. The shop is owned by Robert Escalante. He is a really nice guy.

Ernie, caretaker of 'Miss Prudence' a 1949 288 Deluxe

O_D's test is the best simple way in the car. By grounding the field wire, that bypasses the regulator and makes the generator put out the max voltage. If you don't see a voltage jump at the battery from approx 6.3 to something well over 7 volts as the field wire is shorted you can assume the generator is not functioning. If you do see a voltage jump then that would tend to narrow the issue to the regulator. The next test would be current output. For that you would need some test equipment capable of reading a much higher amperage than the typical homeowner Volt/ohm meter can handle so probably need a shop.

Even w/o the test equipment HH56 recommends (best way), you can still get a reasonable measure of the generator output in amps, once you have ascertained that the generator works and have addressed the faulty regulator, if that was the issue.

Simple, start the car, turn on the headlights, heater and any other electrical accessories, increase the engine speed and watch your dashboard ammeter. If the gauge shows anything on the positive side (charge side), your generator output is at the least, adequate.