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MY 32 903 Packard appears not to be charging the battery. I went on a 1/2 drive today turned it off and the engine would barely turn over. I came home after getting a jump and it again wouldn't restart.

I charged the batter and the engine turned over quickly and started. The ammeter shows discharging when I turn the key on. When I start the engine and rev the engine it goes to 10A charging. The voltage when I rev the engine on the battery climbs about .2V. I was assuming that the ammeter showing 10A charging would mean the battery was charging but it appears not. I have checked all the connections they are clean and tight.

Not sure how to go about troubleshooting this charging issue and how to determine if the battery is charging. I have a VR755 regulator.

Thanks ahead of time for the help.

Of course you should get a small discharge on just turning on the ignition key, that reflects the current draw of the coil - should be about 3 amps or so. More than that indicates something abnormal, perhaps a short in something that's wired to the ignition switch (heater blower, radio, etc.).

A 10 amp charging rate with the VR755 is normal if you have the 3rd brush adjustment at a minimum - turn up the 3rd brush for a higher charging rate and recheck. You should get 20 amps or close to it at normal road speeds.

Does the ammeter show "zero" with the battery connected but the key and all accessories off?

The battery is charging if the ammeter hasn't been damaged and shows positive at engine speeds higher than an idle. The voltage at the battery should also rise from about 6.6 to about 7.2 or thereabouts. If you doubt the voltmeter readings put the car in a darkened garage, engine idling and headlights on. Then increase the engine speed to a fast idle and the lights should get noticeably brighter.

When is the last time you pulled the band cover and looked at the brushes and commutator? Commutator should be bright copper. All 3 brushes should have some reasonable length remaining and under spring tension against the commutator. Is the commutator oily from excessive oiling of the rear bearing?

Does the battery hold a charge? Charge it with your charger to an electrolyte specific gravity of about 1.275 and let it sit disconnected overnight, and check again 24 hours later. If it's lost the charge you probably have a bad battery, perhaps an internal short. A quick and sometimes meaningful test - to all 3 cells bubble hydrogen gas when on your battery charger?

My

With the engine running at a fast idle and the ammeter showing a 10A charge you should have around 6.8 to 7.2 V at the battery terminals.

The 0.2V increase in voltage you measured at the battery, when charging is too low.

How old is the battery and what voltage do you have at the terminals when it is fully charged, engine not running? For a 6V in good condition and fully charged you should have around 6.3 V.

Measure the specific gravity of each cell with a battery hydrometer. If low put the battery on a charger and see if the value increases. You can also measure the voltage across the battery with it disconnected, to judge the condition and charge level.

I'd suspect a problem with one of the cells in your current battery.

Spec's on your generator:
Main Brush Tension- 20 oz.
Third Brush Tension - 12 oz.
Max. Cold Output - 25A, 8.0V @ 1500 rpm

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I have a sealed optima battery so I can't read the electrolyte.

The battery reads about 6.2V at idle and 6.4V when you rev it.

The ammeter is at zero when car us off.

Why would the voltage rise only .2 V?

Fully charged Optima is around 6.4V, so it sounds like the battery is OK.

With your current low / no charge voltage I'd look at closely at all connections and cables, the regulator and generator.

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Also did some testing with the lights on. Ammeter reads about 2A charging when fully rev.

Since it shows a charge (though small) you know the generator is working, it's a matter of quantity.

What was the condition of the commutator & brushes?

What happened when you adjusted the 3rd brush for more output?

And what is the generator model number?

You could remove and lift up the regulator and unfasten the field wire, then reattach the regulator. Then with the engine running use a jumper wire to just ground the field wire momentarily. If the generator output jumps to 20 or so amps, the problem is the VR755. If the output does not increase, the problem is the generator.

Another thought, just temporarily replace the battery with one known to be good, just to eliminate that possibility.

I actually found my spare VR755. It didn't make a difference. I popped the cover and it look pretty dirty inside. Commutator was not clean and shiny. It was not clean inside which may be part of the problem.

I have not adjusted the third brush.

I think my next step may to be remove the generator and get it serviced.

Gen is a 1002 with a red label.

Certainly removing the generator and having it serviced by someone who is competent (like Jason at AER, or Ace-Wichita) is a good idea and when done you know you'll be set for tens and tens of thousands of miles. But my curiosity would get to me before that, why not just clean the commutator and see what happens? First, try just a bit of solvent on a cloth against it while it's turning to remove an oily residue, followed by a light polish with some fine crocus cloth or similar. Nothing to be lost by trying this other than 15 minutes of your time.

I don't know how familiar you are with the generator installation, so be CERTAIN that the bronze adapter plate stays in place in the timing chain housing when removing the generator. Should it come out with the generator the sprocket and timing chain will drop to the bottom of the pan and then it's off with the radiator, etc.

So I assume you clean the commutator while the engine is running, correct?

To make sure the brass adapter plate stays in place, is this a two man operation? One to pull the generator, and one to hold the brass plate against the crankcase?

Do you agree it appears that the generator needs to be serviced?