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Hey guys, I've been back and forth with this issue. I ran my battery down with a bad generator. I replaced the generator and finally the ammeter showed a charge however it was only going a little over the center point between d and c while accelerating. And wasn't showing much of a charge with the multimeter. I finally replaced the regulator and it shows a little more charge, my battery is still dying after a few cranks so that's getting replaced tomorrow, my real question is, does a proper working ammeter shake back and forth while accelerating, I figured it would be a steady rise and drop, but it shakes in place. My multimeter shows a decent charge, 6.25 volts car off and up to 7 volts with car on throttle open. But my car is still dying after small trips, I'm assuming the cold cranking amps are used up? While cranking, the battery drops below 2 volts. Sorry I'm all over the place just don't want this to be a constant issue.

The ammeter action depends a lot on the state of the battery and the speed of the engine. With a fully charged battery, after the starter is used and the car starts, at a steady over idle or cruising RPM typically you will see a fairly good charge rate for a few minutes until the battery is brought back up. Once that is done, as long as there is only a modest draw then the rate typically is just slightly to the charge side and is relatively steady. If there are a lot of high current accessories being used such as the headlights, heater or radio then the charge rate will be higher -- with all those on at the same time, it could be up to the maximum the generator will output. Generally the needle is still on the steady side -- possibly an occasional flicker if something is switched on.

The voltage dropping down so low when cranking is generally indicative of a battery or cable that is too small -- or a high resistance connection somewhere and even a cell failing in the battery. Dropping that low, I'm amazed the car will start at all. Generally if the voltage at the coil goes much below 4.5v the spark is so weak as to be almost non existent.

The important thing for those large engines is to have proper cables -- 0 or 00 gauge for 6volts -- and to get the largest CCA capacity battery you can fit in the holder. Some of us have even had to widen the holder slightly to fit todays available batteries. The long case batteries are not that plentiful but several have given the Exide 3EH with 850CCA available from Tractor Supply decent reviews. The Optima is recommended by others. Napa has a long case listing and some have used and recommend it. Personally, I think their 7205 at only 620CCA might be a bit on the marginal side. I don't know if they still carry any others that might be larger.

This is great info, I did get the standard replacement 6 volt battery from napa, and worked great for about a year until the gen went bad. I will check the battery cables tomorrow and make sure they're correct. I also realized after replacing the ignition coil and plugs, the plug wires melted from their boots (parts from napa) It's been causing serious issues trying to start when cold, now so to the point of having to use starting fluid everytime I start it, which also contributes to my battery going stale. Once it's on it seems to run very smooth, I already put the old ignition coil back on, hoping this will help the car start easier like it used to, I'm getting a new 6 volt battery tomorrow. That way everything will be correct again so I can start testing further and hopefully fix the problem.

This sounds like a repeat of what I had go wrong with my 1950 Series 23 Deluxe 8 Touring Sedan. When I got the Packard it had a new NAPA battery. The charging was poor so I had the generator rebuilt, got new (big) battery cables, and put on a new regulator. The charging was marginally low (negative charge at idle)and the car was hard to start. After a dead battery I fixed the short in the electrical system by replacing the entire wiring loom. I bought another new NAPA battery, which was dead when I put it in the car. After 3 NAPA batteries I finally got one that was not old and dead from sitting on their shelf for years. Then the battery would not charge so I gave up on NAPA and bought a new Vintage battery. The charging on that was low (negative at idle) so I had the regulator checked and adjusted by a specialist. The charging was still negative with the headlights and radio on unless running at 60 mph and the battery went dead after any long cranking. Finally the Vintage battery would not take a charge. I bought a new Interstate battery and had to widen the holder slightly to make it fit.

Since I have headlights, fog lights, a radio and plan to add an electric cooling fan I needed even more charging. I finally got a "Genernator" which is a one-wire alternator inside an original Packard generator housing. Now everything seems to work well, the car looks original, and the car starts easier. The output of the Genernator is up to 20 amps at idle! However it still cranks a lot after sitting for a week. The next step is to install a hidden electric fuel pump so I can start it with only a little bit of cranking. The fuel apparently evaporates out of the carburetor if the car sits for a week. This entire episode has cost me $3000 and I had to do much of the work. The bad wiring loom was the most expensive and difficult.

I hope my trial and error experience is of some help. Good luck on your Packard.

Fred, that must have been exasperating, though I don't understand it as those stock charging systems are usually completely competent and reliable when correct. In my experiences charging problems with conventional generators and regulators are few and far between and almost always easily solved. To show a slight discharge at idle (the current draw of the ignition system) is normal but it should have shown a charge at as little as a fast idle.

I've bought lot's of NAPA batteries including many of the one used in the 46-50 Packards, they were always fresh but I do routinely check the battery build date before turning over my cash and suggest others do as well.

In any case, glad you're back to functional.

Alright I did find a reasonably priced 6 volt 1 wire pos ground alternator on eBay. What's the best amperage for running a stereo with the 6 to 12 converter. Also been having some issues starting the car, it has to be started with starting fluid everytime unless car was running already. From a cold start it runs extremely sluggish for about a minute, having to give it gas to keep it on. I think it's the carb however it runs smooth when it's finally running.

Is it getting fuel pressure? Maybe you need to add an electric fuel pump, just turn it on before starting to assure fuel to the carb and then you should be able to leave it off. Or, does the accelerator pump in the carb work? Needs to have a decent seal to give a squirt of gas.

Couple of items. Make sure that the ground strap has a good clean ground on the body - no grease, dirt, paint etc and a good washer and bolt. The wire to the generator should be at least a 00 cable, available from Napa. I like to use the pre done cable ends - you just trim back the insulation, stick the wire in and hit it with a propane torch. If you can't find a braided flat cable for the ground, you can also use this technique for the ground wire.

It certainly made it much easier to start both my 39 and 51 models.

Sure would like to know the source of Fred Puhn's alternator disguised in the shell of a Packard generator.

Fred, could you pm me the information or post it in this discussion.

Thanking you in advance.

Sincerely,
Zougeride

I was crimping the ends onto the braided wire. Heating it with a propane torch makes it a more secure connection?
I will try that.
Thanks Dave!