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I have a 52 200 ,resto is almost done, and I can use her for a commuter BUT
I seem to go through a lot of generators! ,recantly have been plagued with a persistant battery light being on ,sometimes after the car is shut off .
I posted this one and got the advice to check the ignition switch .I replaced it, charged up the year old 6 v battery while I was working on it .Seemed to work for a bit .Not so long ago I had replaced the voltage regulator and while trying to figure out the battery light mystery I took off the regulator cover and checked its points, which looked ok no burning or sticking noted ,I polarised it as I had had the battery unhooked.
I had replaced the coil condencer and ignition points ,plug wires ,even the harness as part of the resto .

recantly the battery light came while driving on the highway at speed but not at street speed (,about a 120 mi trip over two days @60 mph including about 1/2 of the time with the lights on) , now the battery is dead .I guess the car was probably running off the battery not the generator and now ,run down,she wont start .Seems like the generator isnt charging at the higher rpm .this is my third generator .I'm guessing this one doesnt work when at higher rpm's ?Seems like a generator issue perhaps the rotor.
,Ive gotten rebuilt generators from both max merrit and kantor.perhaps they rebuild the brushes and paint them but dont check the rotors to check for shorts which might show up at elevated rpm 's .
In plumbing this mystery on the packardinfo site I saw an interesting post about high internal resistance from a weak battery causing charging problems ,I'M concidering a shotgun approach and switching the generator again as well as the voltage regulator but am worried about negative effect on my marriage .
I saw on the sites parts cross reference that the voltage regulator for a 53 was available through napa ,how about a 52?
the belt is a modern one and not the big old size,too tight destroying the generator?
CLUELESS!

Did this problem start recently???? was everything working ok up until u made somekind of change????

THe service man ual should outline a test procedure for the generator. Perform the test procedure as outlined in the service manual. Let us know the results.

It is possible that the battery is faulty. somekind of internal short that is intermittent with road vibration.

Does the battery go dead directly after driving the car or does the car have to set a day or two before it goes dead???

Generator/regulator sets should give many tens of thousands of miles without need for service, and I'd be pretty confident those who sell rebuilt units have checked the field windings and armatures. So I'd think your problems lies elsewhere. When a generator fails, what is the model of failure? That would seem to offer the paramount clue to the problem.

The only idea I can think of as a diagnostic is to bypass all the existing electric wires in the charging circuit with new temporary wires and reevaluate.

Failures of alternators on late model vehicles are often due to a problem with the battery; the excessive draw from an internal short can wreak all sorts of havoc. Battery problems can actually begin in hot weather, but don't fully manifest themselves until the heavier demands of winter operation.

Take your battery out to someone who can give it a full charge and proper load test.

Once the battery has been eliminated as a problem, check the condition of the cables - including the wire gauge. A 6V system requires heavier gauge than 12V.

Even if you swap out regulators, you'll still need to perform checks and adjustments, per the shop manual, which also provide a check of the generator. So, why not do it now, with the old regulator?

You may also find additional insights in the Serviceman's Training Book - Scientific Diagnosis.

EDIT (11/1/11): A latent error was discoverd in the Scientific Diagnosis Training Book, regarding the use of a jumper lead on the regulator as part of a generator output test. Details of the corrected text were provided in STB 51T-34 and reiterated in SC Vol. 26, No. 1.

It's the holy trinity in charging: Generator-Battery-Regulator. If any one of the components is marginal, it puts strain on the other two components which in turn can lead to their failure. Then you replace the part that failed, not realizing the it was one of the other components that lead to it. So in a few weeks/months the replaced part fails again.

Inspect all the components. Also use a multimeter between the two battery cables without the battery hooked up, and with everything turned off to see if there is anything drawing against the battery.

You might want to make sure your battery terminals and battery cables are clean and tight; cables are of the proper size (0 or 00 gauge) and in good condition on both ends; and you battery is in good condition. Also check wiring on voltage regulator for bad connections or bad wiring. Check for ground strap from engine to body and body to frame. Good luck. Many times during a restoration electrical mounting/contact areas are painted causing a bad ground.

(o[]o)

Finding a 00 battery cable to run to the starter can be difficult. But you can go to Napa and buy the cable, and then some ready to solder copper connectors. They have solder and flux inside of them - just stick the copper wire in and heat the connector with a propane torch. Just remember to buy the lead connector on the other end in "ground/negative" size. The ground and hot connectors I looked at Napa were slightly different sizes, and the hot one wouldn't fit on the negative side. This made a huge difference on the cranking ability of my starter, and eased the load on the battery.

Did you polarize the Generators when you install them?

Also welding supply stores sell 0, 00, and 000 gauge cable as well, and may be able to put the terminals on for you.

Certainly O or OO gauge cables are important for good 6-volt performance and they should be replaced if yours aren't up to snuff. Clean connections expecially the ground on the battery cable is important as well. But cable size is extremely unlikely to be the cause of your problem. Your starter can draw upwards of 500 amps and hence the larger cable, the generator output is around 25 amps, just look at the size of wire from the armature to the BAT terminal, very much smaller - even an extremely undersize wire can carry that load as long as you don't have to start the engine again.

You did say you polarized the generator. Did you happen to put a voltmeter across the battery as a simple test of the charging circuit? With the engine idling, battery voltage should be about 6.6, give or take. Rev up the engine with a load on like headlights or heater, and it should rise to perhaps 7.4, give or take. Also of course the headlights should get noticeable brighter.

With a fully charged battery, driving 150 to 200 miles of daylight driving with no charging circuit is entirely possible - I've known many folks who have done that. Perhaps you've never had a functional charging circuit?