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I just replaced the water pump and hoses on our '48 Packard deluxe 8. I removed all the small components at the same time to detail the components and the engine, and replace some crispy wires (until the new harness). Anyhow, I know the gen needs to be polarized, but can't find which terminal to jump to accomplish that... I've got all the books for this car, but can't find it anyplace.
Thanks in advance for any help, Kelly

Not sure it's in the 48 manual but here is instructions from 51-4.

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Thanks a million Howard! You get the "what a guy!" award for today.
Kelly

I realize I'm showing my ignorance here, but what happens if the generator isn't polarized? I recently installed a rebuilt generator. Some weeks later I added a new voltage regulator. No polarization took place at either time, so I'm wondering if I'm asking for trouble.

Thanks much,

Mark

If it's charging OK, no problems.

The generator is disconnected from the battery when engine is not running. Because there is nothing powering the field coils, it relies on a tiny bit of residual magnetism in the iron. If that is present, once armature starts spinning it can start putting out a small voltage to bring in one of the regulator relays and connect the battery. Once battery is connected, field is at strength and regulator starts it's thing. Polarizing works like an electromagnet and magnetizes the iron and also ensures the N-S poles in the generator are correctly oriented so the output polarity is correct.

Polarizing is a good idea in case something accidentally was reversed and is recommended as a matter of thoroughness. If a new item (generator in particular) was installed, there may be no residual magnetism so will be needed. If the battery was reversed, the poles will be the wrong orientation and polarizing corrects things to the current configuration.

After polarizing a generator you want to make sure the cutout relay which is part of the regulator actually cuts out.

Back in my misspent youth I have poked around with clip leads and managed to engage the cutout to find a dead battery later.

There are three relays in a regulator and one operates as a cutout so the way I would polarize (misspent youth) was to manually engage the cutout relay armature, but once you do it stays latched in until you disconnect the battery.

Jim

Hi folks

Before everybody starts poking around their voltage regulator and manually closing contacts let's look at what is actually going on with this polarization stuff.

Firstly, if the cutout is closed with the motor off the ammeter needle will be buried or the the Gen light will be on so you don't have to take the cover off the regulator.
In either case not disconnecting the battery will result in a fire. Sticking regulator cutouts on old regualtors are one of the reasons disconnect switches became popular

What polarize means is to momentarily feed battery voltage to the generator armature. That is A - armature and B - battery. The field terminal (F) is a pulse modulated ground and should not be used.

This procedure is highlighted in the Delco Manual, but they don't say what it actually does other than to say that not polarizing the generator after the battery is disconnected can result in "severe damage". This is of course contrary to mass experience because, were it true, every car with a disconnect switch would burn up.

Usually what happens is that the generator doesn't charge until it is properly polarized.

So just what is Polarize? The regulator has dual windings around a soft iron core. When battery voltage is manually applied to the armature the north and south poles of these soft iron cores are established which allows generator voltage to close the cutout.

Hope this helps

Here's a real basic question: what should the output on the properly polarized 6V system be?

Not sure which output you're interested in.

Voltage, about 7.4 to perhaps 8.0 volts (cold). You can find specific specifications in old Motors Manuals as well as other places.

Amperage, gradually increasing from the early 20s when cars had few electrical accessories. The early 30s were in the range of 25 amps, 40s in the range of 30 amps, 50s in the range of 35 amps.

Name a specific year and model and generator # or make if original to the car and I or someone else will get the specs if you can't look it up.

Depends on the model and equipment but if you're speaking of a 1940 senior with Autolite, page 32 of 1940 service manual lists regulator settings with nominal values of approx 7.4v (7.36 to 7.66) at 35 amps (34 to 36). Those seem to be a pretty standard value Packard used on a typical 6v system of the era.