Forgot to polarize generator - what next

['51 Special]

I recently installed a generator of a 1950 Buick on my '51. Other than installing a narrow-belt pully, I made no changes to the "new" generator. However, I did disassemble it to clean it up as it had been sitting in a hoodless engine compartment for many years. It had a very recently (in use, not in time) cleaned-up commutator and new brushes. After cleaning it up, I painted it, replaced the wide - with the narrow-belt pully, and "motorized" it to verify general function. All went well. I installed the generator on my battery-less and not running car.
About two weeks go by, I get everything assembled, and start up the newly overhauled engine. (Except for turning the key, all starting of the starting procedures took place under the hood.) When I looked at the instruments to chek oil pressure and water temp, I saw that the charge indicator was registering deep discharge. This is when I remembered that I had never polarized the generator. I shut the car off, polarized the generator, still deep discharge. I have not yet opened up the regulator, but it was previously working fine with the old generator.
My questions: Is this problem likely or typically caused by failure to polarize the generator, or is it more likely to be some malfunction I have not tested for? I it is likely due to failure to polarize, can it be fixed using the cleaning and adjustmnts described in the Buick Shop Manual, or is the regulator toast? Thanks for any suggestion on this.
'51

[raycow]

Does this deep discharge occur with the engine running, not running, or both?

Ray

[raycow]

Does one generator have a straight case (constant diameter for its full length) with "windows" (or a band covering them) at the commutator end, and the other generator have a stepped case (smaller at the commutator end) with no windows?

If yes, the positions of the "A" and "F" terminal studs are reversed, so check that your wire connections are correct. If there is any doubt, the thinner of the two wires must connect to the "F" terminal, no matter where the terminals are located on the case.

Ray

['51 Special]

Ray-
The charge indicator shows slight discharge with the ignition switch on and the engine not running. If I turn the lights on, with the engine not running, the charge indicator shows an increaed discharge, but not nearly as great as with the engine (and generator) running.
The generator I took off is a Delco-Remy 35 Amp. Model No. 1102667, Serial No. 1G14 (correct for 1948-48 Chevrolet) with 5/16^th inch mounting hardware. The replacement generator is a Delco-Remy 42 Amp. Model No. 1102709, Serial No. 0B23 (correct for 1950 Buick), with correct 3/8^th inch mounting hardware. The cases on these generators have identical dimensions and external appearance, except the end-plates on the 35 Amp. Model No. 1102667 have the smaller holes for mounting on the vehicle. The information on the correct applications for these generators comes from a 16th Edition Motor's Auto Repair Manual with a 1953 copyright.

[raycow]

Please describe the procedure you followed for polarizing the generator. I actually found an error concerning this in the 1952 manual, which is the one I use, and I don't know if the same error also appeared in other editions.

Ray

['51 Special]

Ray-
I use a 1951 manual but may have seen the error you refer to. In manual part 10-26(b)(page 317), concerning "Testing Generator Output and Generator Circuit Wiring, paragraph 6 provides:
"Disconnect ammeter and reconnect loose wire to 'BAT' terminal of regulator. Leave jumper wire connected between 'F' terminal and regulator base. Momentarily bridge between 'F' and "GEN' terminals of regulator to polarize the generator."
This conflicts with manual part 10-29(a) (page 320), where the fifth paragraph explains the importance of polarizing the generator "after all wires are connected but before engine is started." (Emphasis in original.) That paragraph ends with this sentence: "The generator may be readily polarized by momentarily bridging between the "BAT" and "GEN" terminals of regulator to cause a surge of current through the generator."
I used the method described on page 320 ("momentarily bridging between the "BAT" and "GEN" terminals of regulator"). I thought it was consistent with instructions in my 16th Edition Motor's Auto Repair Manual paragraphs on polarizing generator: "If the generator is externally grounded, momentarily touch a jumper lead to the armature and battery terminals of the regulator." I assumed the generator is "externally grounded" because it has a ground wire running to the regulator. Wrong guess?
'51

[raycow]

You're good. That's the exact error I was talking about.

To be honest, I am not really sure what "externally grounded" means when it is used in that context. My best guess is that the ground wire stud is insulated from the case, so that the generator is NOT grounded through its mounting. However, the ground stud was not insulated on my generator when I had one (I run an alternator now) and I polarized mine the same way you did - and it worked fine.

So the bad news is that this probably isn't the cause of your trouble, and I am out of ideas at the moment. I don't think your cutout points are stuck closed (this is a common type of regulator failure) because the ammeter isn't showing a current draw when the engine isn't running (ignition switch off).

If you are agreeable, I would ask that you run a few more tests. First, disconnect the armature lead and see if this has any effect on the ammeter when the engine is running. Second, re-connect the armature and disconnect the field and check the ammeter again. Lastly, ground the field as described in the manual. This takes the regulator out of the circuit, which means there is nothing to limit the output current, so keep the engine revs down - my manual says 1300 max.

I have one other question, but I'm not sure yet if it is relevant. Is the gas pedal start feature still working on your car? The reason I ask is that the ground side of the starter relay coil is connected to the GEN terminal of the regulator.

Good luck, and please post back with whatever you find out.

Ray

[65specialconvert]

You did polarize it correctly,but it needs to be running when you do it.
The generator is grounded without the ground wire,some regulators have an isolated base to run positive or negative ground.So making sure the regulator is grounded properly is important.

['51 Special]

Ray-
I haven't yet run your additional tests. (It is raining here, and I have no garage for the Buick, so the cover stays on when the weather goes sour.) I will update after things clear up. FYI, the starter switch still operates with the accelerator pedal. I like it that way because I can start the car from under the hood without a starter jumper.

65specialconvert-
Your suggestion that I polarize the generator when it is running runs contrary to the Buick Manual and the 16th Edition Motor's Auto Repair Manual (whether or not the generator is externally grounded). But I see also that you are in the business of working on generators, and I have not had any luck following the manual after I started the car without polarizing the generator.

I just pulled out my 19th Edition Motor's Auto Repair Manual (1956), and here is how it says to polarize the generator: "Before connecting any wires to the regulator connect one end of a jumper wire to the armature 'A' terminal on the generator. Then momentarily touch the other end of the jumper wire to any hot wire or terminal." (I assume that by"Before connecting any wires to the regulator ..." they actually mean "Before connecting any generator wires to the regulator ...")
And my 1942 Motor's Auto Repair Manual includes a section describing several types of generators. Their diagram of a "two-brush shunt generator" is essentially the same as their diagram of a generator "with field circuit grounded outside generator." The Buick Manual says that the installed generator is a "two-brush, two-pole shunt wound unit." I believe this means we are dealing with an "externally grounded" generator.

My plan is to try, in order:
(1) The guidance of the 1956 Motor's Auto Repair Manual (disconnect the armature and field wires from the generator, connect a jumper to the armature terminal, tap the other end of the jumper to a hot terminal, reconnect the generator) start the car, and see what happens. If still showing strong discharge, go to (2).
(2) The guidance of 65specialconvert (with the engine running, momentarily bridge between the "BAT" and "GEN" terminals of regulator, and see what happens. If still showing strong discharge, go to (3).
(3) Run the tests as Ray suggests.

['51 Special]

Ray and 65specialconvert-

Well, this may be embarrassing. I was busy checking the functioning of electrical accessories, in part because I had taken both the instrument cluster and the steering column out. (he instrument cluster came out because the temp gauge needed repair. The steering column came out and, except for the steering wheel, and the turn signal switch gear and wiring, was replaced with parts appropriate for a manual transmission. (I swaped the leaky Dynaflow for a manual transmission. Another long story.) I was concerned that I may have made mistakes when hooking up the wiring.

The turn signals are not working, a problem discovered but not solved. However, when I was checking out the heater and defroster blowers, I pulled out the light switch. It worked, but then I glanced at the charge indicator. The engine was not running, but the indicator showed charge when it should have showed discharge. I rubbed my eyes, and tried again. Sure enough, with the engine off and the ignition on, the indicator said the system was charging. If the load was light, it showed slight charge. If the load was heavy, it showed strong charge.

I now suspect that the generator has been charging all along, and I have hooked up charge indicator backwards. Does that make sense to you?

'51 Special