VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 Charging problems

Hi Everyone,

Working on the '50 and not having much luck so far. I've checked connections and got a new battery with a good charge in it. I used a jumper wire from the battery+ terminal to the A terminal on the generator, it turned like a motor (I did have the belt off). The I figured maybe I needed to polarize the generator as the car has been sitting 30+ years. It didn't change a thing, still not charging. I used my digital voltmeter and did show a slight charge coming off the generator, less than a volt though. I had noticed when I had the generator spinning it did make some noise. I figured that I needed to have it taken apart and cleaned up at least. I took it to the local starter shop and they put it on the test bench, I put out 30+ amps and 6.5 volts. So I guess that the generator is ok, but I am having it taken apart and cleaned up and probably a new set of brushes anyway. I've taken the cover off the regulator and checked to make sure that the points were not stuck or corroded. Everything nice and shiny clean inside regulator. I'm wondering what I need to do once I get the generator back and installed? Do I need to polarize it again? The way I understand it to polarize I need to jumper the G terminal with the B terminal on the regulator. So, looking for advise what to do next.

Thanks

Every time the generator is removed and reinstalled it must be polarized. You can polarize the generator as you described in your posting. Make sure the ignition is off and all wires are hooked up. If your generator still doesn't charge then you will need to look at the voltage regulator. Check your shop manual for details on how to test the regulator to see if it is defective.

:) :grin:

Thanks Junkyard Dog, I've been reading my shop manual and I can't find anything about how to full field the regulator. It is probably in section 12 but I'm not getting it.

Thanks

Touch the field wire to ground and that will full field the generator. Increase engine speed and if there is no charge the generator is defective. If there is a charge then your regulator has a problem.

:) :grin:

So I take the field wire off the regulator and ground it? Or the field wire on the generator?

Thanks

Take the field wire off the regulator.

:) :grin:

Hello Junkyard Dog,

You mentioned that you need to "polarize" the generator each time it is removed and reinstalled. Does that also mean you need to "polarize" each time the battery is disconnected and re-connected ?
My car battery is always disconnected when the car sits a couple of weeks, and I'm sure other owners may disconnect their batteries if their cars sit also.

I've never "polarized" the generator in 8 years since I've owned it and another friend has never done this in 20 years, except the time he had his generator re-built, then re-installed.Then again, perhaps that is why i've never got more than 2 years out of a battery.

No, you don't have to polarize the generator each time the battery is disconnected.

:) :grin:

Ok thanks junkyard dog, it seems like a lot of differing information out there.

The article below is what confused me: http://www.starautoelectric.com/Technical.htm

It states that whenever the battery is disconnected the generator needs to be polarized. Other articles I found online state that you only need to poarize if the regulator or generator is repaired, tested or replaced.It didn't make sense to me to do this each time you disconnect the battery.
Here is an article I found online for testing a generator, worth printing out as guide for anyone interested. http://www.nls.net/mp/volks/htm/gen.htm

Ya, they are saying that the generator "should" be polarized each time the battery is disconnected, but in reality, that is really not necessary.

:) :grin:

Hey I got a bright idea JYD. Why don't you explain exactly what the principle is behind polarizing the generator, then all of those guys that are new to electrical work can fully understand the how and why of the task.
Denny Graham
Sandwich, IL

Total agreement with the above. I have a "Green cable end" I disconnect the battery every time the car is parked in the garage. No need to repolarize every time.

I got the generator put back on. Ended up having new brushes put in and also replaced the front bearing. I put it on the car, I went ahead and polorized it even though the starter shop said I didn't need to because they did it when they put it on the test bench. All hooked and and still not charging. I took the field wire off the regulator and grounded it. When full fielded it charged like it was supposed to. I check the field wire for continuity and it was ok. I guess I have a regulator issue.
Whats the next step in checking out the regulator?

Thanks

That is incorrect. As mentioned earlier, the generator must be polarized each time it is removed and reinstalled on the car. Even though your generator was polarized on the starter shop's test bench, it still must be polarized again when you put it back on the car. So, by polarizing your generator when you installed it back on your car you did the right thing.

Sounds like you will need to invest in a new voltage regulator.

:) :grin:

I was reading in my service manual and it talks about setting the voltage and also adjusting the regulator. Can these operations be done without the tester that they refer to using in the manual? Or can I put my regulator on the bench and test it?

Thanks

For correct results I would use the proper test equipment. Even with the correct equipment, a voltage regulator is not an easy owner type repair.

In 1950 the station I worked at had a tune up shop (called the Battery shop still rebuilding them) any way there was one tune up guy that did all the VR work. He was very good at a touchy job. Others could do it but mostly all that kind of work was turned over to him.

what is the "proper" equipment to use?

I don't know what year you are working on, but for example the 1941 shop manual shows a Multimeter in use on page 26-4.

I have a multimeter unit from Craftsman that includes all the necessary test leads and a resistor to use during the load tests.

If you have a Motors Manual, of the early vintage, it also shows the step by step and shows the equipment needed.

I have been at this job for many years and I think I have mastered most cases, except, the early Pontiacs and Buicks, which used a two stage VR. The quickest way to handle one of those was to replace it with a normal single step VR. I took one car to the dealer to have the VR set and he said he did not have a qualified mechanic who could set it correctly.

Voltage regulators are not only tricky but hard to adjust for the post part. You would be a lot better off installing a new voltage regulator instead of trying to fix the old one.

:) :grin:

The adjustments set the charging rate only. If its not working either the contacts are dirty or there is a problem and replacement is necessary.

Replacement Voltage Regulators are not cheap, so be sure and check it carefully before ordering a new one. New ones are available from the Filling Station, Chevs of the 40s and other suppliers as well as local parts houses. I got one from NAPA about a year ago.

Hi Everyone,

The charging issues are solved. My '50 is charging just like it should. I ended up having the brushes in the generator replaced and also the front bearing. I did also purchase a new US built regulator. I cleaned all the connections also. It is charging at 7.4 volts. The battery is fully charged and the amps drop down at idle, when I put the headlights on the amps go up like they should to maintain the load. I ended up confirming the the regulator that was on the car when I got it was bad. The Delco regulator that I pulled off my '49 pick-up in the shed is good, just needed the points cleaned and then adjusted the cut-out relay and it worked good on the test bench. I'll put that back ont he pick-up so its complete when I'm ready to get it back on the road again. I ended up paying just over 70.00 for the new regulator.

Thanks for all the help
Don

Hello Guys,

Just following up from this post of a few weeks ago. I think I now have a charging problem. A few months ago I did a post on a battery problem I had. I managed to fully charge the battery with a charger. Also drove the car a few times in the last 2 months during the day with no starting problems, and it seemed ok. Last night I drove the car at night for the first time and with the headlights on the amp gauge dropped to the extreme left whilst idling in traffic, and the turn signals froze or didn't work properly. The gauge did move to the right again at acceleration. After turning the engine off in a service station I was unable to start car again, as it appears the lights drained the charge from the battery. Coping abuse from people at the station for holding up the fuel queue I managed to push the car to a corner.

As I had no jump leads I called the mobile service mechanic and he put a volmeter on the battery. It read 6.3 volts and said the battery was ok ? I have charged this battery on and off over the last 2 years. I then got a fast jump start and at medium throttle the generator is putting out about 6.3 volts approximately according to the voltmeter, and slightly lower with the lights on. He seemed to think this is too low, so do I as I thought the charge rate should be at least 7 volts or slightly more ?
I also haven't looked at the voltage regulator although it had been replaced and looks newish like only 9-10 years old (limited driving over the last 8). I do have a rebuilt 53-54 generator in a box. Do you think I should just replace the generator on the car or get a new battery or both ? Don't know how old the generator on the car is, it may have partially worn brushes etc.
I am also hoping the regulator insides hasn't arced or anything, as I didn't really want to buy another one.
Any advice would be appreciated.

The engne would have to run at a fast idle for about 20 minutes to get up to the 7 volts. If it does the charging system is working. Are you usig halogen bulbs in any of the lights?
A test of the generator would be to short out the field terminal while the engine is running at about 40 MPH....this should cause the dash ammeter to go way to full charge.
The battery really should be load tested. I assume that the cables are in good condition and are of the larger diameter that is required for a 6 V system.

Thanks Gene. My cables are the correct thick ones with the braided earth cable. All the other wires from the regulator to the generator are tight and don't appear damaged or anything. The fan belt is also tight as it should be. My headlights are the standard T3 6 volt sealed beams, and all the bulbs are standard. The car is idling quite slowly so I can up it up slightly perhaps.
When you say the battery should be load tested, do you mean turning on the lights, radio etc then testing the voltage between the positive and negative terminals when the engine is not running ? Also do you know what the voltage should read approximately ? I was thinking of replacing my generator since I already have a re-built one sitting in a box and then driving the car for about 45 minutes to see if this will fully charge the battery, then testing the charge capacity with a multimeter with the engine running.

to test the bsttery with a load you use a "battery load tester"...It has some coils that place a heavy draw on the battery and the voltage is tested with the draw and time is taken into consideration.
If you have the required 100 AMP hour battery it will take 4 hours to charge it at a 25 amp charge. Its pretty difficult to get a 6 V battery fully charged in 45 minutes.
The correct proceedure would be to fully charge the battery and then load test it. You are welcome to borrow my load tester :)Here in the US you can buy a 6 and 12 V tester for about $40.00.

Thanks for this info on the battery load tester Gene. I installed my rebuilt generator last night. I noticed that the A and the F on the rebuilt unit were back to front. It had no tag on it so I don't know what serial number it was. The rebuilt unit did have the correct ID plate number for 53-54 as per the manual. When connecting I just made sure the connections corresponded to the regulator A & F. Also,looking at the end of the generator I pulled off, the brushes look a little worn but not too bad. I didn't pull it apart or anything. Anyway, I have the battery on high charge overnight to get it fully charged. Once it's done, I will connect the battery leads, polarise the generator, and drive about an hour. I think I'll wait to check out your load tester next time I visit the States:-) The problem I've found here is that there are not many people left that know how to test anything properly, the way things would have been done in the old days. I guess we have become a throw away society where people just replace, and it's sad that skills (particularly in auto repair) are slowly disappearing. That's what I've found here anyway.

Being expected to perform certain time-honored rituals because this is the way you were always instructed to do it just isn’t enough for me. Since I’m the curious type I want to know the why behind my actions, you know, the principals. So, in answer to my question, “exactly what happens when you polarize the generator,” did some further research and found this article. Now you old timers probably won’t be interested in this or want to waste your time reading it, cuz ya all ready know all this, but there might just be a few of you that don’t know it all but would like understand this exercise in depth.
http://web.utk.edu/~tprather/FoothillsTractorClub/TechTips/PolarizeGenerator.html
Denny Graham
Sandwich, IL

I kinda figured it was something like dat! Wuzzn't real sure, jest knew it had to be done, because my Pappy told me to do it.
Thanks!

Same here Mack, pop was an old school mechanic trained in the 20's and he taught me young, all so worked auto parts in my teens and 20’s, but I'm now '66 pushing '67 and I been doing the same thing all my life and really never asked about the physics behind it. Apparently the pole pieces can retain some residual magnetism so ya just need to set it right for the polarity of your system. That's a surprise to me because I worked around electromagnets for almost 30 years at the USA's Jewel, Fermi National Particle Accelerator and that just didn't happen to the pole pieces in our magnets. In fact that was a characteristic that we tested the incoming pole piece material for.
Denny Graham
Sandwich, IL

Here is a neat little something I learned today, Instead of going bonkers trying to isolate generator/regulator malfunctions for 4 months, look underneath your dash at the 2 wires going to the ammeter. Funny thing, if they arent tight... Gosh, I feel about as dumb as a mule with a spinning wheel.

The main wire come off the battery and attaches to the ammeter. all power then passes through the ammeter and goes on from there. The ammeter connections are very important. If the ammeter were to burn out the power would be cut-off at that point.

It seems that since I corrected this. Everything else electrical rectified itself. In theory, poor connections create resistance, thus, not a proper flow of electrons giving the entire electrical system limit from full power. I thought it was wierd when I would go over a bump, or railroad tracks, the ammeter would jump to charge. But didn't last long. I figured it was making the regulator points bounce closed. Gene,in your years at the dealership have you ever encountered a poor, but not entirely cut off connection where it was functioning but not to full capacity? I can almost imagine all of the crazy things would have seen in the fix it yourself era full of farmers with a tin snip and a pliers.

Years ago, about 40 of them to be honest, I had a 52 F*** flathead 8 that would run fine as long as it was on a halfway decent road. Hit a few bumps and it would start jerking like it was running out of gas. One dark night I lifted the hood and had some friends rock the front fenders. I could see sparks coming from one of the coil wires when they did that. Leave the car alone and it ran great. Replaced the wire and all was as good as it could be until I fully corrected the problem by getting another Chevy. :)

Guys, Thanks for all this information. Just for the record I have checked all the connections and they are tight. There is however some original cracked wires under the dash mainly having to do with the turn signal connections into the original plastic connector, and some cracked wires where it joins onto the front terminal blocks. I have replaced the headlight wires and the connections to the coil, and generator to regulator. So I think I will replace the bad wires still remaining.
A few days ago I took my battery to the battery shop and they put a battery load tester on it (as Gene suggested). He confirmed that although the battery had plenty of charge (about 6.3 Volts), it failed the load test. He said one or more of the cells in my 2 year & 2 month old battery has failed or sulphized ?, hence the reason it didn't hold its charge. It also made the indicators operate very slow or freeze, & gear shift indicator lamp did not come on when headlights were on and car was running. Bought a "deep cycle" 6 volt battery that fit the tray size. It is 550 CCA. The previous one was 650 CCA but that's all he had available. Haven't had one of these "deep cycle" batteries before but they apparently are more resilient to several discharge/recharge cycles as oposed to the standard auto battery, and have less current drain. Took the car out yesterday and it starts fine. At idle the amp gauge needle is slightly below centre but moves to the right at idle. I also opened the regulator lid and checked the points, nothing dirty, arced or stuck and my generator is now replaced with the rebuilt unit, and is charging fine. All lights appear to work as they should. Hopefully frustration solved.

I would be curious to know if anyone has adjusted one of the regulators that doesn't have the adjustment screws. I think they are just the worst thing to work on!

Just going from memory-
On the later replacement regulators that did not have adjusting screws they bent the little tangs that the spinngs were hooked to.

I'd forgotton about adjusting them. It was a VERY long time ago but yes, I did adjust them. I don't think I would try it today unless I had another regulator laying around so it would be safe for me to screw up.

I've got a couple of them like that on the bench right now and a Delco with the screws. I know just what you mean, the adjustment needs to be very fine and bending the tabs on the after market regulators is next to impossible to get right. The Delco is very sensitive and much easier to resolve. As long as the contacts are clean and not burned and all the windings show continuity and aren't shorted the only thing left to getting them to operate reliably is the adjustment that must be done in fine increments.
I would say that if your having problems with an after market regulator the best fix is to replace it.
Denny Graham
Sandwich, IL

I was wandering the rows at a swap meet yesterday and was found a guy selling new replacement parts from an old inventory he purchased. He had multiple "rebuilt regulators". I'd never heard of a rebuilt regulator but had a number of them in the box. I don't remember the brand name. I was going to buy one just to check it out but figured different when the guy wouldn't take less than 50.00 for a GM 6 volt.
On adjusting regulators, When I was working on my '50 this summer I had a couple regulators along with me at the starter shop. We had the generator all gone threw and working, then we wired up a delco regulator, no go. We check the points, all good. Then we adjusted it per the service manual and it started working but found that it was wanting to overcharge. It was also interesting that when we would stop spinning the generator sometimes the regulator would pick and and work and other times it wouldn't go. When it wouldn't go we would just touch the screwdriver to the cut-out relay and it would go. All the connections looked good. Then I had a aftermarket regulator that we hooked up. As Denny has said its tough at best to bend tabs for adjustments. We could get that regulator to kind of work. It always ended up that we felt it was acting almost like it was full fielding the regulator and I was nervous that it was going to overcharge my battery. I ended up getting a new regulator and once I got it adjusted the car charges perfect. I'm still hoping Denny can come up with a plan to repair these Delco regulators.

Thanks
Don

Ya, rebuilt regulators were common years ago. Bought several over the years for my '51 Chevy.

:) :grin:

The Echlin that ya sent me Don is one of those that needs the (bend a tab adjustment) I’ve messed with it for a while and just can’t get any consistency with it either. I have a late model Delco (probably made off shore) that is also adjusted by bending the tabs. The Delco that I am running on my ’50, 3600 is the old style and is fully adjustable with a screwdriver. I can hook the meter up to this one and make adjustments through out the range in .01v increments and it holds that setting. Not so with the other two.
I suppose I should have mentioned a couple of other problems that you can encounter with a used regulator.
Unless you have the resistance specs and a meter that will measure into fractions of and ohm it is difficult to diagnose a layer-to-layer short in the coils. The coil can be shorted internally and still check out ok. The regulator will appear to operate normally except it will stick once in awhile. Also the ground path is through the iron cores which double as rivets to mount the coils. Corrosion at this joint can ad resistance to the path, which upsets the adjustments in a regulator that has been in service for a while. There isn’t much you can do about either of these problems, it’s just not cost affective and you would have to manufacture new iron cores and wind new coils.
Denny Graham
Sandwich, IL

This is on my cub farmall with positive ground. I can't get my generator to charge after installing and sanding new brushes and cleaning armature. Took it to one place and he said it didn't charge. A friend hooked it up to a set of jumper cables and it turned like a motor. Took it to another and he said it charged the full amount. Reinstalled and nothing showed on the amp gauge. Touched the field wire to ground and it showed discharge full amount and the lights went dimmer. By the time I took the wire off ground the generator stared to smoke. Any ideas? Did I do something wrong being it's positive ground? If it turns with the jumper cables does that mean it's working? Will get the nieghbor tomorrow night to check it with his amperage gauge. I did polorize it "Bat" to "Gen" like the cub farmall book said.

No. I have had generators that would motor fine but would not charge.

Thanks Dawg, being it showed discharging and lights got dim must mean it's not working. Will get it checked out again to see if it can be fixed.

It can be fixed...ya just gotta find the problem.

OK. Just got back from a shop where I had my generator retested. It charges great when on a negative ground only. I have a positive ground on the cub farmall. Can this be reversed by polorizing or is it possible to change the wiring in the generator to switch it over to a positive ground? Couldn't find anything in our searches or on the internet. Thanks.

Jerry, did your daddy never tell you about that special lever on a tractor? That one that he called "Lever B"?
Well just lever B a positive ground Farmall Cub and the wheels won't get flopped over cross ways and run off into a frozen lake! BRRRRRR!

We have talked about polarizing generators a zillion times here on Chevy Chatter II. Were you out playing golf all those times and missed it?

Anyway, a generator doesn't care if it is positive or negative ground as long as you polarize it for whenever ground system you are using. After the generator is installed, polarize it for your positive ground system, and each time you remove and reinstall the generator is should be polarized.

I did read all 5 pages of this post before I posted yesterday and also polorized from "batt" to "gen" like tractor manual said. Touched the field wire to ground and it discharged. Going out right now to put it on and try again. Wish meluck.

Still no luck. Took it to the old timer like everyone said I should and told him the problem. He said I had to polorize it and I told him I did but still discharges when I touch the field wire to the ground. He asked if I ever had it apart and I said no and that I pulled it out of the woods at my Uncles place 19 yrs ago and got the engine running 2 yrs ago but the generator never worked and all I did to it was put in new brushes and clean armature. He smiled and said lets look in side. Yep, just as I thought, sombody reversed the wires. Took it apart, cleaned it up, reversed the wires, tested it and it worked. Now the good part. How much do I owe you. Oh, how about $10. I said here's another $5 for coffee. Do I have to polorize it again when I get home. No, just put it on the front seat with you for a soft ride. If you let it bounce around in the back of the pick up, then you might have to. Just put it back on and works great. Jaegermeister time.

Great news Jerry... Keep chasing those gemlins down... it'll only be another couple of years or so until you have your restoration done.... Ha!!

And you thought that you were done, once you were done. !?!?!?

Ha ha.... Enjoy the