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motive
11-20-2006, 11:27 AM
My Speedster has recently started showing a discharge for a short while after start-up, after which it starts charging normally. It can remain on the discharge side for 30 seconds to several minutes before the charging circuit kicks in. I recently replaced the voltage regulator and had the generator rebuilt and there was no delay in the charging circuit starting up. I also just replaced the battery, but this problem appeared before the new battery was installed. (I bought the new battery so I could keep the old one in the trunk as a spare in case I need 6-Volt jump as I have had hot re-start problems this past summer.) Could it be a cold/slow-to-switch voltage regulator? Once charging, it will show a small positive charge at highway speed with headlights etc. on, and a small positive charge at idle with lights off. So once working, it appears to be working normally. It's only the delay in starting to charge that concerns me. Any ideas out there?

Mike with Speedster

John Kirchhoff
11-20-2006, 01:50 PM
Can I assume the regulator change was for a new one? You might make sure the connections and ground are all making good contact to begine with. If it was with another old one, you may want to remove the cover and see if the contacts are cruddy. If so, gently clean them, sometimes dragging some fine grit sandpaper across them will suffice. Refrain from grabbing the offset head grinder or other more "aggressive" measures.

After running a bit, the slight charge shows it's working the way it should. If you continue to have problems let's hope there's smarter people out there than I because otherwise I have a habit of coming up with a solution at 2 AM when I should be sleeping.

motive
11-20-2006, 02:29 PM
Thanks John. The regulator was a new one anad everyting has worked as it should up for several months (with light use) until about a week ago. So something has changed. I've noticed that these 6-volt systems seem to be VERY sensitive to any kind of dirty connections, more so than 12-volt systems.

Mike with Speedster

55studeman
11-20-2006, 03:57 PM
Just a quick thought on this matter, having dealt with a few bad regulators and other 6volt irregularities myself.

We need a few more details for analysis:
1)After start up, during the discharge period, is the engine at regular 550 rpm idle or is it at fast idle?
2) Along the same lines, is this a cold start problem, i.e. a cold regulator or cold generator problem? To test, drive around and warm the car up good, stop the car for a few minutes and start it again -do you get the same problem?
3) With the headlights and all accessories turned OFF, what is the amount of discharge on the ammeter during the 30 seconds?


These questions I think should help a lot, please let us know what you find.



E. West
"The Speedster Kid"
Sunny Northern California
Where the roads don't freeze over and the heat doesn't kill you.
And an open road is yours to have -only during non-commute rush hours 9am-4pm and 7pm to 7am (Ha, ha, ha)

Dwain G.
11-20-2006, 05:53 PM
Ah, the good 'ole days. Take a look at the generator brushes. Their top ends should be at least 1/8" above the brush holder.

http://home.comcast.net/~jdwain/63.63.jpg
Dwain G.

motive
11-20-2006, 06:42 PM
Kid: To answer your questions:
1. After start-up the car can be revved up to 2,000 rpm and the charge circuit may or may not kick in, mostly not. Conversely, you can let the car idle at 550 rpm and after a minute or two or three, the charge will kick in without increasing rpm. SO it doesn't seem to be triggered to kick in with higher rpm.
2. Not sure about the second question, so I'll have to check it out. I'm thinking that the problem may not occur after warm re-start, but I'll check to confirm as I could be wrong.
3. With all electrical off, the ammeter shows just a slight discharge left of center during the delay period, with no movement when rpm are increased. Ammeter goes significantly farther left into discharge when lights are switched on, also with no movement when rpm are increased. Once charging, if I had a long crank period to get it started, the ammeter will move significantly right into the charge zone until the battery recovers, then it'll step down to less of a charge and remain slightly right of center thereafter, as it should.

Dwain: I'll take a look at the generator brushes, but with the generator having a full rebuild not long ago, I would think that they'd be OK. I polarized the generator when I installed it, so that shouldn't be an issue, but I'll definitely check them out. Thanks!

Mike with Speedster

John Kirchhoff
11-20-2006, 09:58 PM
Your problem sounds just like what happens when an internal regulated Delco alternator is hooked up as a one wire installation where the field coil isn't energized in the normal manner with a switched hot wire. Those guys have to be reved up considerably but once they start charging, they are basically self energized (it's initiated by the AC current) but that can't be the problem here...no AC.

If the connections aren't dirty and everything else fails, take the cover off of the regulator and on one end you will find the cutout relay. It will probably have a U shaped piece of thin metal on top and what looks like ignition points located underneith. With the engine off the points should be apart (they'd better be or you'll burn the generator up). You chould be able to push the thin metal strip down with your finger. Next to it is another coil of wire with another set of points above it with a little coil spring connected to the other end. At other end of the regulator is a second one of those guys. With the engine off, the points of both of those guys should be closed. Fire the engine up (a fast idle will help later) and if you can find a helper, have them watch the ammeter. The third set of contact points I mentioned should be closed, completing the circuit and sending juice to the generator field coil. With your helper watching, take your fingernail, popsicle stick or other non conductive material, lift the top contact. If it's charging and shows positive on the ammeter, when you lift the top point the ammeter needle should go back to 0 or discharge. If the contact point isn't closed, push it down and see if it starts charging. If it's closed and the points are clean, do the same thing with the middle set of contact points.

Without going into too much detail, let me just say that when the engine is running and the generator is producing more electricity than is being used, the U shaped points should be closed, allowing juice to flow into the battery. Under the same conditions, the other two points should be closed or opening and closing quite rapidly. At a fast idle and no appreciable electrical load, they may be closed and stay closed but at a high engine speed will be opening and closing rapidly. With the lights on, tired battery and so on, the middle one will probably stay closed and depending upon the speed and load the outside one may be dancing. The middle one controls the current (amperage) while the outside one regulates the voltage and keeps it from getting too high. I don't recommend bending the tangs on the little springs attached to the contact points because once screwed up, they're a booger to get right.

I had to do some thinking and dredge up some ancient memories before I wrote this! Keep us informed.

55studeman
11-21-2006, 02:09 AM
Interesting results. Your answers to the questions thus far rules out two ideas I had, low idle -field circuit problems and my second idea of excessive intermittent discharge at start that drains more amps than the generator can output at idle.

That second question about warm/cold may lead to the problem. The regulators are built with bi-metalic springs strips that change shape according to temperature and modify the actions of the contacts. To be frank, the new regulator are crap...they don't respond to temperature fluctations well AND when you take them apart you can't adjust them (as easily) as the older NOS regulators. My current regulator will overcharge as the temperature increases, but works great when cool-warm. I've lived with the problem for a while since it's not too critical but I plan to grab a NOS one on ebay when I have enough spare change.

John's response is good, definitely do the diagnostics he speaks of. Take a look at the shop manual, it outlines the proceedures pretty well and helps to locate problems. Just get a helper to watch the gages and to rev the engine. I've done a few of the trouble shooting excercises to track down a problem before -turned out to be a bad brush, even though it was freshly rebuilt with new ones.

Lastly, I had a peculiar discharge that was difficult to track down. At first I assumed it was the regulater just because most of the time it usually is. It turned out that after I last changed the spark plugs, I installed the battery tray over a wire and pinched it. After lots of miles, it wore through the insulation and created a short. I don't remember what wire it was but the result was an intermittent discharge and boy was it a pain to figure out. So the moral of the story is that you never know what may be the problem, however I think you are on the right track, i.e. the regulator/generator.

Keep us updated on new info or the solution.



E. West
"The Speedster Kid"
Sunny Northern California
Where the roads don't freeze over and the heat doesn't kill you.
And an open road is yours to have -only during non-commute rush hours 9am-4pm and 7pm to 7am (Ha, ha, ha)

motive
11-21-2006, 12:35 PM
Thanks for all the additional information guys. I'll perform the regulator check this week. Started the car up this morning and the delay in charging occurred once again. Revving it up did not kick it in, but normal charging commenced after a couple of minutes at idle. I shut off the car and warm re-started it several times. Each time it was restarted the normal charging was immediate. So it looks like it might be a temperature-related thing with the regulator. I'll let you know what I find this week.

Mike with Speedster.

keeffer
11-21-2006, 10:09 PM
did you polarized the new regulator after you put it in

keith kirchhoff
brockport ny 14420

motive
11-22-2006, 08:34 PM
More information on the delayed charging problem. The delay also occurs after warm re-start. I took off the regulator cover and with the engine running at idle, no accessories on, and no charging, the cut-out relay points were open and vibrating but not closing, the current and voltage points were both closed. I took a non-conductive toothbrush and closed the cut-out relay points and they remained closed and the ammeter indicated that charging was occurring. At fast idle and no appreciable electrical load the current and voltage points remained closed. At higher rpm they both remained closed! Never did I see them opening and closing rapidly. I put a voltmeter across the BAT terminal of the regulator to ground and at idle it read about 6.5 volts, at higher rpm it rose to about 7.0 volts, and the ammeter indicated a positive current of about 4 or 5 amps. This was with the regulator cover off, the hood up, and a relatively cold garage or 45 degrees F. I shut off the car and when I immediately restarted it, there was no charging and the cut-out relay points were again open. I also checked the generator brushes, or at least the upper brush that is visible without removing the generator from the car, and it extends slightly above the top of the brush holder. The commutator was a little dirty with carbon, but not bad. I cleaned it with isopropyl alcohol and Q-Tips and it cleaned up nicely. It headlights on at high rpm and with a new fully charged battery, it will charge at 2-4 amps. Any ideas now? Bad windings on regulator cut-out relay? Weak generator field? I did polarize the generator when I installed it after the rebuild.

John Kirchhoff
11-22-2006, 10:26 PM
I'll going to go at this backwards and get what I know out of the way first. A 2-4 amp excess above load is normal and probably just about right.

However, the voltage seems to be a little low, at least according to what I think. I'm sure not saying I'm right, but I feel the 6.5 volt idle voltage sounds good, but the 7 volt seems a little low. Maybe the low ambient temperature has a little something to do with it, but 45 isn't that cold. Regardless of the voltage of a battery, for it to actually increase it's charge you need at least 10% above battery voltage. For your system that's 6.6 volts and normally a 6 volt system should put out around something in the neighborhood of a regulated 7.2-7.6 volts. Unregulated, a 6 volt generator has the potential to crank out at least 8 if not 9 volts.

When it comes to charging systems, amperage isn't much without adequate voltage. On two different motorcycles, I've had one of the three windings short out. Both would make a respectable surplus amperage over what was needed, but would max out at 11.5 volts which kept the battery in a constant state of 25% charge.

The cutout relay is open when everything is shut off but when running, anything above something like 6 volts or so will close the relay, which then connects the generator to the battery. If you're idleing with a large electrical load, this will pull the system voltage below 6 volts and the relay will open. Everything is then being powered strictly from the battery and the generator isn't drawing additional juice trying to generate electricity that it can't. Rev it up, the generator begins generating unregulated voltage and when it's above 6 volts, the coil pulls the contact points shut and reconnects the charging system to the battery. This also then puts juice through the regulator where it then regulates the over production of both voltage and amperage.

Ok, now to the beginning. You said the battery is new, which is the smart thing to do when dealing with mystifying electrical problems. Does your battery have caps that allow you access to the electrolyte? If so, you may want to get a hydrometer and check the specific gravity of it to determine the charge. While the genuine high dollar hydrometers will give you a very accurate reading, the ball jobs are cheap, rather crude but will give you an idea of where you're at. As I mentioned earlier, the ammeter may be showing positive but that doesn't mean the voltage is where it should be. If the voltage is constantly low, there's a good chance the battery isn't going to be at full charge. Another way to get an idea is to check the battery voltage with your voltmeter with no load and since it's new, it should show 6-6.5 volts. This can be misleading, because a high voltage surface charge has nothing to do with the voltage under load. Then turn on all the lights, heater fan an dso on and see what it does. I'd expect it to be at 5.5 volts if the battery is at full charge but if lower, it could very well not be fully charged.

Before I go rooting around for my pre-historic shop manuals and such, I think I know a way to determine if the low voltage problem is in the regulator or generator. With the cutout relay closed, take your toothbrush and use it to close the voltage relay and keep it shut. What you're wanting to do is override the voltage control and let the generator charge as much voltage as it can. Rev the engine up with as little electrical load as possible and see what the voltage does. If it never gets above 7 volts, it must be the generator. If it gets up to 8-9 volts, the generator is ok and it must be the voltage setting on the regulator. If so, we can cover that in another one of my manifestos!

CHAMP
11-23-2006, 08:00 AM
My 48 Champion puts out 7.9 volts at fifeteen hundred R.P.M.'S.

GARY H 2DR.SEDAN 48 STUDEBAKER CHAMPION NORTHEAST MD.

motive
11-23-2006, 01:53 PM
John: I connected a voltmeter from the BAT terminal of the regulator to ground, closed the cut-out points with the toothbrush, and applied pressure across the voltage points to keep them closed and the voltage went up to at least 8 volts. So it looks like the generator is OK and I need to adjust the voltage set point of the regulator. I've been looking at the shop manual, but it tells you to install a 1/4 ohm resistor in series with the BAT circuit and then testing the voltage from BAT to Ground and then adjusting the voltage using the screw to achieve a 7.6 volt reading. Since I don't have a 1/4 ohm resistor (I can get one at Radio Shack this weekend), what voltage should I set it to without the extra resistor in the circuit, or should I wait and get one and then set it to the recommended 7.6 or a little higher? It also tells you to check and adjust the relay air gap, which doesn't sound too hard, but should I do that first? Happy Thanksgiving to All!

Mike with Speedster

John Kirchhoff
11-23-2006, 07:39 PM
Mike, a 1/4 ohm resister isn't much of a resistor at all. They may be laying around at every electronic store, but I have my doubts. Most electronic equipment uses resistors rated from hundreds to tens of thousands of ohms. Besides, I bet the resistor is supposed to simulate the voltage drop caused by load (lights, ect). It might be a good idea to check the air gap before doing anything else.

If it were my '51 with the same problem, I think I'd fire it up and let it run for a while to warm up the regulator and get the battery charged up after pulling some juice out from starting. Maybe 10 minutes or around the block? Oh, this is after it has been charging and not on vacation like it has been after starting. With all other electrical loads off, I'd screw that little black knob to get the voltage up to the 7.9 volts like Champ's car shows at about the same rpm or in that neighborhood. A few 10ths of a volt either way isn't going to be that vital. I don't know how your regulator is made, but some don't have the little knob and you instead have to bend the tab the coil spring is attaached to and it doesn't take much at all to make a difference. Either way, you're going to want to increase the tension of the coil spring because at this point, it is being too easily overcome at too low a voltage. I say to have the battery charged back up and other loads turned off because a heavy amperage load is going to pull the voltage down and would have you setting the voltage too high after the load was removed. Voltage considerably in excess of specs is going to make your lights a lot brighter but also shorten their life span. Shouldn't make much difference on your dash instruments because at least with 12 volt sytems, things like the gas guage employed a resistor to cut the voltage (to 7 volts I think?). That way the guage read accurately regardless of what the input voltage happened to be. Oh, I wouldn't adjust the current contacts at this time and then not unless you have amperage problems. Don't be concerned at this point if the ammeter seems to show a bit less than before. The higher the voltage, the lower the amperage will be at the same generator wattage output. And yes, the turkey sure was good!

John Kirchhoff
11-23-2006, 07:42 PM
Sorry, but I forgot, thanks Champ for your input in checking and reporting your car's voltage. That was quite helpful.

CHAMP
11-24-2006, 08:06 AM
You are quite welcome John. It feels good to do something right once in a while.:)

GARY H 2DR.SEDAN 48 STUDEBAKER CHAMPION NORTHEAST MD.

motive
11-25-2006, 10:40 AM
Thanks, Guys! I also appreciate your input Chanp. I'll try adjusting the voltage today. Since my problem was delayed or no charging because the cut-out relay points weren't closing, or were closing "late", will raising the voltage help with this problem, or is there something I also must do with the cut-out relay to get it working properly?

Thanks!

Mike with Speedster

John Kirchhoff
11-25-2006, 11:04 AM
While raising the voltage to where it's supposed to be is needed, I expect you'll have to adjust the cut out relay to get it to "kick in" properly. To tell you the truth, I expected this all along, but I figured it was best that you get the voltage situation straightened out first. Since my manifestos get rather long at times (how's that for an understatement!), I didn't want to throw too much at you, but I can see you're wise enough to be one step ahead of me. Once the voltage is set, you'll then want tt check the relay closing voltage. I looked at my shop manual and it shows the cut in voltage on a Champion as 6.4-6.6 volts and a Commander at 6.05-6.98 volts. The manual shows the Champion aas having an Autolite system and the Commander at Delco Remy. If you ask me, I'd say the Autolite is the better regulator when you consider the wide variation in kick in voltage of the Delco unit. But anyway, you might check the air gap first and if that's ok, then adjust the screw to get the proper kick in voltage. If it were me, I'd try for 6.1-6.5 volts. I don't know how accurate your voltmeter is, but I'd sure try to keep it below 6.5 volts. Concerning multimeters, I know a digital is more accurate but I find the analog ones do a better job of showing you what's actually happening. Kind of like the difference between a snapshot and a home movie. Good luck!

motive
11-25-2006, 01:12 PM
John: Just adjusted the voltage by bending the spring tab on the regulator, and after overshooting it a couple of times (voltage > 8.0 volts), I finally got it to 7.6 where it seemed to be operating the best. Now the charging circuit kicks in immediately, so the cut-out voltage adjustment seems OK. It now charges at about 7 amps (or a little less) at 1,500 rpm wsith no electrial load, about 1-2 amps with headlights on. Voltage drops a little with headlights on at idle, but once revved up a little it comes right back to 7.6. It was very interesting doing this adjustment, as I could easily tell if I overcorrected and the voltage was again too low, as the system wouldn't charge until the voltage got up past the cut-out voltage. So it looks like it's fixed THANKS TO EVERYONE'S HELP, especially John!
I really appreciate it.

Mike with Speedster

John Kirchhoff
11-26-2006, 06:36 PM
Glad to hear you got things in order Mike. I propbably go into too much detail at times, but if one knows how something works, it's a lot easier to figure out the problem. Enjoy your car!