irregular voltage regulator

H

hueyhoolihan

Well-known member
i've done two multimeter battery tests on my new Optima 6v battery. with the engine NOT running, i get about 6.5v. that seems reasonable...but with it running (which i assume reflects the charging voltage coming through the voltage regulator) i get 10-11v. which seems excessive.

...wondering if the previous owner who had had an 8v battery installed, also tweaked the voltage regulator (American Bosch Inc. 6v Positive) to let 10-11v through in order to charge the 8v battery. although even an 8v shouldn't need THAT much voltage to charge.

that has been the extent of the re-charging system testing as of yet.

what say ye?
 
hueyhoolihan said:
i've done two multimeter battery tests on my new Optima 6v battery. with the engine NOT running, i get about 6.5v. that seems reasonable...but with it running (which i assume reflects the charging voltage coming through the voltage regulator) i get 10-11v. which seems excessive.

...wondering if the previous owner who had had an 8v battery installed, also tweaked the voltage regulator (American Bosch Inc. 6v Positive) to let 10-11v through in order to charge the 8v battery. although even an 8v shouldn't need THAT much voltage to charge.

that has been the extent of the re-charging system testing as of yet.

what say ye?
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I'm not an EE, but have a good friend who is. I had a similar situation with a solar boat battery charger several years ago. After hooking it up, I decided to check the output voltage of the solar panel. To my surprise, it was about 23 volts. I asked my friend about this, and he said it was no problem, as that was the "open circuit voltage" put out by the panel when it had no load on it. Since the panel was a low-amperage device, the battery would easily absorb the excess voltage from the panel with no problem. We hooked the battery up to the panel and it had pulled the panel voltage down to 13.5 volts.

I believe that you still have problem. The solar panel was low amperage (100 ma) device and the battery could easily absorb the excess voltage (100ma X 10 volts=1 watt). An automobile generator is a different animal with old Ford units capable of as much as 30 AMPs. I think you are absolutely correct about the previous owner "tweaking" the voltage regulator to support the 8 volt battery. At that much of an increase, the voltage regulator is operating at the limits of its capability, and it's probably as close as it gets.

You could get an old Motor Manual or similar and try to readjust the voltage regulator. I've had trouble with new voltage regulators and would have more faith in an old one that's still running but out of adjustment than a new one from the FLAPS. I can't think of anything else that would need to be changed or adjusted.
 
not sure that the one in question is original. its a lovely black crinkled finish affair with a nice red label that reads, in part: "American Bosch Inc. 6 volt positive only", or something along those lines.

anyway i'm more concerned that if i'm right about the tweaking, that i may have damaged my one day old Optima battery. wouldn't THAT be shame, ...eh? :(

so tomorrow i'll probably just be buying one of those 6v regulators made by Standard. probably at O'Reilly's. unless someone convinces me in the mean time that the 10v-11v's i'm reading on my multimeter connected at both ends to the terminals with the car running is normal.
 
When you put additional voltage into a battery at a high amperage rate, the excess energy the battery can't absorb is turned into heat. A 30 amp overcharge at 5 volts has the potential of generating 150 watts. I don't think that much heat can do any substantial damage over a short period of time, but things will be different if it would go on for multiple hours. Overcharging has "boiled" and ruined batteries, and even started fires in the past, but it usually took many hours.
 
tubman said:
When you put additional voltage into a battery at a high amperage rate, the excess energy the battery can't absorb is turned into heat. A 30 amp overcharge at 5 volts has the potential of generating 150 watts. I don't think that much heat can do any substantial damage over a short period of time, but things will be different if it would go on for multiple hours. Overcharging has "boiled" and ruined batteries, and even started fires in the past, but it usually took many hours.
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well that's reassuring. as i had the engine mostly idling for maybe 20 minutes at most.
 
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You are using an analog voltmeter - right? Most people are aware that using a digital voltmeter on these old cars will often give an erroneous reading when the car is running.
 
The voltage output should be no more than 7.2 volts. If the voltage gets too high then the light bulbs will start burning out due to excess voltage. Adjusting the tension on the voltage regulator pole can be tricky so a person needs to research the process in order to be successful at it. It functions by rapidly opening and closing the charging circuit. It makes a buzzing sound if the engine isn't so loud as to drown out the sound of it.

If you have a local auto electric shop, you may consider asking them to do the job.
 
rotorwrench said:
The voltage output should be no more than 7.2 volts. If the voltage gets too high then the light bulbs will start burning out due to excess voltage. Adjusting the tension on the voltage regulator pole can be tricky so a person needs to research the process in order to be successful at it. It functions by rapidly opening and closing the charging circuit. It makes a buzzing sound if the engine isn't so loud as to drown out the sound of it.

If you have a local auto electric shop, you may consider asking them to do the job.
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thank you for the information! :)

i've decided to buy a new 6v regulator suitable for a 1941 ford. the beautiful black-crinkle-finished-red-labeled American Bosch Inc. one that came with the car that was probably hacked by a previous owner to work with the 8v battery that was also in the car when purchased, assuming a test of the new one when installed today proves satisfactory, will soon be in the trash. :)
 
my suspicions turned out to be true...

a previous owner, or possibly even the consigner, had not only installed an 8v battery but had modified the voltage regulator (albeit inaccurately) in an attempt to force it to charge the battery.

before the new regulator (as of yesterday) i was getting over 10v at the battery (a 6v Optima battery) and now with the new voltage regular i'm getting about 7v. which is as it should be. the amp gauge is now reading a more normal amount of charging too.
 
Use an analog voltmeter not digital to check. When running the flathead will produce lots of electrical noise effecting a digital voltmeter and giving incorrect readings.
 
My Harbor Freight digital voltmeter goes nuts when used around my running '41 electrical system! Yes, I do have a trusty analog meter to use.
 
If anyone has a good description of how to adjust the inner points of a Ford voltage regulator, I’d love to see it. I have a 1957 Motors manual, but the description of adjusting is not very thorough. Also requires a couple go/no-go feeler gauges which I don’t have.
 
Had a voltage regulator once that was causing a discharge situation. Removed the cover, and it worked fine. Ended up putting a plastic food storage container on it until I got a new regulator. Go figure....electricity is funny stuff.
 
I recommend purchasing this Ford booklet. Reprints are available from some vendors (sorry, I forget which one I bought it from). It provides good, detailed information on repair and adjustment.
 

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ndnchf said:
I recommend purchasing this Ford booklet. Reprints are available from some vendors (sorry, I forget which one I bought it from). It provides good, detailed information on repair and adjustment.
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Bunch of these currently on Epay. Just ordered one ;)
 
I has the same issue now on one of my Ferguson tractors from the 40’s with Continental engines and positive ground 6V system.
This is Lucas UK parts and 2 coils inside.
It charge out ca 20 volts and it actually burned the insulation in the generator.
I use a mulimeter to test this.
The red light do light when ignition is on and do not go off when motor is running.
Thats wrong.
I tested 3 others regulators but was told this units easy gets bad if a tractor has been out or not been used for years.
I know generator is working again as I made a new isulator in cap and it charge to much volt.

My other Ferguson 48 tractor do work and red ligh go off in running engine snd it chages out 7.2 volt.
I use a 70 AMP std battery ( not Optima ) in this tractors.

As all parts is old and numbered parts on month/years I would like if possible to use the std regulator.
But I try to check points, and I try to adjust the shatter coil but no luck.

I will try get it tested but few shops or people know this stuff.
As a mechanical part, is there shops that do restore them ?
If, ideas to find them, I can send US or UK etc.

—-/——

In my 32 coupe I will use a 40’s style generator and I found a old Ford/Mercury regulator.
Both starter, generator is restored and I plan use a Optima battery here instead.
 

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3W Hank said:
I has the same issue now on one of my Ferguson tractors from the 40’s with Continental engines and positive ground 6V system.
This is Lucas UK parts and 2 coils inside.
It charge out ca 20 volts and it actually burned the insulation in the generator.
I use a mulimeter to test this.
The red light do light when ignition is on and do not go off when motor is running.
Thats wrong.
I tested 3 others regulators but was told this units easy gets bad if a tractor has been out or not been used for years.
I know generator is working again as I made a new isulator in cap and it charge to much volt.

My other Ferguson 48 tractor do work and red ligh go off in running engine snd it chages out 7.2 volt.
I use a 70 AMP std battery ( not Optima ) in this tractors.

As all parts is old and numbered parts on month/years I would like if possible to use the std regulator.
But I try to check points, and I try to adjust the shatter coil but no luck.

I will try get it tested but few shops or people know this stuff.
As a mechanical part, is there shops that do restore them ?
If, ideas to find them, I can send US or UK etc.

—-/——

In my 32 coupe I will use a 40’s style generator and I found a old Ford/Mercury regulator.
Both starter, generator is restored and I plan use a Optima battery here instead.
Click to expand...
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