The Ford Barn

47topless · 01-11-2026, 06:28 PM

I just installed a new battery in my 59AB. Car starts right up but, on acceleration, the amp meter is buried to the positive side. I am afraid to drive this car to see if that auto corrects after a while.
Is this normal or is my generator producing too much current?
Thank you,
Mr. pair uh noid

1942deluxe · 01-11-2026, 06:36 PM

Not normal in my opinion. Regulator problem?

koates · 01-11-2026, 07:00 PM

With some revs up check the voltage at the A or Batt terminal on the voltage regulator. Should be 7.5 volts with your multimeter set to DC volts. Report back your findings. Regards, Kevin.

47topless · 01-11-2026, 07:34 PM

I am getting 5.9 at idle and 8.0 with a rev

rotorwrench · 01-11-2026, 09:20 PM

On a new battery, it should be top charged for a few hours to ensure low load on the generator. The battery voltage should be a bit more than 6-volts. Normal would be around 6.2 volts at rest. If the vehicle has set up for long period then the generator field should be flashed to insure good pole shoe residual magnetism with proper polarity. All the old 6-volt vehicles have positive ground after the model T era. Be sure all related electrical connections are clean and secure.

koates · 01-11-2026, 09:29 PM

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8 volts is only a touch high , so maybe the voltage reg could be adjusted down a little. If you dont know how to do that may I suggest that you take it to an auto electrician. Original ford service bulletins show how to do it. Your new battery may not have been fully charged and so the ammeter may show a high charge for a while until it charges up. Maybe leave it for a while and see if the ammeter drops back. Regards, Kevin.

47topless · 01-11-2026, 09:46 PM

Thank you guys. Good advice.

Ernstudet22 · 01-12-2026, 10:41 AM

Is it possible your battery, although being new, wasn't fully charged?

47topless · 01-12-2026, 10:56 AM

After installing the battery, I connected it to my charger, and it read "FULL". It now measures 6.2 V so I believe that it is fully charged.
I will recheck this AM.
Driving this car around a bit may bring the needle down. I'll try that and if no luck, I have another regulator to try.
Thanks for the response.
"It's always something!".

1942deluxe · 01-12-2026, 11:34 AM

Take the cover off the regulator and inspect the points. Saw one where they were "smoked".

farmertom · 01-12-2026, 12:42 PM

Quote:

Originally Posted by 47topless

After installing the battery, I connected it to my charger, and it read "FULL". It now measures 6.2 V so I believe that it is fully charged.
I will recheck this AM.
Driving this car around a bit may bring the needle down. I'll try that and if no luck, I have another regulator to try.
Thanks for the response.
"It's always something!".

a fully charged 6v battery should read 6.37 v .

01-11-2026, 06:28 PM	#1
47topless Senior Member Join Date: Jun 2022 Location: Northern Colorado Posts: 496	ampmeter buried positive on acceleration I just installed a new battery in my 59AB. Car starts right up but, on acceleration, the amp meter is buried to the positive side. I am afraid to drive this car to see if that auto corrects after a while. Is this normal or is my generator producing too much current? Thank you, Mr. pair uh noid

01-11-2026, 06:36 PM	#2
1942deluxe Senior Member Join Date: Jan 2011 Location: Albion, PA Posts: 1,100	Re: ampmeter buried positive on acceleration Not normal in my opinion. Regulator problem?

01-11-2026, 07:00 PM	#3
koates Senior Member Join Date: May 2010 Location: Melbourne Australia. Posts: 2,218	Re: ampmeter buried positive on acceleration With some revs up check the voltage at the A or Batt terminal on the voltage regulator. Should be 7.5 volts with your multimeter set to DC volts. Report back your findings. Regards, Kevin.

01-11-2026, 07:34 PM	#4
47topless Senior Member Join Date: Jun 2022 Location: Northern Colorado Posts: 496	Re: ampmeter buried positive on acceleration I am getting 5.9 at idle and 8.0 with a rev

01-11-2026, 09:20 PM	#5
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 18,006	Re: ampmeter buried positive on acceleration On a new battery, it should be top charged for a few hours to ensure low load on the generator. The battery voltage should be a bit more than 6-volts. Normal would be around 6.2 volts at rest. If the vehicle has set up for long period then the generator field should be flashed to insure good pole shoe residual magnetism with proper polarity. All the old 6-volt vehicles have positive ground after the model T era. Be sure all related electrical connections are clean and secure.

01-11-2026, 09:29 PM	#6
koates Senior Member Join Date: May 2010 Location: Melbourne Australia. Posts: 2,218	Re: ampmeter buried positive on acceleration Sponsored Links (Register now to hide all advertisements) 8 volts is only a touch high , so maybe the voltage reg could be adjusted down a little. If you dont know how to do that may I suggest that you take it to an auto electrician. Original ford service bulletins show how to do it. Your new battery may not have been fully charged and so the ammeter may show a high charge for a while until it charges up. Maybe leave it for a while and see if the ammeter drops back. Regards, Kevin.

01-11-2026, 09:46 PM	#7
47topless Senior Member Join Date: Jun 2022 Location: Northern Colorado Posts: 496	Re: ampmeter buried positive on acceleration Thank you guys. Good advice.

01-12-2026, 10:41 AM	#8
Ernstudet22 Junior Member Join Date: Nov 2018 Posts: 21	Re: ampmeter buried positive on acceleration Is it possible your battery, although being new, wasn't fully charged?

01-12-2026, 10:56 AM	#9
47topless Senior Member Join Date: Jun 2022 Location: Northern Colorado Posts: 496	Re: ampmeter buried positive on acceleration After installing the battery, I connected it to my charger, and it read "FULL". It now measures 6.2 V so I believe that it is fully charged. I will recheck this AM. Driving this car around a bit may bring the needle down. I'll try that and if no luck, I have another regulator to try. Thanks for the response. "It's always something!".

01-12-2026, 11:34 AM	#10
1942deluxe Senior Member Join Date: Jan 2011 Location: Albion, PA Posts: 1,100	Re: ampmeter buried positive on acceleration Take the cover off the regulator and inspect the points. Saw one where they were "smoked".