The Ford Barn

40ford · 02-01-2017, 09:44 AM

The battery gauge on my 40 used to read correctly when driving I thought.It used to read in the green area going about 55mph down the road.Now when I turn the switch on and crank the car it goes to middle at line between the red and yellow area and stays there.It makes no difference if car is just sitting or going 55mph.Car still cranks good and lights work good with no show of a discharge?Is this normal or is something going on?The car is all stock with 6 volt system.

19Fordy · 02-01-2017, 10:52 AM

[B]In the original 1940 FORD owners manual it says on page 16:

"The Battery Gauge indicates the voltage of the battery and generator circuit. It is a protection against damage in the event of failure of the generator or regulator. The pointer should not at any time read above the green sector. After turning on the ignition switch and before starting the engine, the pointer should rise at least to the orange sector if the battery is fully charged. In the event the indicator fails to reach this point after waiting approximately one minute, have your dealer check the condition of the battery. Under normal driving conditions and with no load except the ignition current, the pointer should rise to and remain within the green sector."

I remember that when my 40 was 6V that's the way the BATT gauge read.

Ken/Alabama · 02-01-2017, 02:18 PM

Try putting a jumper wire on the back of the ignition switch from the batt connection to the gauge connection. If the switch is dirty or burned it could be causing a high resistance creating a low reading on the batt gauge.

flatheadmurre · 02-01-2017, 02:23 PM

Why not measure the battery voltage before and with the engine started ?
That will give you an indication of battery status and if the car is charging.
If it is charging as it should next would be to follow Kens advice and check the ignition switch for voltage drop there.

40ford · 02-01-2017, 03:45 PM

I checked the voltage at battery with car not running and it was 6.33 volts.I cranked car and running at high rpms and the reading at battery was 6.24???I keep thinking it is my generator.

flatheadmurre · 02-01-2017, 03:52 PM

Sponsored Links (Register now to hide all advertisements)

You have to test generator/regulator can be either of them.

Ken/Alabama · 02-01-2017, 08:25 PM

Quote:

Originally Posted by 40ford

I checked the voltage at battery with car not running and it was 6.33 volts.I cranked car and running at high rpms and the reading at battery was 6.24???I keep thinking it is my generator.

It could be the regulator. If you ground the field wire while the engine is running the generator will put out max charge and sent the batt gauge beyond the green band. But don't run it long like that. That will tell you if your gen is working.

flatheadmurre · 02-02-2017, 12:44 AM

Quote:

Originally Posted by Ken/Alabama

It could be the regulator. If you ground the field wire while the engine is running the generator will put out max charge and sent the batt gauge beyond the green band. But don't run it long like that. That will tell you if your gen is working.

Ford generators need voltage applied to field not grounding.
Type A generators with separate field needs voltage.
Type B generators ( self exiting) needs grounding.

40ford · 02-02-2017, 11:28 AM

Quote:

Originally Posted by Ken/Alabama

It could be the regulator. If you ground the field wire while the engine is running the generator will put out max charge and sent the batt gauge beyond the green band. But don't run it long like that. That will tell you if your gen is working.

Ken I tried that and got no results at all.Seems like generator is not doing the job?

flatheadmurre · 02-02-2017, 11:39 AM

If you grounded it you get no result...grounding works on goverment motor cars...not ford.

Ken/Alabama · 02-02-2017, 12:44 PM

Quote:

Originally Posted by flatheadmurre

If you grounded it you get no result...grounding works on goverment motor cars...not ford.

I've used this troubleshooting method many times over the last 30 years and every time it was on either mine or a friends 39-50 Ford.

flatheadmurre · 02-02-2017, 12:57 PM

Quote:

Originally Posted by Ken/Alabama

I've used this troubleshooting method many times over the last 30 years and every time it was on either mine or a friends 39-50 Ford.

Ok i might be wrong about configuration of it then.

flatheadmurre · 02-02-2017, 01:06 PM

Easy to check...if one wire of the fields are hooked up to the brushes you have a generator that needs grounding to charge.
If one end of the fields are hooked up to housing/ground you have a generator that needs voltage aplied to charge.

flatheadmurre · 02-02-2017, 01:18 PM

Had to walk down to the shop and split a generator...thinking my mind was slipping badly.
The fields are grounded in one end as i thought so you need to aply voltage to the F terminal to make it charge.
Grounding the field winding in both ends will give you no effect.
Not trying to pick a fight just trying to help here.

02-01-2017, 09:44 AM	#1
40ford Senior Member Join Date: May 2010 Location: Cherryville,N.C. Posts: 535	40 Charging Problems: The battery gauge on my 40 used to read correctly when driving I thought.It used to read in the green area going about 55mph down the road.Now when I turn the switch on and crank the car it goes to middle at line between the red and yellow area and stays there.It makes no difference if car is just sitting or going 55mph.Car still cranks good and lights work good with no show of a discharge?Is this normal or is something going on?The car is all stock with 6 volt system.

02-01-2017, 10:52 AM	#2
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,933	Re: 40 Charging Problems: [B]In the original 1940 FORD owners manual it says on page 16: "The Battery Gauge indicates the voltage of the battery and generator circuit. It is a protection against damage in the event of failure of the generator or regulator. The pointer should not at any time read above the green sector. After turning on the ignition switch and before starting the engine, the pointer should rise at least to the orange sector if the battery is fully charged. In the event the indicator fails to reach this point after waiting approximately one minute, have your dealer check the condition of the battery. Under normal driving conditions and with no load except the ignition current, the pointer should rise to and remain within the green sector." I remember that when my 40 was 6V that's the way the BATT gauge read.

02-01-2017, 02:18 PM	#3
Ken/Alabama Senior Member Join Date: May 2010 Location: Alabama Posts: 3,259	Re: 40 Charging Problems: Try putting a jumper wire on the back of the ignition switch from the batt connection to the gauge connection. If the switch is dirty or burned it could be causing a high resistance creating a low reading on the batt gauge.

02-01-2017, 02:23 PM	#4
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 40 Charging Problems: Why not measure the battery voltage before and with the engine started ? That will give you an indication of battery status and if the car is charging. If it is charging as it should next would be to follow Kens advice and check the ignition switch for voltage drop there.

02-01-2017, 03:45 PM	#5
40ford Senior Member Join Date: May 2010 Location: Cherryville,N.C. Posts: 535	Re: 40 Charging Problems: I checked the voltage at battery with car not running and it was 6.33 volts.I cranked car and running at high rpms and the reading at battery was 6.24???I keep thinking it is my generator.

02-01-2017, 03:52 PM	#6
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 40 Charging Problems: Sponsored Links (Register now to hide all advertisements) You have to test generator/regulator can be either of them.

02-02-2017, 11:39 AM	#10
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 40 Charging Problems: If you grounded it you get no result...grounding works on goverment motor cars...not ford.

02-02-2017, 01:06 PM	#13
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 40 Charging Problems: Easy to check...if one wire of the fields are hooked up to the brushes you have a generator that needs grounding to charge. If one end of the fields are hooked up to housing/ground you have a generator that needs voltage aplied to charge.

02-02-2017, 01:18 PM	#14
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 40 Charging Problems: Had to walk down to the shop and split a generator...thinking my mind was slipping badly. The fields are grounded in one end as i thought so you need to aply voltage to the F terminal to make it charge. Grounding the field winding in both ends will give you no effect. Not trying to pick a fight just trying to help here.