dead battery

The 8.3 volts is with an analog meter. I get 6.3 with a digital meter. I also have a later model regulator on the car & not the square cad plated original. The internals are different than the blue cover ones you can buy now. I have a new blue cover VR & the quality doesn't look good. The middle coil is mounted crocked & the points don't line up well.
 

Attachments

  • VR 1.jpg
    VR 1.jpg
    68.2 KB · Views: 16
Your voltage should be 7.2 - 7.4 volts with an analog meter. Ignition interference will make a digital meter inaccurate. The voltage control will be opposite the field terminal and that is the control you want to adjust by lessening the tension on the spring by bending the spring anchor. Try another analog voltmeter? What does your analog voltmeter read connected to the battery and the engine off? 6.2 volts? Also, with engine off, using your digital meter on the ohms scale, connect one lead to the generator and the other to the frame of the regulator - should be zero ohms. If not run a ground wire between those two points - 16 ga is okay with soldered terminals and clean and tight connections. Your doing very well - good experience. As they say in the Army - learn by doing!!!! The picture you posted of the regulator - that the one you are using? You adjust that by bending the support for the flat spring.

The regulator I have on my Ford is by Borg Warner - blue cover. Try NAPA?
 
Bill, The RV I showed is the one on the car. It's built different internally than the blue covered one I have. Analog meter to battery without the engine running is now 5.9 volts & the digital is 6.2 volts. I don't have another analog I can test with. When I test with the digital meter from the generator mounting bolt to the base of the VR, I get a varying reading up to .001. The analog at the Gen bolt to the VR base is 0 ohms.
 
You need zero ohms between the generator and the regulator with a digital meter. 16 ga ground wire at zero ohms prevents erratic operation of amp gauge.

You need to adjust the voltage control closest to the Field terminal. It is absolutely necessary to polarize the generator with the battery connected positive ground. Somebody overlooked the requirement that Fords of the 6 volt are positive ground . Is the positive of the battery connected to ground and have you polarized the generator? If you have accomplished those two items, then go forward with adjusting the regulator as I have previously explained. You might consider charging the battery to 6.2 to 6.3. Will make adjusting the VR more accurate. Report back.

Bill
 
Last edited:
Bill,

I think what happened is the previous owner son put a new battery in & wasn't aware it was installed wrong. When we bought the car the battery was only 3 months old. We have a couple of Model A's & they are both Positive ground. Where do you run the wire to on the generator. My battery gauge doesn't fluctuate. It is steady. I'll change the polarity tomorrow. Thanks for your help.
 
I think you have only 2 terminals on your generator - Armature on the back plate and Field on the side. I ran my ground from the bolt that goes thru the generator to a mounting screw on the VR. I have the ammeter that was erratic and the ground wire solved the problem. And you must have zero ohms between the generator frame and the VR frame - clean and tight connections and use your digital ohmmeter - the analog meter is not that sensitive. I am of the opinion our systems are alike - two brush generator and 3 coil VR.
 
Last edited:
When cleaning voltage regulator contacts or cut out contacts NEVER, NEVER use sandpaper or emery cloth. Use fine wet and dry paper doubled over in a strip so that both contacts can be cleaned together. You can use a points file but these tend to leave a rough finish. You need to have a very smooth finish on the contacts. Then wash of contacts with a pressure pack contact cleaner and blow off gently with compressed air. Regards, Kevin.
 
Bill, I changed the battery polarity. I then removed the field wire at the VR & momentarily touched the battery terminal on the VR with the engine not running. I reconnected the field wire & ran the idle up to 1400 rpm on my meter. I had 8.5 volts on the battery with the digital meter with the engine running at 1400 rpm. With the engine off & the battery idle for a couple of minutes, I get 6.27 volts on the battery with the digital meter. Should the field relay be adjusted to lower the voltage? I don't want to fry the battery or anything else. Thanks again for you patience.
 
You need to use an analog voltmeter - a digital meter will give a false reading because of ignition interference!!

The control you need to adjust is the control that has the finer wire and will be the one closest to the field terminal on the VR. You will note that there is a spring supported by a tab or stand beneath the spring. With engine at 1500 rpm, use a pair of long nose pliers, bend that tab away from the VR to lessen the tension on the spring and that will (should) drop the voltage to 7.2 - 7.4. 8 volts is tooooo much. That will boil the battery, fry the coil and burn out bulbs. Try that let’s see what happens - hopefully it will drop to 7.2 - 7.4. Make sure the points for the field control are not stuck together - you ran sand paper thru them? If they are sticking together, install a different VR.

Bill
 
Last edited:
Bill, Is this area the arrow points to the arm to adjust? Are those contacts normally closed? I've pushed the arm in & still see 8 volts with analog meter.
 

Attachments

  • Adhustment Point.jpg
    Adhustment Point.jpg
    108.7 KB · Views: 25
That is the contact for the amount of current. Note the cross bar connecting the two controls together. You want the control to the left of your arrow - the winding on its coil is fine and adjacent to the field terminal, you want to adjust the control on the end of the VR.

Bill
 
Bill,
After trying about 10 times, I got the voltage to 7 on my analog meter with the engine running at around 1500 rpm. I checked my idle rpm & it was low at 300. I set it to 400 rpm. I know which coil to adjust now so I'll see how it does where it is. Trouble is it's getting colder & rainy out so I won't be able to do much more driving with it this season. Thanks again.
 
I would try to get the voltage to 7.2. Pleased that you had success. Originally, you mentioned a drain on the battery and I suspect that is caused by the wire to the gas and oil gauges being connected to the battery side of the ignition switch. Using your voltmeter, digital or analog, and with the ignition switch off, find the hot lead to the switch. That lead should be the only lead connected to the post on the switch. If there is another lead connected with the hot lead on the same post that extra lead needs to moved to post 3. Let’s say the hot post is the power lead from the battery and call that post #1. The next post is #2 and that lead goes to the ballast resistor. The next post is #3 and that should supply the gauges and if you find an extra lead on post #1, move it to post #3 - hopefully that solves your problem. If post #1 has only one lead that has power voltage, then I do not know what is causing the battery drain!!!??? When shutting the ignition switch off, do the gas and oil pressure guages drop to zero? On two different occasions I have experienced gauges connected to the power side of the ignition switch resulting in battery drain.

Nice working with you - enjoy your 39 Ford - still some bright and sunny days ahead.

Bill
 
Last edited:
You guessed it Bill. the battery terminal has 3 wires on it & the gauge & coil have 1 wire. One of the wires on the battery terminal is the sport light which does not need to be on there. I need to see where the other wire goes. Thanks for the heads up.
 
I'm still playing with this dim light situation. I do think I need to get a little more charging voltage from the regulator. I have removed the dimmer switch completely & taken the wires off it. There are no shorts & there is proper continuity at hi beam or low beam. I disconnected the headlamp wires at both fenders. I have 6 volts at the battery. The battery voltage at the wire terminal that goes to the dimmer has 5.6 volts on it. I hook each of the 3 wires back onto the dimmer switch & check each terminal as I put the wires back onto the dimmer & I still have 5.6 volts. I put all new connectors on the 3 wires for the head light on the driver side. As I plug each wire together the voltage starts to drop. With all 3 connected I have 5 volts on all terminals on the dimmer switch. I hooked up the 3 head light wires on the passenger side without changing the wire connectors & now I'm at 4.6 volts. Tells me there isn't much sense in changing the connectors for those 3 wires when the voltage is slowly dropping as I connect the head light wires. With all the head light wires disconnected I check ground to the head light wires & all have good grounds. The headlights are slightly better than when I started but still not as bright as the ones on our Model A. I checked voltage at the head light socket on the Model A & have 6.3 volts. That's almost 2 volts more than the 39 has.
 
Wow - reversed the polarity! Now that you have sorted it out, remember it never hurts to pull the cable or use a battery disconnect when its garaged.
 
Back
Top