Generator not charging-where to start?

Turn lights on, does ammeter show discharge ?

Loosen belt, fed power to generator, does it motor slowly ? If it does the generator should be good. If not, it has a problem.

That leaves the regulator. What type are you using ?
 
I did turn on lights and it did discharge.
Will have to do belt tomorrow.
Will check regulator in AM also.
Thank you
 
If you rev the car do the lights go slightly brighter? if so the generator is working [ but not necessarily the converse!]
 
If you have a regulator in the cutout can, jumping across it will ruin it. How about using a voltmeter and checking battery voltage before you start the car, then again when its running. Also check voltage on each side of the cutout.
 
We need to know which type of generator for one. Get to know your charging system. It's one of the more simple systems ever offered by Ford. The type of reverse current protection also needs to be identified for us to give accurate answers, ie OEM type cut out relay, diode made to look like a cut out, or whether it has a Fun Projects regulator or some other regulator like the ones that attach to the cover band.

If it has an alternator then that is a whole different story.

Ford's old generators functioned off of residual magnetism until it made enough current for it to come on line. It essentially makes its own current that is regulated by the third brush. Voltage is held within normal range by the battery.
 
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Use a voltmeter. Set your multimeter to the DC volt scale. The 20 volt scale should be fine. Run the engine at a fast idle, about 1,000 rpm. Measure the voltage at the generator stud, opposite side of the cutout from where the wires hook up. You should see either about 7 volts or 14 volts depending on whether you have a 6 volt or 12 volt system. If that is OK then measure again at the wire side of the cutout. If this is at the battery voltage then the cutout is bad. The generator can be putting out much more that the 7 or 14 volts if it is not connected to the battery. If this is the case, do not run the engine very long, just half a minute or so, or you stand the chance of burning out the generator. If the generator is less than 7 or 14 volts, then it is bad or the third brush is not adjusted correctly.

Also check all the wiring to make sure that there are no open circuits or short circuits. You can use the ohm scale on your multimeter.

A good site for all things electrical on a Model A is https://www.mafca.com/downloads/Seminars/2018%20Reno%20Electrical%20System%20Alex%20Janke.pdf
 
Well I got it working. Don’t know how,but I will give what I did.
I did take off the fan belt and jumped the cutout. Generator did”motor” great. Put fan belt back on, started engine, and wow, it did charge on the amp meter. Not very high. So I then moved the third brush down, and wow, 10 amps.
So don’t know what made it work, but is OK now.
Thanks guys for the ideas.
 
Fred K-OR said:
Well I got it working. Don’t know how,but I will give what I did.
I did take off the fan belt and jumped the cutout. Generator did”motor” great. Put fan belt back on, started engine, and wow, it did charge on the amp meter. Not very high. So I then moved the third brush down, and wow, 10 amps.
So don’t know what made it work, but is OK now.
Thanks guys for the ideas.
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Don't know why it wasn't charging before, but, it appears it just needed polarizing. Motoring it and jumping the cut-out did that.
 
10-amps is a bit high for summer months unless you run at night some. There is a winter time adjustment that Ford recommended in a service bulletin. They generally used a calibrated master amp meter to adjust them to 10 to 12 amps for wintertime service at the Ford Dealers of the time.

Your checks there may have improved the ground path back to the engine unless the pole shoe residual magnetism was a bit weak before motoring.
 
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