I have a 1950 flathead in an 30AV8. I did the conversion from a 6V to a12V by swapping the case and field coils with a 12V case and field coils. I installed new brushes. I noticed my dash voltmeter was not showing any charging with the engine running and my battery eventually ran down. I tested the output on the car with the engine running by using a voltmeter at the jumped arm. and field terminals---no meaningful output ( using a digital meter - which may be picking up interference ). Engine quits when the ground cable is pulled from the battery at about 600 rpm. The generator will electric motor with power to the jumped arm. and field terminals. So, why will it electric motor and still not have any voltage output? Thanks for any insights! DK
You may need to polarize the system. Look in a motors or chiltons manual. They can guide you through it. FYI---depends on what system you have as to which way to polarize......make sure what you have and what you read jive together!
Even though I did it when I was a teenager motoring a generator to check it may not prove that it is good or you may have other issues and still have a good generator. If you haven't done so already I'd pull it off and take it to a generator/starter/alternator shop and have it tested. You might ask at the parts house you go to if their tester will test generators though and save some running around. If it's bad find out why, if it is good move on to the next thing on the list of things to check.
remember Fords and GMs polarize differently get out the book and do what they say assuming yours is a Ford. Lots of old timers learned on 55 Chevies and that is not how you do it on Ford.
I polarized the generator several times at the regulator as well as at the generator itself. Should I run the generator long and at a higher rpm before testing it?
Quick answer no. You should be around 14 volts at idle when check across your battery terminals. How did you polarize it? May also be a bad Voltage regulator.
I polarized it with the field lead to the Batt. lead at the regulator and then jumping the field and arm. terminal and touching the field lead with a power lead from the battery. If the field coils were not polarized and magnetized would it still run as an electric motor?
First check voltage at battery at idle and then rev it to see what it does. Probably a voltage regulator
I seems my generator is polarized in the wrong direction. It motors counter clockwise. Engine rotates clockwise. How would I repolarize the field coils in the opposite direction to get the generator to motor clockwise?
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