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Old 09-04-2017, 11:36 AM   #1
DJ S
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Default Generator Producing too much voltage

As the title says, the car is producing a much higher voltage than it should. Instead of charging 6v, it's charging upwards toward 10-11 volts. The problem was discovered when the car kept burning out stop light bulbs. It is charging 5-6 amps however. 6v gnerator, stock cut-out, 6v battery, recently cleaned ground connections, and we still can't determine the cause.
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Old 09-04-2017, 02:58 PM   #2
Bob C
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Default Re: Generator Producing too much voltage

sounds like a bad connection between the generator and battery, could be ground
or hot side.

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Old 09-04-2017, 05:02 PM   #3
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Default Re: Generator Producing too much voltage

X 2 on post 2.
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Old 09-04-2017, 05:28 PM   #4
Kevin in NJ
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Default Re: Generator Producing too much voltage

The battery is the voltage regulator for the car. If there is a resistance between the battery and the terminal at the starter then there will be a higher voltage. Keep in mind you need to include the ground.
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Old 09-04-2017, 09:29 PM   #5
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Default Re: Generator Producing too much voltage

With engine running, put the one lead of your voltmeter on the ground post of the battery. Use the other lead to check voltage on: 1. Frame, should be zero. 2. Engine block, should be zero. 3. Generator case, again should be zero. NEXT, put the voltmeter lead on the negative (power) post of the battery. 1. Use the other lead to check from the battery all the way forward to the generator cutout, as you move forward, as soon as you see voltage, between that and the last place you checked is where the problem is.
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Old 09-04-2017, 11:01 PM   #6
Mike V. Florida
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Default Re: Generator Producing too much voltage

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As stated, bad connection, bad battery. There are voltage regulators for the generators.

Tom Wesenberg sells one.

There is one that replaces the cover (not really sure if they are still being sold) by James Peterson.

and then there is one inside of the what looks like the cutout sold by Fun products
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Old 09-04-2017, 11:45 PM   #7
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Default Re: Generator Producing too much voltage

I had that problem with a model A that I recently bought. I don't think the prior owner even knew about it because he never drove it at night. When I first did, the lights were very dim with the car off, and once the car started, Wham! The lights came up very bright and blew one of them out. The source was a high resistance connection at the back of the ammeter in the dash. It was the crimp-on connector on the wire for the lug going to the meter. It was so bad that it had gotten hot and had corroded the terminal over time.

I soldered a new connection on and bought a new (crappy) ammeter. The old one was also a crappy repop.

It is important to note that as others have said, the high resistance or bad connection can be anywhere in the battery and charging circuit. My example was just one of several possible points.

I have no idea how long the prior owner had this going on, but by the looks of the connector, it had to be a while.

Last edited by Magicbox51; 09-05-2017 at 12:54 AM.
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