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Old 08-15-2020, 07:12 PM   #1
sofield
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Default Alternator over charges

Alternator puts out 20 amps with a full charged battery. What's the cause
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Old 08-15-2020, 08:22 PM   #2
Chuck Sea/Tac
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Default Re: Alternator over charges

Loose connections somewhere, maybe faulty regulator. Bad battery.
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Old 08-15-2020, 10:39 PM   #3
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Default Re: Alternator over charges

You need to do a voltage check in order to help us troubleshoot the issue. Do the check directly on the battery and another right at the alternator. Get back with the data.
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Old 08-16-2020, 08:52 AM   #4
Patrick L.
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Default Re: Alternator over charges

Does it have the 'D' slot to bypass the regulator ? If so, do it and see if the charge rate changes. That is I'm assuming yours has an internal regulator. If it has an external one then bypass it and take a look.
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Old 08-16-2020, 08:54 AM   #5
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Default Re: Alternator over charges

Check ground between alt and battery post.
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Old 08-16-2020, 11:09 AM   #6
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Default Re: Alternator over charges

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As mentioned, always check all the wires and connections first. A high resistance connection is a load just like a resistor so it will get hot and draw unnecessary current. The battery should be load tested, charged, and serviced unless it is a non service type. In any case it should maintain rated voltage well after charging.

If everything checks OK then it's time to think about an alternator repair or replacement. The solid state internal alternator controllers should keep voltage right on spec and current should be minimal after the battery is changed back up from starting the engine.
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Old 08-16-2020, 11:30 AM   #7
Marshall V. Daut
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Default Re: Alternator over charges

Check your "Private Messages" in the top right corner of this webpage.
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Old 08-16-2020, 12:17 PM   #8
Tom Endy
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Default Re: Alternator over charges

My suggestion is to clean the connection where the battery ground cable attaches to the frame. It is out of sight and hard to access. It is the most neglected electrical connection on a Model A.

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