Question about 1991 Jeep Wrangler

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1991 jeep wrangler: alternator overcharging

I have a 1991 jeep wrangler straight 6, 5 speed. alternator is overcharging the battery. the alternator is brand new. can anyone help me?

Posted by Anonymous on

  • Anonymous Jul 06, 2009

    i knew the voltage regulator was inside the alternator but i already replaced the alternator and i'm still having the same problem. i know there's a chance this second one is bad too but it's a small chance. would it be possible i have a short somewhere?



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It sounds as the voltage regulator which is built into the back of the alternator has stuck. Occaisionally this even happens on new ones. Would suggest taking the alternator back as it shoud be under warranty.

Posted on Jul 06, 2009

  • Anonymous Jul 07, 2009

    Normally if you have a short in the circuitry it will pull down the voltage not increase it. I would check at the battery with a voltmeter and see what the indication is there. While at a normal idle if it is putting out more than 13.8 volts it is probably the voltage regulator. If the charging rate is in the acceptable range 12-14 volts at the battery the problem may lie in your gauge.



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