Question about 1985 GMC C2500

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Can an alternator drain the car battery in a few hours? I have a drain on the battery which I can not find. Everything electrical seems to check out ok. Amp gauge slowly fluctuates from 9 volts to 14 volts. I've had the local parts store check alt output and shows 13.8 volts. It sounds like the rear bearings in the alternator are rattling around a bit and alt gets hot too fast. I know I need alternator repair. Could the bridge or diode possibly go bad and drain the battery. This darn short is running me nuts....

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  • sputnik2k Apr 23, 2010

    Battery checks good. I have to take the cable off when parking.

  • fixcar001 May 11, 2010

    check the battery, does it hold charge? before you check anything elese.

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  • Master
  • 834 Answers

Yes, the internal voltage regulator can stick and drain your battery in no time at all.

Posted on Apr 22, 2010

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