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**mr48chev** · 03-16-2009, 11:56 PM

It sounds like it might be a bad diode in the alternator.
That would cause an unexplained drain like that.

Another thing that can cause a battery drain is a dirty top on the battery that allows current to flow across the top of the battery. Take your volt meter and hold one lead on the appropriate post of the battery and touch the other to various spots on the top of the battery. See if there is any reading. I have seen as much as eight volts flow across the top of a dirty battery. The cure is to clean it off.

The 70 will have an external regulator unless the alternator has been changed.

03-16-2009, 11:56 PM	#8
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,839	Re: drain on battery It sounds like it might be a bad diode in the alternator. That would cause an unexplained drain like that. Another thing that can cause a battery drain is a dirty top on the battery that allows current to flow across the top of the battery. Take your volt meter and hold one lead on the appropriate post of the battery and touch the other to various spots on the top of the battery. See if there is any reading. I have seen as much as eight volts flow across the top of a dirty battery. The cure is to clean it off. The 70 will have an external regulator unless the alternator has been changed.