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'Exciting' the alternator.

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  • 'Exciting' the alternator.

    usually a quick goose of the gas would get the alternator in the charging mode. Lately, however, I find that it takes a few - or several - high revs to accomplish this. Then it charges as normal.

    is this the beginning of a problem?

  • #2
    First I would ask how easy has it been starting the car?

    Second, I would ask, have you changed or added anything recently?

    Also, I would check the battery cable ground for corrosion. I would suggest tightening the alternator mounting bolts, or at least loosen and retighten to insure a good ground connection.

    Odds are there is nothing wrong and the battery isn't getting drained much and the alternator doesn't need to work as hard, but it is safe to check the above.
    You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!


    • Mitch
      Mitch commented
      Editing a comment
      Make sure the belt is not slipping

  • #3
    I thought you were going to tell it a rowdy story!
    Eastern Connecticut


    • #4
      Unless you start the car and let it idle for hours you should not have to worry about getting the alternator excited. Once in gear and on the road, you will hit the RPM needed to start the charge.


      • #5
        Thanks for the feedback on this.

        there is absolutely nothing new on the car, or anything done to it other than an oil change. It starts very well, just a tap on the starter and she fires right up.

        i'll check the bolts, cables and belt just to be sure, but I'm happy to hear it's unlikely to be serious.

        thanks again!


        • #6
          i'd also wonder if the belt has loosened. Are you using a cogged belt? You get a better wrap with those and less likely to slip.
          Usually a stab of the gas to about 1200 rpm will excite the field.

          The reason the 1-wire works is because the internal voltage regulator is leaky


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