Replace Brushes or the Alternator Itself

I have a 1991 Honda Accord that still has the original factory alternator in it (173k miles). The charge light came on and I took it to an auto electric shop today and he simply said it needed a new
alternator.
How does one know if all one needs is to replace the brushes or if the alternator really does need to be replaced?
Thanks,
Tim
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Remove the brush holder from the rear of the alternator (a few screws). See if the brushes are worn down past their limit. You can buy a new brush holder from the dealer (~$30), or solder on new ones yourself.
If new brushes doesn't fix the problem, you need the old alternator remanufactured.
--
Tegger

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Tegger wrote:

OR even cheaper from an auto electric supply house. The last time I bought brushes they were a buck a piece.
Failing that the regulator rectifier can go bad as well but this part is harder to get and can cost almost as much as a cheap re-built alternator.
-SP
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On Thu, 26 Apr 2007 01:09:55 +0000, Speedy Pete wrote:

Wow. On an old Celica I spent a whopping $38 to rebuild the alternator. The brushes were ~$1 each, and the regulator was $36. An afternoon with a screwdriver and a 10mm wrench and I once again had a good working alternator that lasted the rest of the life of the car (275,000 miles)
Check the bearings, too. The bearings seized on an '85 Corolla I have. I didn't replace them when I did the brushes as they were still in good shape, and now I can't get the alternator off the car!
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150-200K miles is about the life expectancy for brushes, and worn brushes are the most common cause of alternator failure. I'd go in that direction first. Be sure to disconnect the battery before removing the brush assembly!
Mike
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