I thought I would post this up in case anyone runs into the problem I had with the charging system on my Coronet.

Last week while driving on the interstate I noticed my ammeter was discharging. When I down shifted it would begin charging again. I got it home ok and the next day went to diagnose it. Started the car and could not duplicate the problem. Then when it got to operating temp it started again. Discharge to around 2000 rpm then over to charge.

I did the usual tests and even pulled the alternator and bench tested it. Everything checked out. Next day car gets warm and same thing happens. This time I pull the alternator which is the original for the car and decided to pull the brushes.

When I pulled the field brush I noticed the holder had cracked and come apart. I pulled one off a spare alternator and put it back together and problem solved. I assume it was making intermittent contact. Why only at low RPM and when warm I am not sure.

Here is a pic of the offending part. This small part caused a large quantity of beer to be consumed over the last few days.

If you posted this at the time can you pull it up w a link