CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

1993 Chevrolet Caprice Alternator Problem?

Hi,



The battery light stayed on after I started my Caprice (74k miles) this morning. The battery voltage was 11.9 V, with the engine running it was 11.55 V. The battery and alternator connections are clean and tight. I believe the voltage regulator is built into the alternator



I’m guessing it’s the alternator, but I’m open to suggestions. I’ll have it tested at Advance or Autozone before I start throwing parts at the car. Any recommendations for a replacement, i.e. Napa, Autolite, etc? There is an alternator repair shop around here so I may look into that too.



Thanks,



Ed

I’ll have it tested at Advance or Autozone before I start throwing parts at the car.

And then you will know far more accurately what is wrong than we can tell you without that information. It does sound like a charging system problem, but you should find out when you have it tested.

The rebuilds are questionable. Other than that, I would not worry.

I would like to clarify the above comment. A good shop can rebuild it well. The questionable rebuilds are those that most auto part stores use. Then have a lot of failures. They replace them, but they only replace the part, not the labor to install it.

You might be considerably better off with a local rebuild shop. You might only need to replace brushes. With a badly rebuilt unit from an auto parts store, you have to go through replacing it twice. At a repair shop they will probably do a better job at bench testing.

Good idea, I’ll try the local repair shop first. Everybody’s closed for New Years, so I won’t find out till next week. I’ll post back with the diagnosis.

Thanks,

Ed

Just wanted to follow up. It took about 10 minutes to remove the old alternator. Based on both of your replies I decided to go to the local shop. It was a few dollars more, but he uses GM OEM parts for the refurb. He also took the time to switch over the original pulley to the rebuilt alternator.

There were no problems installing the alternator. I took the car for a long ride and it ran like a champ. The alternator’s putting out good voltage and isn’t getting hot. The belt and pulley are quiet.

Thanks for the advice,

Ed B.