Alternator problems

[cmichaelo]

My alternator produces 14.9V at idle rpm. Also the interior lights are flickering. Isn't 14.9V too much?

And the other day, the alternator produced only 12V, then slowly dropped down to close to 10V, and then the car just stopped running. (Note, I had lights and fog lights on and battery is only 2y old.)

I had the alternator rebuilt 4 years ago.

Is it time for a rebuild again, or should I just replace the regulator?

 

[Dan H]

If I remember correctly the alternator should put out over 14.5 volts but somewhere nearing 15 is too much.

I will see if I can find the specs.

 

[cmichaelo]

I did a search on the SHOForum here and found a number of different "valid" ranges for the alternator output. Here's a sample of them:
- 13.0 to 15.5V,
- 12.5 to 14.5V, and
- 13.6 to 14.4V.

I gather that my alternator output may be just at the limit. Btw, when I touched one of the alternator connectors (I kind of pushed and pulled it a bit), the output voltage dropped to 14.60V and remained steady there.

Before touching the connector, the voltage readings would fluctuate between 14.80 and 14.95V.

Michael

 

[Dan H]

Last time I had an alternator putting out too much voltage the batt. dash light came on. Output was somewhere above 15 volts. Last time I had an alternator not putting out enough amperage, the light would come on intermittantly and all the electrical systems were operating erraticly. Yours sounds like it is probably within the proper voltage range.

 

[HopefulSHO]

It should be hitting about 14v optimally. If you're hitting 12 and 10 you have problems. Voltage regulators are internal - might wanna start shopping for a rebuild again.

 

[cmichaelo]

Thanks all. Alternator seems to behave a little bit "on the edge", but probably still good enough to drive around while shopping for a rebuilt alternator.

And for sure, I'm gonna install a voltmeter gauge to keep an eye on things.

Michael