The Delco alternator on my 122S sat for over two years while the car's restoration was in progress. It was stored indoors and did not get crusty. Now the car's running again, and the alternator chirps quite loudly as it spins. I can't tell if it's the belt or something internal -- it's exactly the type of sound I'd imagine a slipping belt might make if it slipped in rhythmic 1/10-second cycles, but it's really hard to say.

The alternator supplies close to 14V to the battery just fine.

Pulley is nice and shiny inside, belt is new, and pulley alignment looks perfect to me.

Adjusting the belt tension doesn't seem to make any difference (I don't like to run them too tight anyway).

Belt dressing has no effect.

Alternator turns freely when spun by hand, no rough spots like a failing bearing or anything like that.

It shuts up when RPM is increasing. It only chirps at steady or decreasing revs.

Probably not related, but I'll mention it: On first start of the day, it doesn't always excite properly -- it has to rev to over 2000 or so for the amp light to go off. After that, it seems to behave. Contacts are clean and connections tight. Everything else electrical works fine, all lights are bright.

Anyone else encounter this? I don't have impact tools to take the pulley off and disassemble the unit... Ron, any input?

Thanks,
--Phil S.