Alternator noise

Sometimes I turn my Headlights on in daytime to keep left turning idiots from
"not seeing me".

Recently I left my headlights on when I parked for about half an hour while
visiting an establishment for a quickie....a hamburger, guys!

When I started the engine, I heard a noise which I at first thought was my
water pump going bad - like a bad bearing sound.

Then I realized that the Headlights were still on and figured out that the alternator
was charging a low battery with the lights on also.

The Belt was not squealing as it usually does in that case.

Is this normal or is my alternator going south?

After a few minutes the noise (not a grinding sound) went away and I have not
heard it again.

Strange....

I made a relay - buzzer device for warning when leaving the lights on (daylight situation),
but haven't installed it yet - bad winter weather keeps me from working on the Metro.

DoctorBill

I have heard of this before. Your Alernator was under much more of a load than it was designed for. I would not be too worried about it. However, if it would make you feel better, your auto parts store can test it while it is on the vehicle. If you want to travel that far just for that.

Weak or almost dead battery barely enough power to start the car and it's now noisy?
I would load test that battery!

The Battery is only one year old and started the car well.

I had just left the lights on for a while.

The alternator is still the one that was on the car when I bought it used many
years ago...getting long in the tooth.

I'd probably be smart to replace it just for the grins of it and be safe.

Will probably fail 100 miles from home on the road between here and Hell on a windy,
rainy night in a town named "The Living Dead" on a Sunday at 3 AM while I am
having the "Tijuana Two Step."

Did I leave anything out?

DoctorBill

If it's all OK now, then you know what the problem was by reading your original post.

My caprice had a parasitic draw (stereo) that would drain the battery after 24 hours. So I'd have to jump start the car a lot, and leave the task of charging up the battery to the alternator. It made some noise because, as 94 pointed out, alternators are not designed to charge dead batteries, nor do they appreciate it very much and eventually this will kill an alternator. But the alternator in the caprice is fine, and if I were you, I wouldn't be concerned.

-MechanicMatt