Under Hood Crying?

2000 Blazer LT63k While the engine is running I have a quiet WHINING. It's not that loud and it does not get any louder with rpm change. It's not the belt either. From the sounds of it, it almost sounds like a bad bearing in the alternator or A/C motor. I can't pin point it out either. I've checked for vaccum leaks also and none located. Any help would be appriciated.

Take the belt off and start it up for a few seconds. If the sound is still there it's not a bearing on the acc. drives. If gone try turning each pulley by hand and listen and feel for a bad bearing. Not uncommon for an idler or alternator bearing to go out.

If it is the alternator or the A/C or power steering, it will change with rpms.

.......And so will the idler pulley and the tensioner pulley

More than likely, a whining sound is usually from the alternator on a 4.3L.

It was on mine.

mine did the same i replaced the belt and idle pulley but that didn't help
I had to change the water pump a few months later and what do you know the thing quit whinning
Good Luck