Whirring sound from accessories side of engine

[series8217]

1993 3.4 TDC in a Fiero. Sounds like a loud belt or a bearing whirring. From inside the car its loud enough that it sounds like I have a turbo when the engine revs. It is also audible at idle. Its a very smooth sort of whirring, no squeaks or chirps.
I have a new water pump (200 miles) and all new timing belt, tensioner, and idler pulleys.
Is it possible that the timing belt is making this noise? Why would that happen with all new parts? I'm going to inspect the belt after the engine cools off to see if there is any weird wear. If I do see some belt fibers around, should I be concerned or is it normal for there to be some initial wear on the belt? Only 200 miles on it all right now.
The alternator, A/C compressor, and accessory belt tensioner have not been replaced. I do not have a power steering pump as this is in a Fiero so I have an idler pulley in its place; it has an old bearing in it but I have to have machine work done to it to put a new bearing in because nobody sells on that fits.. so I can't check that until at least the end of the week. I picked up another pulley from the junkyard today so I could drive the car while the other pulley is at the machine shop, but this one has a bad bearing too (it wobbles a tiny bit, though not nearly as much as the other one). The noise is the same though, if not louder.
The engine runs too rough with the accessory belt off to be able to tell if the noise is gone or not with the accessories not spinning.
Anyone else experience this?

[series8217]

Took off the timing belt inspection covers. Timing belt width appears to be fine. However, the top surface looks like it might have been running up against something? I can't tell for sure as I don't remember how it looked before.

I can move the belt a bit if I push it where it is in contact with the cam cog. Its hard but it'll move. Is that normal or should there be more tension on it? I would think my timing would be weird enough to make a noticeable diff and that it would be slopping side to side and get chewed up pretty quick if there wasn't enough tension on it.. but maybe not?
Can I apply more tension to it by wrenching the tensioner pulley without having to reset the timing (would have to drop the engine if I had to redo timing due to not enough clearance to take off the cam cogs.. stupid lock rings).

[series8217]

Just finished a thorough inspection of the timing belt system. All seems to be okay. The tensioner is still holding tension, bracket is in one piece and not cracked, there is in fact plenty of tension on the belt, and everything looks pretty . I'm not concerned about the light wear that is visible. Could be the belt was slightly thicker than it should have been and was wearing against the front cover down by the drive sprocket where there isn't much clearance.

That leaves me with bad reman water pump, alt bearing, idler pulley, or AC compressor. Sadly, I don't have the compressor hooked up so I can't engage the clutch to see if the tone changes..

[Lowerd1]

Easiest way to find out is remove the Serpentine belt and start the car. Don't let it run but for a few sec and see if it makes the noise. If it doesn't make it then you know its an accessory. Now with the belt off spin each one by hand and listen to it. If one it hard to turn or makes some odd sounds its probably that one.

Another thing to think about is it may just be the belt. My car makes that same sound and every accessory is brand new. It does not make it with the sepentine belt off, but does with it on. I chalk it up to my gatorback belt I guess. Everything works great just a loud whiring sound.

[smilinguy99]

When a water pump bearing is going bad it can make a whirring sound.

[Kohburn]

mine started doing the same thing after i topped off the cooling system - I fear the water pump --

I'll try the belt trick to check

[series8217]

I finally figured out what it was. With the engine at rest my power steering delete idler pulley interfered with nothing, but the bearing has some slop in it so when the engine is started it begins to wobble and rubs against the timing belt inspection cover. Eventually it made a groove large enough that it no longer interefered and it is now silent.
Besides that, I do still get a quieter whirring from the alternator bearing. I put another alternator on temporarily and it was a similar sound but even louder. Damn alternators.
Engine is out right now for investigation into metal bits and probable rod knock.