My engine is whining like a supercharger

[Treltom]

This is a 74 Super Beetle. We recently put in a new clutch, new flywheel and a chrome crankshaft pulley. After about a week, there was a faint scraping sound that only happened when the clutch was released. We also noticed the generator light wasn't working, but don't believe those things are related.
Fearing that something came loose in the new clutch and flywheel installation and deciding to install a new alternator, we pulled the motor again. With the motor out we discovered the scraping sound appeared to come from the new crankshaft pulley rubbing on a piece of engine tin. We fixed that, installed the alternator, replaced the engine and now the motor emits a whining sound, sort of like what I associate with a supercharger. I believe it is coming from the new alternator. Does anyone know if the alternator is a likely theory? Is this anything to be concerned about?
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74 Super Beetle - runs but needs TLC
74 Super Beetle - project with huge potential

[VW_Jimbo]

Yes. Alternators can emit a noise when under extreme load or a bearing is going out. But a better option may be the cooling fan is rubbing the fan shroud internally or rubbing on the backing plate.

Take the belt off. Start the engine and listen. Turn the engine off. You can only run the car less than a minute or so or engine damage will occur. Did the noise go away or remain?
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Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!