Hellnback

Bros!! How "tight" is the Alty shaft supposed to be? putting it in right perspective. IE: the tensioner really rotates freely similar to the fans. how about the alternator,my XJ 2000 Alty is quite tight compared to the other shaft mentioned. when trying to spin it with your hand, how many revolutions should it make? reason is, I am analyzing where the slippage is occuring? I have a squeaking noise when starting then disappears in few seconds.
Thanks for the input!!