Yes it's me again hunting for free info...... Thanks for your reply in advance!!!
I have installed a new ac compressor, new idler pulley, new serpentine belt the alternator is fairly new ( but could be a suspect ) anyhow, when I try to tork the idler pulley bolt to 40' lbs it squeals really loud so I have to leave it loose in order for it not to make that noise, I have installed a new one with the same results? I am starting to think my fairly new alternator could be the culprit Please help this car is $100 dollaring me to death.

 

"Squealing" could be a loose belt. Make sure you understand how the belt tensioner works. I'm not familiar with your engine but usually, one of the pulleys, either on a component or an idler will pivot through an arc around an axis that causes the belt tension to increase, then you tighten a locking bolt to hold it at that location, then you tighten the bolt it pivots around. Some engines have spring loaded tensioners that you back off by using a breaker bar, slip the belt on, then release to tension the belt. Some tensioners have a screw you turn to pivot the axis and increase the tension, then tighten everything down in place.

Properly tensioned belts don't squeal, loose belts squeal like a stuck pig.

If it's a bad bearing, that would probably be making more of a grinding noise. Those noises are best located using a mechanic's stethoscope (not a real expensive tool).

First see if you can get the belt properly tensioned. If the noise is still there after that, spend a few bucks on a stethoscope to pinpoint it.

 

Not too long back when I thought my bad water pump was a bad tensioner pulley, I bought one and started to put it on...

The one I ended up replacing was the idler pulley (above the alternator) rather than the tensioner, but...

Whichever one you have replaced, you should be able to tighten that pulley down and it should be easy to spin... by-hand-easy. If it isnt make sure you didnt neglect to place the spacer back in behind it (as I did with mine).

Fortunately for me, I realized quickly that the pulleys (all of them) were not bad... no off-axial wobbling, no bumping as it rotated... etc.
But in my case, it WAS the water pump...

Short story? If it cannot spin freely by hand, something's wrong.

 

Already tried the stethescope I couldn't really tell what was making the noise but the alternator didn't sound to happy i must admit, and i did have to change the ac compressor because the clutch assy bearing was wobbling/worn out probably from over tightening otherwise it worked fine before it was changed hmmm hope im not just spinning my wheels? I think im gonna try a new alternator......but first to have mine tested.

 

Thanks leeb already delt with that senario a while back