Alternator belt screeching

[ukstu]

Hi all,
Some advice if possible from your knowledgable selves.
I have a 5.7 Alpha one. I’m getting the screeching noise from the alternator belt, one chewed up last year and threw itself off.
ive tried adjusting and re-aligning but can’t seem to stop the noise ( and the fact that it is clearly destroying itself).
by eye it looks correct but something is not and I can’t figure it out. I’ve checked the mounting brackets, all bolts are correctly fitted and tight. Any advice would great..
( pretty sure it has had correct belts, parts ordered for correct engine)
Thanks in advance..

 

[Alumarine]

Have you put a straight edge on the face of the alternator pulley to make sure it is lined up with the other pulleys?

 

[ukstu]

I have yes, used a metal rule. However I didn’t check all three pulleys, will recheck all of them and that they all align, tht said, it could only be the alternator tht wouldn’t be straight wouldn’t it?

 

[Bt Doctur]

Belt worn, too loose, too narrow

 

[Alumarine]

I have yes, used a metal rule. However I didn’t check all three pulleys, will recheck all of them and that they all align, tht said, it could only be the alternator tht wouldn’t be straight wouldn’t it?

This is what I meant by alignment.

 

[GA_Boater]

Loosen the belts and spin everything with a pulley except the crank pulley. Check for dragging and notchy bearings.

 

[Bondo]

Ayuh,..... Those rusty pulleys needs to be sanded, 'n painted, or it'll continue to chew the sides of the belt,......

 

[ukstu]

Ayuh,..... Those rusty pulleys needs to be sanded, 'n painted, or it'll continue to chew the sides of the belt,......

All removed and done today!