Truck is 1993 C2500 7.4L (454) engine

I recently had the alternator seize up (actually had a little flame inside). So, I replaced the alternator and I replaced the serp. belt.
Now, within 500 miles, the alternator bearing is giving out. The shop that supplied the alternator says that the problem is the tensioner is too tight which puts too much strain on the alternator pulley (?)

Does this make sense to you guys? The tensioner is a spring-loaded device...as it wears, it would seem that it would loosen, not tighten.

Another suggestion but a knowledgeable friend was that the belt they gave me may have been too small?


Any advise would be appreciated - I plan on putting on another new alternator tomorrow night and don't want the same thing to happen.


Thanks

Remove the belt and see if the tensioner moves freely from the max postion to the minumum, if so the alt is bad, if it binds sticks or locks in any position as you move it thru it's arc, it is bad.

Remove the belt and see if the tensioner moves freely from the max postion to the minumum, if so the alt is bad, if it binds sticks or locks in any position as you move it thru it's arc, it is bad.


Well, I can't move it by hand, but it does move freely when tools are placed on it. I also suspect the alternator is the culprit - I'll keep an eye out for other posts! Thanks!

PS: The pulley itself does rotate smoothly.

You mean the tensioner pulley? if so it should.

You mean the tensioner pulley? if so it should.

Yes, I just wanted to be clear when I said that it moved smoothly. The pulley rotates smoothly and the tensioner moves smoothly :)

I just exchanged the alternator and I noticed right away that this alternator does turn smooth, but if you spin it, it stops itself after a turn or two. The prior one that went bad would practically freewheel. I think maybe they didn't tighten something up when they made that alternator ;)