1995 LS400 idler pulley problem

[simpson3]

I just got done replacing my fan bracket mount and I went to reinstall the top idler pulley. When you spin the pulley it tightens the bolt, which eventually it locks up and will no longer spin. Am I doing something wrong or is the pulley bad.

[TrevC]

sounds like you are missing a spacer behind the pulley which should keep it off the bracket.  Look down the belt run to see if it aligns or if it is offset, this should confirm