Idler pulley replacement information needed

If the bolt broke off then you will most likely need to extract the remaining bolt still in the block. Here is the procedure on how to replace the pulley.

Clearly if the idler failed then you will want to install the new one and then make sure the alignment of the belt is correct so that it doesn't damage the new belt.

In order to extract the bolt if it is broken off inside the block then you will need to drill it out. I would suggest getting the replacement bolt and marking the drill bit of the depth of the bolt so you don't go to far.

Let me know if there are questions.