Drive Belt Idler pulley bearing

[goforit]

Hi,
I have a sound like a bird chirping under the hood of my '94 318i. I believe it to be my drive belt idler pulley. (not Vee-belt) Can the bearing be replaced in this pulley or do I have to order a new pulley? Is this common?

Thanks!

 

[Kirby]

You must replace the assembly. It is a sealed bearing and connot be repaired.