So I searched and couldn't really find an answer. I just bought a new Idler Pulley and I was wondering if I'm just supposed to bolt it in or if I have to grease it first. I know it's probably a dumb question. Any input is appreciated. Thanks

 

It's a sealed bearing . No way to grease it unless you use a special needle adapter.And if you have to do that it needs replacing again.
Just bolt on the new unit.

 

Ok, thanks.