Before I started all this work I searched this forum for specifics as to which bearing I need, how its done, etc, but I could not get a straight answer. So here is how I replaced the bearing in my tensioner pulley

Stock bearing part no. NSK 6204DU

This is the pulley I am concerned with (old picture)



Pulley Removed






Old bearing on the left, new on the right



Closeup of the old stock bearing



New bearing installed

 

Did you need a hydralic press? I was able to press mine in using a large bench vise and a piece of pipe that was the diameter of the outer bearing surface.

 

I used a socket and a hammer to remove the bearing.

I tossed the new bearing in the freezer for about 20 minutes, then I applied heat to the pulley with a small propane torch. I fetched the bearing from the freezer and it dropped all the way into the pulley with zero effort.