bolt size

[sawwood]

 I needed a new blade roller on our mark 4 Norwood and i had  a spare one. When i went
 to install it i notice the bolt that holds it is smaller then the inside of the bearing. I looked
 in the parts listing and the bolt is a 5/8 size. I took the bearing to tractor supply and a 5/8
 bolt is also loose in the bearing. I looked at a 16mm and it was loose and a 18mm was to
 big. On your guys roller is the bolt that holds it small to or does it fit the size of the beaning?

 Sawwood