Bottom roller replacement:
Remove the 5/16-18 x 1 3/4 Hex Head Bolt (HHB) , lock washer , flat washer , and roller .
Apply medium-strength thread-lock compound (for example, blue Loctite®) to HHB. Replace the roller  and eccentric bushing . Install the components in the opposite sequence they were removed. Make sure the roller  is tight against the V-rail .
Rotate the eccentric bushing  until the roller is tight on the rail.
Torque the HHB  to 20 ft-lb (27 N-m). Apply Mobil 460 grease to the bottom V-rail .