Guidance for upgrading the HydraFiber Processing Unit upper shredder from AA75 belts to BB77 belts focuses on correct removal, installation, and adjustment steps. The procedure covers removing existing AA75 belts, repositioning shaft collars and thrust components, and eliminating the flat idler pulley from use. A new double-groove pulley is installed and aligned with the shredder pulley face, with thrust bearing components reinstalled in their original orientation for optimal grease retention. The bulletin also specifies greasing the bearing while spinning the pulley and setting final BB77 belt tension to 3/8″ deflection at 4.5 lbs. pressure.
Key Points
- Replaces AA75 belts with BB77 belts on the upper shredder of the HydraFiber Processing Unit.
- Directs removal of the flat idler pulley and re-positioning of shaft collars and thrust components on the tensioner assembly.
- Specifies installing and aligning a new double-groove pulley and properly reinstalling thrust bearing components.
- Calls for greasing the bearing while spinning the pulley and adjusting belt tension to 3/8″ deflection at 4.5 lbs. pressure.
