Excello Grinding Spindle Refurbish
Possible cause of failure:
Front bearings contaminated with grinding dust, more so in the #1 bearing.
Wheel hub & hub retention nut show heavy wear from use (hub also loads the front bearings.)
Front housing labyrinth nut worn from grinding dust.
Rear bearing journals are undersized -24/-40µ (ISO is 0/-7µ) and appear to have been previously flash chromed.
Clean, inspect overall dimensions.
Manufacture a front housing labyrinth nut
Grind, plate & regrind rear bearing journals.
Replace bearings and felt seal.
Adjust preload, balance, assemble and break in. Final quality control inspection.