This document discusses techniques for main bearing preventative maintenance and condition monitoring. It recommends manual inspection of bearings every two years if using manual re-lubrication, and inspection before installing automatic lubrication systems. Condition monitoring faces challenges due to slow shaft speeds and variable operating conditions, but vibration analysis can detect bearing defects, especially when measuring acceleration spectra. Connecting condition monitoring systems to automatic lubrication can provide lubrication on demand when bearing issues are detected.