How can an accept/reject criteria be placed on Visual Observation?
Here are some links that may be of help:
Survey of Damage Investigation of Babbitt Industrial Bearings
Non-Destructive Testing on Bearings – Extent and Application Notes
Liquid Penetrant and Magnetic Particle Testing at Level 2
Babbitt Bearings – Manufacture / Refurbish
Engine Bearing Failure Analysis Guide
Journal Bearing Failures