What was found
(CAN) REDUCTION GEARBOX WAS SENT FOR INVEST. DUE TO METAL CONTAMINATION. DISASSY FOUND- CAUSE OF- METAL CONTAMINATION WAS- #19 BEARING WHICH WAS SEVERELY SPALLED ON- INNER RACE WITH SUBSTANTIAL MATERIAL LOSS. THIS DAMAGE WAS MORE THAN SUFFICIENT TO EXPLAIN- METAL CONTAMINATION OBSERVED.- #15 BEARING WAS REJECTED FOR ELECTRICAL DISCHARGE PITTING BUT HAD SHED NO SERIOUS QUANTITY OF MATERIAL & WAS NOT- SOURCE OF- METAL.-RE IS NO MEASUREABLE RESIDUAL MAGNETISM ON ANY OF- STEEL COMPONENTS, SO LIGHTNING IS NOT BELIEVED TO BE INVOLVED. BASED ON- PRESENCE OF ELECTRICAL DISCH ARGE PITTING ON- #15 BEARING,- #19 BEARING ALSO SUFFERED SOME ELECTRICAL DISCHARGE WHICH RESULTED IN SPALLING & MATERIAL LOSS.