To share with users of Turbo machinery/ Pumps, a very typical and practical learning about repeated problems of high vibrations in newly commissioned electrical motors of two different pumps in Crude distillation unit and Bitumen unit of Refinery. The vibration spectrum indicated the domination of bearing fault frequencies. Motor bearings (antifriction bearings) were found defective and hence replaced, but the phenomena got repeated just after 2 months of replacement with similar defect frequencies as before. After analysis of failed bearing it was revealed that the root cause behind high vibration was generation of shaft voltage - leading to stray (leakage) current, which is unusual for HT motors of these frame sizes.