The 40-hp drive motor for a critical line stopped running and won’t restart. One of the operators said, “It made a heck of a racket and then everything stopped.” After pulling the motor, you confirmed that it spun a bearing.
Fortunately, your stockroom has a direct replacement sitting on a shelf. Production sends a lift truck operator to go fetch it. You work heroically fast, and before long you are ready to remove your lock and tag from the disconnect.
Grinning broadly, you close the disconnect and ask the operator to restart the line. Success! While you’re being congratulated, there’s suddenly a heck of a racket and an operator says, “That’s what it did before! Did you put the old one back in?”
You double check, out of disbelief. No, it’s the new motor.
The problem is that new motor sat for a long time in the stockroom. By the time the lift truck operator retrieved it, the motor was badly in need of a grease change. The short-term fix is yet another replacement. Be sure to put the new motor on an ultrasonic bearing inspection PM.