Installation Failures: Some mechanical seal failures come from wrong mounting and handling. Examples can be shaft misalignment, seats not mounted perpendicular to the shaft, axially moving shaft and wrong assembly length, etc.

The position and width of wear tracks on the seat indicate various problem areas. If the width of a wear track on the seat is the mirror of the sliding face of the opposite seal ring, the shaft seal seems to be well aligned with no run-out of the shaft.