What is the average lifespan of a 6055? In the last year I have had the shaft come loose from the motorblock on 3 separate pumps, the most recent this past weekend. In that same time the power supplies for 2 of thoes three pumps have stopped working randomly. I have cleaned the pumps regularly and the power supplies were never mistreated. I purchased 2 of the pumps used but in good condition about 2 1/2 years ago and the other about a year later. The entire time they have been run on the single controller or 7096 multicontroller. Is this normal wear and tear on these pumps or am I just really unlucky? Thanks.