This is another thought. Seven pumps in ten years is very unusual. At
least one of those should have lasted many of those years. This makes me
think there's some common problem making them burn out prematurely.
The chief suspect would be the check valve. I've seen this senario many
times. The check valve is faulty, and the water runs back after the pump
shuts off, filling the pit and making for a continuous recycling of the
Maybe you're just unlucky with sump pumps, but do you notice something
that looks suspicious?