Product review (5 stars): No More Noisy Dishwasher
The seal that goes around the shaft on these diverter valves fail and then the water destroys a switch that is in this valve.  You will need to buy the shaft seal separately either as a new old stock part if you can find it or as part of the entire sump assembly.  The valve itself is easy to install.  I have had it in for a couple months now and everything is working fine.