Our pool is about 7 years old. We left for week vacation and kids left the pump on 24/7 for about 10 days. When we got home the pump wasn't running. The breaker had tripped so reset it and turned on the pump. Humming, no movement and it got really hot. Thought there might be a blockage in the plumbing so blew water through the system from the pump side and also back through the strainer side and it was fine. Read posts on possible solutions and tried them ...Impeller turns fine, hit motor with a hammer, etc. and nothing worked. Removed the motor and saw there was a crack in the diffuser. tried to remove the impeller to check the spring and seal assembly and the ceramic seal but could not get it apart. In the meantime, checked our other pump which runs the water features only and it did the same thing, no motion, hums and gets really hot. Again the impeller turns fine, checked the diffuser and it looked fine. What are the chances of both motors going out at the same time? Anyway, was going to get a new diffuser and a start capacitor for the fist pump but since the pump is 7 years was thinking of replacing with a 2 speed pump. Any input would be appreciated.