Hello, Volut cracked overnight and leaked for several hours, drainig the pool down well over 1 foot. Next day, replaced volute, but now polaris is not functioning. Water is being pumped into the polaris, but it does not at near enough volume. I pulled the hose out of th polaris and seems like water pressure should be much higher. The wheels will not even spin on the polaris, but i believe the polaris is fine. My guess is the motor is weakened (not rotating at full rpm's), or a part was damaged while running with no water flowing through it when it ran throughout the night. Any ideas. I appreciate any assistance.

With a new volute the most likely causes for low pump flow is a restricted return line, a restricted suction line(or air leak), or there is something wrong with the impeller in that order. There is a filter screen in the return line that can cause the return line to be restricted if it is plugged. It is either in the wall fitting or in the tubing system close to the wall fitting. If it is dirty it means that debris is getting into the system. Typically an early indication that a grid in a DE filter has a leak in it is a plugged cleaner filter screen. The speed of the motor could be causing the problem but this is rare without causing an over current condition in the motor causing it to shut off. My suggestion is first check the return filter screen. If it is dirty then clean it out. Before connecting the return hose start the pump and check the flow by reaching down and manually putting your hand over the water stream coming out of the wall fitting. Turn off the pump and connect the cleaner hose without the filter screen installed. Disconnect the hose from the cleaner and hold the end of the hose while someone turns on the pump. Water should come out of the hose at a high rate. Next install the filter screen and the flow coming out of the hose should be about the same. Now try connecting it to the cleaner. I hope this helps.