I had a brand new motor (the one Inyo recommended) installed on my Pentair Whisperflo pump and it just hums. Sometimes we can get it to start by flipping the switch on the timer multiple times. Electrical and start capacitor have all been checked and are working good. When it’s on it works like a champ. I turbed it off yesterday and tried to turn the impeller through the wet end of the pump and I couldn’t move it . Please help before my pool turns green!