Got strainer pump lid off with the mallet. Thanks!

Still cannot get prime running pump off main drain - I have 3 gate valves (main drain, pool skimmer, and spa skimmer) When I open the Ball Valve to the gate valves the pump loses prime immediately.

My pool guy says I have a leak somewhere and that he did not see any anti freeze from the pool close.

Any ideas where to go from here. ????