Take the drive unit out, and give it a thorough cleaning, soaking alone will not get the lime deposits out of tight spaces. Long term, if a push start is required the pump can be damaged as it is using more power to run. The reason it needed a push start was the resistance was too much for the electromagnet to overcome on start up, usually in these cases the pump is running at near the maximum wattage it can handle. The problem usually is due to calcium build up on the upper bearing, often it is stuck to the magnet.