How many hp is the Bomb, previously it did not turn off? That is, it was not intermittent, is she sucking from a well of how many meters ?; if it did not do this, it is surely that it overheats because it is sucking air that is, it loses the fat, if it is a well I recommend you put a checker at the end of the tube and if it has it I recommend you check, what is triggered is the thermal heating, performs general maintenance to the rollers and fan must have a lid, many people take it off and they stop cooling the winding, you must stick the starter and work coil.
Megar the coils makes them with respect to earth, if it is starting with the same force and you do not have to help it by the fan to start it I do not think it is the problem, but do not go to place a larger one because you can burn the pump , I hope it has helped you solve your problem we are at your service.