tomh2007, it sounds as if the foot valve may be leaking or else there is a crack in the supply line. Either would cause the priming water to leak away when the pump is not in use. Upon start up, you prime the pump manually and establish a water flow. The pump then works well until it is shut down.

This is caused by a foot valve leak not by a crack in the pipe.If there was a crack in the pipe, even after priming the pump it would not work because it would draw air through the crack.
The leaky foot valve could be caused by any particle getting stuck in it so that it could not close fully, or due to age.
The former can be solved by cleaning it and the latter by replacement.
The next time you have to shop for a pump get a self-priming model, it does not need a foot valve. Or even better get one of those open well submersible models.