I have a 1hp about ground well pump. When the pump goes to switch on, it hangs up, you can give the fan propeller a tap and it will start.

I think I understand your question. I believe you mean you are tapping the impeller housing to make it start up. Correct?

I would remove the impeller housing and check to be sure there is no trash or other material which is hanging up the impeller. If that is not the case, then perhaps a bearing is starting to go.

Is the switch attached directly to the pump, or on a separate line?