Yes, forget the 3 wire pump. I dont know why some pump guys continue to use them. If its less than 2hp then always get a 2 wire pump. Its common to find a pump that has "spun" or disconnected itself. Especially something like what you have, a 1hp pump. Its a pretty big animal and it when it initially kicks on, you get some thrust down there.
Check to see if the pump will run. If you have an amp meter, wire nut the pump directly to the wires going out to the well and have somebody throw the power on for just 10 seconds or so. See what the amp draw is and see if that matches up to a 1hp pump (usually just under 10amps, but will spike up 20+ when starting). Chances are the pump is good.
If you do decide to buy a new pump and get a 2 wire, then you will have to hotwire the control box inside. A lot of the time people will run 3 wire pumps without the ground leg because 90% of the time its 2 wire pumps and most guys don't have an extra spool of wire with 4 leads on it along with one with 3 leads.
Best of luck to you! BTW - Get yourself some stainless steel adapters for when you attach the pump back on the poly pipe. And use 2 hose clamps. Heat the poly, slide it on the 1" stainless adapter and try and clamp down as tightly as possible while its still warm. Get yourself a few torque stops on there too if there arn't any already.
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NJ Well Pump Service & Repair