I would take the motor back and have them give you new one. Most likely it is a defective motor. Now, the motor may have failed from your attemps at wiring it in a trial and error sort of way, but they don't need to know that, just tell them what the motor is doing and ask for a new one. When you get the new motor, I would suggest hiring a different ac company, or even an electrician and have then wire the motor. You can install the new motor to save some time and money, but having the motor wired properly is very, very important here ok?. A separate capacitor would be the best way to go, since that's what the wiring diagram calls for, but you can use a dual cap as long as its wired correctly. On a dual cap, one spade if for the compressor, one is for the fan, and the other is a common, or power into the cap. Now I would try to expalin exactly how to wire this up for you, but I'm not here to write a chapter in a do it yourself ac book,ha. Anywho, like I said, get the return the motor for a new one, install motor to save time and money on the service call, then have a pro come in and wire it up for you. Should be a quick and easy job for a pro. If you have a chance to be around when the pro is wiring the new motor and capacitor, watch closely and ask questions if you wish. Just remember, the longer you and the pro conversate, the higher the bill will be because, well, quite simply, time is money. Good luck and please let me know how things work out..