Condenser fan starts and then shuts down immediately

I am trying to replace my fan motor, and after putting new motor in, I found that it will start to spin. But then stop after 1-2 seconds. I replaced the fan with what I believe is like for like, but it is not working. After looking at the motor, it shows 7.5 mfd, and my capacitor is a 40/5. I am thinking this could be the issue, but the old motor is also 7.5 mfd, and after putting it back in, it is still limping along. The new motor has 4 wires and old has 3. From my research, I was under the impression that just leaving the brown/white wire disconnected (taped up) was correct.. Before buying a new capacitor, I just wanted to see if anyone might be able to help. I believe the issue is the capacitor, or the wiring but not sure which. Any help would be appreciated.

 

Welcome to the forums.

That certainly isn't like for like.

Did the new motor come with instructions for using three wires ?
You will need to change the cap too.