Outside Fan Problems

Question

The AC fan outside has started to stop working. When i turn it off for 5 minutes or more and turn it back on it sarts back up or sometimes it does not turn but looks like it is trying. I can give it a nudge and the fans comes on. It still stops running after anything from 5 minutes to running fien for several days.
Now it is only runnig for about five minutes and the fan just stops running. Everything else stays on but I turn it off because I know it should not run without the fan running. Is this the capcitor causing this or my fan motor. I'm thinking of putting in a new capcitor. What do you think?!