Central air condensing unit blower needs a push to get it started. After the push start it runs for a short duration maybe an hour or so and then it stops. The circuit breaker trips.
We had serviceman repace the capacitor with a new 5 ufad cap. The problem persists.
Last summer we replaced the fan ,motor and capacitor. The problem still persists.
Any thoughts.

First, What type of system do you have, heat pump or just air conditioning? What is the brand and model number of the unit? Sounds like the fan motor may be faulty, how recent was the capacitor replaced?

The capacitor is 5 ufarad. It was replaced last year.
We have a central airconditioning unit only. It is not a heat pump.
One more observation. After the push start of the blower the air exiting is very warm. This indicates the fan is running under high current. If the capacitor is bad could this happen?
The model is BRYANT. The fan was replaced by a non BRYANT fan. Quite likely not the right model. But the fan worked all of last summer .
I am suspecting that the new capacitor is defective and may have to be replaced with a higher capacitor rating say 7 ufarad.

I think the fan motor is bad. The capacitor has to be the size the motor calls for . If it calls for 5, the use 5. Do not use one of higher rating