Bluespud...
The load is not the problem for that motor. It's the time and lack of cooling!
Typically, that motor has no fan on it to cool it so you will need to force air over it constantly!
Also, it is probably a permanent split capacitor motor with a capacitor that WILL explode if you run it for 15 minutes!
I think you would do best to purchase a standard Continuous Duty Capacitor Start motor for your application, since the motor you have was never designed to do the job you describe!