I have a 1.5hp Sta Rite pump. The other day it stopped running and only hums then trips the motor after a few seconds. The shaft turns freely, and I have checked the impeller for blockage. When I turn the power on and spin the shaft the motor runs fine, so I am assuming it is the capacitor. Mine is mounted on top. ( Start Cap?) This is all fine except the motor runs for about 5-10 minutes and shuts down. My question is could the assumed bad capacitor cause this and if not any suggestions. There is no noise within the motor and it seems to running smoothly bofore it trips. Thanks in advance...Charlie