For a qualitative test, put the meter in the 20 meg position. Expect the display to show non-infinite briefly when you connect the probes to the isolated terminals. Then back to infinity. Reverse the leads, and get a slightly less brief non-infinity.
But to measure the capacitance, you need one with a capacitance setting.
Most caps for motors are electrolyte, a liquid inside the cap. When they go bad generally they swell near the blade connectors are or they leak oil. Some have a blow out valve. I never had a cap tester, I always used a meter like yours.