how do you know if the motor coupler is bad?

I am trying to diagnose a noisy (knocking) while draining/spinning problem. The machine is not out of balance though.We have the motor coupling off the machine. How do you know if it’s bad though?:confused:

if the motor coupling is bad it will be torn to pieces or the center part where the motor shaft slides into will be stripped out (round instead of stop sign shape)

Attach the coupler to the tranny and turn it clockwise till the tranny starts spinning the clutch housing. If you feal any gaps or rough areas, you have a busted gear in the tranny.
If ok, and the washer shakes while spinning, check your three suspension springs.