The normal test is spin and release cold, feels like peanut butter inside, repeat when warmed up and engine stopped. If it coasts to a stop more than 1 revolution, the clutch fluid has left the building with Elvis. Freewheeling means it will spin (to the eye) but with such reduced torque that air flow is low. Mine had the AC fans wired reverse polarity, when they turned on the main fan would be sucked to a stop, so overheating at idle was quick.