Fan Drive Clutch Test

Fig. 3 Bi-metallic coiled spring removal:

Do not operate the engine until the fan has been first checked for possible cracks and separations.
To check the clutch fan, disconnect the bimetal spring and rotate 90° counterclockwise. This disables the temperature-controlled, free-wheeling feature and the clutch performs like a conventional fan. If this cures the overheating condition, replace the clutch fan.