Broken teeth on the drive coupling

Since the coupling is threaded, it can be easily screwed on and off if you immobilize the shaft. If you don't have a tool that can do this (the space between the drive coupling and the body of the blender is only about 1/8"), you can insert a long bladed screwdriver into the vents on the bottom of the blender and into the motor. When you turn the coupling, the motor won't rotate and you can easily screw off the coupling (the threads are reversed, so turn the opposite way). Good luck!
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