never bothered to use the allen wrench. I just used a ratchet on the tensioner and slid the belt off. When I wanted to put the new belt on it was a little more difficult, especially by myself, but it's doable. I have since removed the belt a second time to install a shorter on to delete my AC pump, and a couple of days later removed that belt and put the other back on. No allen wrench those times either. If you are having problems with the tensioner go to a longer ratchet/breaker bar like otter said, more torque.