Hoover failed miserably when developing this device. They used a flimsy strap and buried it inside the device, making it very difficult to swap out. You must remove the entire chassis by removing the 14 screws and then carefully prying up the left side of the chassis to expose the drive gears. The drive gear assembly will tilt up, then you will need to gently lift the small tab on the center portion of the tensioner as you slide it down. Then wrap the belt around the two end sprockets and over the tensioner, then slide the tensioner back up until it clicks, tensioning the belt. You need to do this last step because you can't just wrap the belt around the sprockets and tensioner without first sliding the tensioner down (the belt will look too long then). In the picture, the tensioner is a small white gear with no teeth.
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