The V-belt is turning over in the motor pulley. The Primary Mower V-belt is not sitting the right way in the V on the motor pulley which is chewing the belt up.The belt is OK in the other pulleys. If I have the tension to tight the motor will not start because it turns the blades on the mower when the mower is still not engaged. I would like to know what I have to do to fix this problem because the new belts are not lasting very long!!