i purchased a simplicity zero turn mower w/ blower last year and have a problem. the belt driving the blower breaks after about 2 hour use. a fix was faxed to dealer last month now i get about 10 hours/ belt. i've been told this blower is new to this unit. the adjustments made was to the belt tensioner. so far about 25 belts are toast. any simular problems or recomended fixes?