I had a belt break on my Scag Z cat today. It had 90 Hrs on it when it broke. I scalped a yard with it last week and I'm sure that was placing a load on everything. Is this just a premature breakage or does scalping an 8500 sq ft lot really stress out the blade belt? I always maintain my equipment, spindle greased every 8-10 hours, blades sharpened every 6-8 hours. Any input?