Just picked up a 48" WB for a pretty good deal. Its a 98-99 model with a 14hp Kawasaki. I used it today and found going up a slight grade/hill, it slows down and eventually stops. I can push it with medium force and make it to the top. I held each side and they seem to pull ok. Im thinking maybe the pulleys/belts might be the problem? I really need some good insight here. This mower will have to last me a few years. Also, there are no extra "spacers" to raise the deck in the front[its on the lowest setting] Is there anything I can use/make with limited tools, instead of buying them at a dealer? Any input is greatly appreciated.