I need help w/ my bobcat ransomes 36 w/b mower. 12.5 kawasaki. The motor has developed a knock after sunk carb float filled the oil w/ gasoline. I have a briggs 12 horse to replace it with, but I cannot figure out how to remove the pulleys on the engine shaft. Is there any special way to remove them? I removed the spring and tried using a puller on the variable speed pulley and managed to crack the pulley w/o even budging it. Any help would be greatly appreciated. I believe the briggs motor I have has a 1" or 1.25" shaft, does anyone know if there is a way to make the bobcat pulleys fit, or know of a place I can get pulleys for the Briggs?