I have a Snapper LT140H38ABV 38" 14 HP Hydro Drive Tractor Series A with B&S 14hp motor Model# 287707-0228-01. I want to replaced the engine crankcase gasket as it has a serious leak. How do I remove the dual belt pulley from crankshaft ? I've removed the bolt from the end of the shaft but it seem to be frozen on. Is the a special puller needed ? Any suggestion would appreciated