My motor worked its way loose, and vibration broke the lower sump. Motor is off the mower, with drive pulley removed and 7 retaining bolts removed. However, it appears there is still one bolt (maybe more?) holding the sump on. This one screws down from the top, so I am not able to see what sort of tool is needed to get it loose. Any help would be most appreciated! (This is off a Toro Timemaster 2014 model in case that makes a difference - 121S02-0130-F1 motor.)