I think its best to remove the entire cutter deck for this - it will give you better access to the blade bolts and hub bolts. It sounds like the central bolt has snapped...see if you can undo the 2 outer blade carrying bolts to remove the blade. Once this is off, the hub can be unbolted (4 nuts and the bolts are captive). I reckon its best to renew the complete hub, with bearings, rather than getting the snapped off bolt machined out - unless it unscrews reasonably easily.
To shift the damaged blade bolts - heat them up, then bash on a socket that is slightly smaller than the intended one and try again.
John
May 2009
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