If the motor Is bolted on a bronze flanged tube that is bolted to the end of the last gurdie stancion their shouldn't be anything other than a woodruf key on the motor shaft stuffed inside a bronze sleeve or coupling......sometimes they stick...work on it ...It'll come loose. If you can get a small separation between the motor face & the bronze sleeve...a couple wide flat bladed screwdrivers or thin wedges will get It to back off...just careful prying against the soft bronze. Hope that helps.. Andrew