7. ENGINE REMOVAL/INSTALLATION MXU550EXi/MXU500i Apply lightweight lithium-soap base grease to the front propeller shaft splines and front output splines. Install the front propeller shaft into the engine assembly. Always install the bolts with the new ones. Install the front cooling duct. Make sure the lug on the left crankshaft case into the cutout on the front cooling duct. 7-10