An engine assembly includes an internal combustion engine and a waste heat recovery system. The waste heat recovery system is configured to direct refrigerant around a loop. The loop includes a heat exchanger configured to transfer heat from engine exhaust gases to the refrigerant such that the refrigerant is vaporized; a turbine configured to receive and be driven by the vaporized refrigerant; and a condenser configured to cool and condense the refrigerant for subsequent delivery in liquid form to the heat exchanger. The turbine includes a turbine wheel connected to a shaft which is held in a shaft housing, a bearing lubricated by liquid refrigerant being provided between the shaft and the shaft housing, and squeeze film dampers which utilize the liquid refrigerant are provided between the bearing and the shaft housing.