Description Reviews MINI Cooper S Turbo Coolant Return Lines run from the turbo to the bottom of the thermostat as well as the expansion tank for all N18 motors. When doing an oil service on your Cooper S N18 motor, you need to slide the tank out of the way to get to oil filter. MINI made this hose really short and tight and as you move the tank out of the way it can snap the plastic fitting as shown in the photos. The plastic fitting over years of heat just becomes brittle. This is a quality MINI part and comes with all new clamps. Fits the N18 Cooper S engine and is the newest, up to date part.