Description Reviews The water pipe is a brand new MINI OEM part with a 2 year, 24K mile warranty from MINI. Fits all gen 2 cars and is the pipe that goes from the thermostat to the water pump on the back side of the engine. The fail point on this part is the o-ring and flange that goes into the water pump. It can crack or break off if the car is over heated or someone gets too aggressive when installing a new thermostat. Don't forget some quality fluid! Or you might even need a new clip.