Description Reviews MINI Thermostat & Water Pump w/Support #11-51-8-601-366 Fits all Cooper or Cooper S w/ B36, B38 or B46, B48 engines. We see a lot of F-cars with low coolant. We top them up and see how it goes, but some time we have to replace this part because of a seal leak at the thermostat. To find the leak you need to get a small mirror up under the intake manifold and you can see the leak coming from the black plastic and down the block. It never leaks enough to reach the ground, it just dries up and leaves a crusty mess on the block. The only way MINI sells it is as a complete unit. The gaskets are preformed on this unit and are not replaceable. Supersedes: 11-51-8-623-576 (12/02/2013 — 12/07/2015Fits: MINI F56 (04/2013 — 07/2019) MINI F55 (09/2013 — 06/2019) MINI Clubman F54 (11/2014 — 07/2019) MINI Cabrio F57 (11/2014 — 06/2019) MINI Countryman F60 (11/2015 — 06/2019) 2' F45 Active Tourer LCI (09/2017 — 11/2018) 2' F46 Gran Tourer (07/2014 — 03/2018) X1 F48 (11/2014 — 06/2019) X1 F48 LCI ( — ) X2 F39 (10/2016 — 11/2019)