Genuine BMW MINI Water Pump O-Ring - Cooper S
Replacement of the water coolant pump on supercharged Cooper S engines will require one of these. If you are going to reuse your existing o-ring it will be extremely susceptible to leaks. The worst case scenario is you’ll have to do the work again. For the initial financial cost of these o-rings the risk is not worth taking. If you are simply removing the water pump for maintenance to access other engine parts you will require two of these o-rings. For those that are fitting a completely new water pump assembly only one is require; the other is already supplied with the new water pump for the Cooper S application. These o-rings are the second most common area for leaks in the Cooper S coolant system after the thermostat.