One problem related to radiator hose has been reported for the 2009 Mini Cooper S. The most recently reported issues are listed below.
There is a cooling system failure in my car that has caused cylinder head issues and head gasket issues. Even though my car is a 2009, it only has about 53,000 miles. I purchased the car in December 2019 and in January 2020 the car overheated while driving and then I noticed the coolant was leaking from the car. I replaced the hose and thermostat. Now in August/September 2020 the car overheated again and there was also leaking from the coolant. I took the car to the mechanic and they said the engine needs major repair work. I recently noticed recalls on this make and model regarding the engine and engine cooling, however based on my experience with this car, I'm thinking this may still be an issue with this car. Additionally, I reviewed the carfax report from the previous owners and there was no information about any resolved recalls. However, I spoke with the BMW dealership that the car had work done at from the previous owner and they said the recalls in 2012 (auxiliary coolant pump) and 2015 (heat shield turbo charger) were resolved. I also confirmed this with another Mini cooper dealership. Based on the carfax report, these recalls may have never been resolved.