As luck would have it changing a bulb on my wifes car I see pink coolant on the engine just below the thermostat housing. Bit of googling and it seems a common place to leak, the housing is metal but they screw a plastic fitting into it that goes to the heater. Guess where it failed … Moment I took a spanner to it snapped in two. Was a lucky escape. Uno’s for Africa sells a brass insert for R200. Why on earth would one skimp on not making it 100% metal piece. Sometimes I swear newer cars are made with a expiry date !