the weather !

Had a new " experience today , opened garage , lock and padlock all reluctant to unlock ,doing weekly check , tyres,oil,water etc etc , took cap off the coolant expansion tank , looked inside to check the level , found it was frozen , I have never come across this before , last night was a real freezer , -7c/-8c , and unusually I had not used the car for 5 days , I fired up the engine and let it idle for 5-10 minutes , checked the tank again - problem gone ,did approx. 20 mile trip , including a bit of M/Way , nothing untoward and running smooth , temperature normal , et al , has anybody else had this happen , I would be interested to hear of any similar occurrences . I am thinking it was probably caused by not using the car in the middle of this " mini ice age " we are having ! Dave.

Hi Neal , thanks for suggestion , coolant mixture should be ok , had new rad fitted earlier this year , by BMW , and have kept to the mix ratio on the side of the BMW antifreeze bottle , this says that a ratio of 1 litre of the blue , to 2 litres of water should be good down to -20c , I certainly hope it doesnt go that low . No problems today when I got the car out , expansion tank ok and nothing else amiss , I just hope it was a one off thanks to the bloody weather , but thanks again , Dave .