I bought myself a discovery 300tdi the other day and of course filled all the essentials up such as oil,rad water etc. After pootling round near the house i then took it out onto the dual carriageway and opened it up abit more to watch my thermostat rise and white smoke come flowing out the exhaust!when i got her home checked oil and everything was fine no signs of water or loss of it. I then checked my radiator tank to discover it empty!filled it up again and same thing happend!Was wondering if it could be a head gasket as they are known for going?