Range rover sport 2008 3 litre v6 diesel coolant problem

only any help if combustion gases are getting into the coolant,if its a one way leak itll get burnt straight out the exhaust,another one is pressure it up with a hot engine,turn it off and leave overnight.ideally you would spin it with injectors out to see any water but if not turn by hand first to eliminate any possibility of a hydraulic lock then start,look for a puff of white smoke.oil system also has a water/air intercooler,a slow leak will evaporate thru the breather system leaving few if any traces.any water connections on turbo+inlet are also possibilities.not all water leaks are head gaskets......