I got x type diesel that has been loosing coolant for a couple of weeks but not able to find leak,now I think it's the head gasket,any ideas on how much this will cost, or is it better to fix myself,I got the car this year and love it,fitted new turbo last week and new thermostat housing as it started to leak,so not in a hurry to give up on it,any help would be good,cheers mike.