It seems I have to top up my coolant level approx every 8-10 weeks so am wondering if there is an obvious leak somewhere or is it impossible to diagnose without getting someone to have a good look under the bonnet. I was thinking could it be the water pump needs changing and maybe cambelt as I'm not sure if this has ever been done. The car has done 62k miles and I have owned it for 9 months. When I top up the coolant with water it is usually below the min level so I just top up back to the max level. Cheers, Dan.