i have a land rover disc dti which overheated and the cylinder head gasket got bad,it was replaced. I moved about 200kilometers from the place it was replaced to my house.The next day,i moved about 15 kilometers when it started overheating again.Plesae what could be the cause of the overheating?
Probably the cylinder head is warped, I know you have had a new head gasket but if the cylinder head got warped when your car overheated then it needs to be either replaced or skimmed ( ground ) flat again other wise it is a waste of time and money replacing the head gasket.
Apart from what has been said, Possible air lock within the cooling system, put on your heater & turn to hot, does it blow hot >>cold>>hot>>cold if so, the system wants bleeding.
Where to start? Faulty thermostat, Faulty fan motor, Faulty fan motor thermostat, lack of water, clogged header tank hose, delaminated coolant hose, water pump not functioning (does it run off the fan belt or the cam belt?) radiator clogged.
Diesel cyl heads do crack over time. They are minute cracks that cannot be seen by eye but often generate pressure in the cooling sytem. I know this from experience, but in a VW. The garage told me that the tremendous battering a diesel gives the head does break down cyl heads. In some lorries the heads are replaced but the rest of the engine just carries on.
But in your case check that other probelms are not causing it, blocked radiator( you have not put dreadful radweld in have you!) , thermostat sticking, leaking hoses and a warped head as spmeone said. You have to check that when taken off and a straightrule set against it.