I have a 'oo disco 2 with 130,000 miles on it and have replaced the head gaskets twice, the last one costing me $2grand. It started with a coolant leak. I would check and see how long the leak has been happening and whether or not it has been driven in that condition. The engine block is aluminum, and my mechanic, informed me that a lot of people will drive the overheating rover, and warp the engine block due to the heat and a replacement is about $4 grand. I am driving mine, but only because I can't afford another car payment right now. When I can.......it is going to be sold. Very cool car, fun to drive and offroad, but no easy on the wallet. IMO, at least have a "rover" mechanic give it a look, so you know what your getting into.