I have owned my 97 XK8 for 13 years now and it is still my favorite car to drive. It has always been stored in the winter and it just turned over 170,000 Km.
I have just encountered a new problem with the engine coolant. The coolant low warning came on and it required 2 small cups of water to top up the tank. I drove it about 200 Km and he coolant low message came back on. After the car had been parked for about 30 min., I checked under the car and saw coolant discharge under the engine area where the overflow tube is. I waited overnight and checked the reservoir tank and it is now empty. It has been around 90 F here and I would expect maximum expansion of the coolant, but not to the extent observed. I can top up the tank with coolant again, but I do not think this will resolve my problem. I am not sure what would cause the coolant system to discharge that amount of fluid, and then when it cools to suck the tank dry. The engine temp gauge indicted normal operating temperature during the entire trip. Any suggestions?

Thank you