My 1970 XJ6 has developed a heating problem. For some time now the heat gauge rose up to 75% when the car is driven, but now when I switch off the motor a lot water steams out of the reservoir. There is no radiator cap, this area appears to be sealed by the previous owner. The reservoir has just a plastic cap (no pressure release). The car is mostly driven for 30 minutes weekly and now when it is used for 60 minutes or so, there seems to be a problem. Any advice on on checking the water pump or oil dip-stick for certain signs and the radiator?
Thanx in advance! Vassie