The radiator cap that has not passed the test can’t release the pressure when it reaches the pressure value. The damaged thermostat is unable to carry out a large cycle, resulting in a continuous increase in the radiator pressure. The radiator fan does not turn, resulting in high temperature in the water tank. Drain the air from the cooling system. Refer to the user manual or repair manual. Please refer to owner’s manual to add coolant. Do not open the hood until the steam has subsided. The engine compartment may be very hot, causing serious injuries such as burns. Please stop the vehicle immediately, when “ENGINE OVERHEAT/High Temperature” shows on the dashboard or steam comes out from under the hood. Keep hands and clothing (especially a tie, a scarf) away from the fans and belts. Failure to do so may cause the hands or clothing to be caught, resulting in serious injuries. Do not loosen the radiator cap while the engine and radiator are hot. Serious injuries, such as burns, may result from hot coolant and steam released under pressure. The Core was made from. We have upgraded our package design to avoid this kind of problem. 1968 – 1979 Ford F-100. 1975 – 1979 Ford F-150. 1968 – 1979 Ford F-250. 1968 – 1979 Ford F-350. For 1978 – 1979 Ford Bronco.