Dismantling and checking the thermostat — only when the engine is cold

An experienced motorist is quite capable of doing such a job. When you are ready to start it, you can first remove the working pressure in the cooling system and prepare the necessary spare parts. You will need a thermostat (for Duretec engines completely with housing), a cover gasket for the thermostat housing, as well as an elastic and heat-resistant sealing agent. If necessary, collect the drain coolant in a clean container, it can be reused after the repair.

However, if you want to check the functioning of the old thermostat, heat water in a special saucepan and check the temperature of the water with a home thermometer. Read the control temperature on the thermostat housing and compare it with the actual water temperature. We naturally do not advise you to rely entirely on «untidy» thermostat. Electrically heated Mondeo thermostats can also be tested with a multimeter: measure the resistance between the two pins - a well-functioning regulator has a resistance of 15 ohms.

PROCEDURE

Open expansion tank to release system pressure. Be careful when the engine is hot: risk of scalding. That's why «pack» cover in a thick woolen rag. Place a clean collecting container under the radiator and disconnect the lower radiator hose or remove the reservoir drain screw. Drain approximately three liters of coolant. Double packed: in Duratec engines, the thermostat consists of a housing and a regulator. 1 - Thermostat / housing block, 2 - Electrical plug connector, 3 - Thermostat valve spring, 4 - Valve, 5 — «valve spring short circuit», 6 - Regulating element. Loosen the hose clamp on the thermostat housing and disconnect the hose. Unscrew the three fixing screws of the thermostat housing and remove the housing. If it is tight, help it free with light hammer blows (rubber or plastic). Thoroughly clean all sealing surfaces and screw the new housing onto the engine block. Lubricate the new gasket a little beforehand on both sides with an elastic and heat-resistant sealing agent. Reconnect the hose and secure with a hose clamp. Pour in the drained coolant and top up to the required level with mild lime water. Warm up the engine at medium speed and check the mounting location for leaks. Add coolant if necessary and close the expansion tank.

If the engine «boiled» - the cooling fan is to blame

Your Mondeo's cooling system handles smooth, long idling passages as well as strenuous mountain crossings. However, if the temperature rises to the boiling point, it is possible «striker» There is no fan here. Therefore, you do not need to immediately engage in towing a car: you should cool the engine and then quickly drive to the nearest workshop. Idling and slow driving in high gears is of course best avoided if possible. Your imaginary caution is not needed, as it will lead to engine heating, since the radiator is no longer «costs» in front of a headwind.

Attention: when the engine is stopped and warmed up while driving, the fan can work even when the ignition is switched off. Therefore, never mess around near the fan!