Contents: Removal ↡ Installation ↡
Removal
The thermostat is built into the thermostat housing and is replaced as a single unit.
Caution! When the engine is hot, place a thick cloth on the radiator filler cap before removing it to avoid being burned by hot coolant or steam. Remove the cap only when the coolant temperature is below +90°C.
1. Drain the coolant from the system.
2. Cars with petrol engine. Remove retaining ring 2 and remove temperature sensor 3 from thermostat housing 1 (see illustration).
3. Vehicles with diesel engine. Remove the diesel fuel system temperature sensor.
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4. Cars with a gasoline engine. Disconnect coolant hoses 4 and 5 from the thermostat housing. Before doing this, loosen the hose clamps and move the clamps onto the hoses (see illustration 4.2).
5. Vehicles with diesel engines: Disconnect the three coolant circulation hoses from the thermostat housing.
6. Unscrew bolt 6 of the fastening and remove the thermostat housing together with the thermostat from the cylinder head (see illustration 4.2).
7. Remove the sealing ring from the thermostat housing and clean the sealing surfaces.
Installation
8. Install a new sealing ring onto the thermostat housing and secure it to the cylinder head.
The tightening torque of the thermostat housing mounting bolt on the cylinder head is 9 Nm.
9. Place the coolant hoses on the fittings and secure the hoses with clamps.
Caution: Before installation, inspect the hoses and clamps to ensure they are not damaged.
10. Install the temperature sensor with a new sealing ring into the thermostat housing and secure it with a retaining ring by putting it on the side.
11. Fill with new coolant and bleed the cooling system, after checking the coolant concentration.