Replacement
1. Drain the coolant (see "Coolant - Replacement").
2. Remove the air filter (see "Air filter - removal and installation").
3. Using a Phillips screwdriver, loosen the clamps securing the two hoses to the thermostat pipes.
4. Disconnect the hoses from the thermostat pipes.
5. Using a 5 mm Allen key, unscrew the three thermostat housing tie bolts.
6. Disconnect the thermostat housing and remove the rubber sealing ring. We replace the damaged sealing ring.
7. Press and turn the thermostat spring stop plate...
... and we remove the thermostat actuator from the removed part of the housing.
Note: You can check the functionality of the thermostat by placing it in a container with water heated to a temperature close to the boiling point. The valve should open.
8. Assemble and install the thermostat in reverse order.
Removal
1. To remove the thermostat assembly, disconnect the two hoses from the thermostat cover pipes (see above 1-4).
2. Similarly, disconnect three more hoses from the thermostat pipes.
3. Disconnect the wiring harness from the coolant temperature sensor.
4. Using a 13 mm deep-head socket wrench, unscrew the nut securing the ground wire.
5. Using the same wrench, unscrew the two nuts securing the thermostat to the cylinder head.
6. Remove the thermostat from the studs and remove the sealing gasket.
7. If necessary, unscrew the coolant temperature sensor (see "Coolant Temperature Sensor - Checking and Replacing").
Installation
1. Install the thermostat in the reverse order, replacing the sealing gasket with a new one.
2. Fill the system with coolant (see "Coolant - Replacement").
3. Make sure there is no fluid leakage at the points where the hoses are connected to the thermostat. If necessary, tighten the hose clamps.