Checking the functionality of the thermostat can be done on the vehicle. After starting a cold engine with a working thermostat, the lower radiator hose should begin to heat up at a coolant temperature of 80-85°C (the pointer of the liquid temperature gauge is in a vertical position). Otherwise, remove the thermostat and check the temperature at which the main valve opens and its stroke.
Removing
Attention! Remove the thermostat only when the engine is cold.
1. We install the car on a viewing hole or overpass (see "Vehicle preparation for maintenance and repair").
2. Drain the coolant (see "Coolant - level check and replacement").
3. Use a round-nose pliers or a slotted screwdriver with a thin blade to loosen the band clamp securing the hose coming from the radiator.
4. Disconnect the hose from the thermostat inlet.
On cars of recent years of production, the hoses are fastened to the thermostat nozzles with band clamps, and to the coolant pump and cylinder head nozzle - with worm gears. In this case, it is more convenient to loosen the worm clamps and remove the thermostat together with the hoses.
5. socket wrench by 8 mm or use a Phillips screwdriver to loosen the hose clamps to the pipes of the coolant pump and cylinder head.
6. Remove the thermostat and disconnect the hoses from the nozzles.
To check the thermostat, place it in a heat-resistant container with water. We heat the water and use a thermometer to control the temperature at which the main valve opens. If this temperature is not in the range of 80.6-81.5°C, the thermostat must be replaced.
Installation
1. We put the hoses on the thermostat nozzles.
2. Install on the hose and instead of tape clamps - worm, without tightening them.
3. We connect the hose coming from the radiator to the lower inlet of the thermostat and tighten the clamps.
4. Fill in the coolant (see "Coolant - level check and replacement") and, starting the engine, check for leaks.