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Thermostat Replacement

Model: Peugeot 406 MK 1 - Years 1995-2005
Part: Thermostat

Perform this maintenance operation with the engine cold: open the bonnet and unscrew the cap of the coolant reservoir; then place a container under the radiator to collect the fluid, remove the plastic cover of the engine, and unscrew the bleed plugs of the cooling system. Next, detach the hose located under the radiator to allow complete drainage of the fluid. Also detach the upper hose to connect a water hose for complete flushing of the circuit. Locate the thermostat and remove it to spray water inside it as well. Install the new thermostat, reconnect the hoses, and fill the system from the reservoir with the appropriate coolant until it flows from the bleed plugs, which should then be tightened. Start the engine and check the activation of the cooling fan, then recheck the fluid level in the reservoir.

Updated on 7 February 2026 by ScegliAuto

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