If a 2002 Peugeot 206 is currently experiencing overheating issues, the thermostat may be at fault. When the thermostat fails, the device can become immobile in the closed position, preventing engine coolant from circulating and resulting in the engine over heating. Replacing the thermostat is a relatively simple process. However, the engine coolant must be drained in order to remove the thermostat.
Open the bonnet and disconnect the negative terminal cable from the battery. Place a drain pan underneath the lower radiator hose.
Remove the cap from the engine coolant expansion chamber. Unfasten the clamp holding the lower radiator hose in place. Remove the lower radiator hose and allow the coolant to drain out of the radiator and expansion chamber. Reconnect the hose to the radiator when finished.
Locate the upper radiator hose and follow it along the right side of the engine bay until it ends at the thermostat housing on the engine block. Unfasten the clamp holding the upper radiator hose in place and disconnect it from the housing.
Use a ratchet and socket to remove the two bolts holding the housing in place. Remove the thermostat housing and set it aside. Note the orientation of the thermostat before removing it. The new thermostat must be installed in the same orientation as the old thermostat for a proper fit.
Remove the O-ring and the thermostat. Use a slotted screwdriver to scrape away any gasket residue left on the mounting surface.
Install the new thermostat in the same orientation as the old thermostat. Place the O-ring over the thermostat and place the housing over the thermostat. Reinsert the two retaining bolts and tighten them with the ratchet and socket.
Connect the upper radiator hose to the thermostat housing and reattach the retaining clip to the hose. Refill the expansion tank with the appropriate amount of fresh engine coolant as specified by the owner's manual.
Reconnect the negative terminal cable to the battery. Start the engine and check underneath the engine near the radiator and thermostat housing area for any leaks. Monitor the coolant level in the expansion tank and add more coolant as needed. Dispose of the old coolant in an environmentally friendly manner.
Most automotive repair shops will accept used engine coolant and other fluids for disposal. This service is usually offered free of charge.