Drain the engine coolant.

Remove the lower hose, then remove the thermostat.

Install the thermostat with a new O-ring, then install the lower hose.

Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open.

Drain the engine coolant.

Remove the lower hose, then remove the thermostat.

Install the thermostat with a new O-ring, then install the lower hose.

Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open.