1. Drain the engine coolant.
2. Loosen the radiator drain plug completely.
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3. Using a flathead screwdriver or equivalent, pry out the radiator drain plug.
Caution: Do not apply excessive force to the flathead screwdriver or equivalent as doing so can damage the drain bore. Slowly and carefully pry out the radiator drain plug when removing it.
4. Install a new radiator drain plug with a new O-ring.
Tightening torque 1.2 - 1.5 Nm (13 - 15 kgf-cm, 11 - 13 in-lbf)
5. Add engine coolant.