Ducati MONSTER 821 Workshop Manual page 111

Slide out clamp (4), disconnect hose (5) and allow all coolant to drain in a container.
Loosen plug (6) from fluid drain hole located on the pump cover.
Allow the coolant to drain off completely.
Screw plug (6) in the fluid drain hole with a new seal.
Tighten plug (6) to a torque of 20Nm ± 10%.
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