11 53 000 Removing and installing/replacing coolant thermostat (M52TU / M54 / M56)
Remove fan clutch with fan impeller and fan cowl. See 11 52 020 Removing and installing/replacing fan clutch (S52 / S54 / M52 / M52TU / M54 / M56)
Drain and dispose of coolant.
NOTE:
The water drain plug is located on the exhaust side on cylinder 2 in the engine block.
Installation:
Replacing sealing ring on water drain plug.
Tightening torque, refer to 11 11 5AZ in ENGINE - TIGHTENING TORQUES .
Vent cooling system and check for leaks.
Pull locks and disconnect water hoses.
Installation:
Refer to general instructions for work on cooling system.
Loosen nut (1).
Release screws on thermostat housing, remove thermostat housing.
Installation:
Keep sealing faces clean and free of oil.
NOTE:
Coolant thermostat is integrated in coolant thermostat housing and can only be replaced as a single unit.
Installation:
Replace seal (1).