Removing and installing/replacing coolant expansion tank

WARNING: This page does not describe the selected car, but rather 37 other vehicles, including the 2006 BMW 330Ci, 2005 BMW 330xi, 2005 BMW 330i, 2005 BMW 330Ci, and 2005 BMW 325xi. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Danger of scalding. Only carry out repair work on the cooling system after the engine has cooled down.

Follow INSTRUCTIONS FOR REPAIR WORK ON COOLING SYSTEM
Remove INTAKE FILTER HOUSING
Remove front underbody protection.
DRAIN COOLANT FROM RADIATOR

Unfasten plug connection (1) and disconnect.

Fig 1: Disconnecting Plug Connection At Level Sensor

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Pull out lock (2).

When replacing coolant expansion tank:

Unlock coolant level sensor (1) by turning and pull out of coolant expansion tank.

Fig 2: Unlocking Coolant Level Sensor By Turning

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Pull locks (1 and 2) upwards and detach coolant hose from radiator/coolant expansion tank.

Fig 3: Pulling Locks Upwards And Detaching Coolant Hose From Radiator/Coolant Expansion Tank

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Pull lock (1) upwards and detach coolant hose from coolant expansion tank.

Fig 4: Pulling Lock Upwards And Detaching Coolant Hose From Coolant Expansion Tank

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Pull coolant expansion tank a little out of retaining plate and lower connection piece. Then tilt expansion tank to rear and remove.

Installation:

Check O-rings. Under no circumstances coat O-rings with antiseize agent prior to installation.

Retaining lug must engage in opening in retaining plate.

Fig 5: Removing Expansion Tank

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