Removing and installing/replacing the high-temperature coolant expansion tank (B46/B48 4-Cyl. Engine) (4' Series Coupe/Convertible, 4' Series Gran Coupe Sedan)

Recycling 

Collect and dispose of escaping coolant using a suitable container.

Observe country-specific waste disposal regulations.

Observe the NOTES  about repairs on the cooling system.

Necessary preliminary work: 

• Remove DESIGN COVER .
• Remove the front strut on the left (F33 only)  .
• Disconnect coolant hoses from coolant expansion tank.

Removal: 

Release the sealing cap (1) at the high-temperature coolant circuit.

Release the sealing cap (2) at the low-temperature coolant circuit.

Draw off coolant with standard pump  .

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Unlock and loosen the coolant lines along the arrows.

Unlock and loosen the locks (1).

Remove the expansion tank (2) from the rubber mounts.

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Unlock and release connector on coolant level switch (1).

Unlock coolant line (2) and release.

Collect and dispose of escaping coolant.

Lift out expansion tank (3).

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Unlock the expansion tank (1) and loosen from the expansion tank (2) in the direction of the arrow.

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Preparation for installation: 

Check the rubber mount (1) is positioned correctly.

Check the holder (2) is positioned correctly.

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Check the rubber mount (1) is positioned correctly.

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Installation: 

Insert and install the expansion tank (1) in the expansion tank (2) in the direction of the arrow.

Expansion tank (1) must engage audibly.

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Connect and lock the coolant line (2) on the expansion tank (3).

Coolant line (2) must audibly engage.

Connect and lock the connector (1) on coolant level switch.

Connector (1) must engage audibly.

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Thread and install expansion tanks (1) in latch mechanism (2).

Expansion tank (1) must engage audibly.

Connect and lock the coolant line along the arrows.

The coolant lines must engage audibly along the arrows.

Top up coolant level up to maximum  .

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Close sealing cap (1).

Close sealing cap (2).

Close sealing cap (1) until arrows  align.

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Required follow-up work: 

• Install the DESIGN COVER .
• Install the front strut on the left (F33 only)  .