Removing coolant expansion tank of high-temperature coolant circuit

Preliminary work

Refer to REMOVING THE FRONT UNDERBODY PROTECTION .
Refer to REMOVING THE UNDERBODY PROTECTION OF THE STEERING GEAR .

CAUTION: Materials harmful to health.
Contact with fluids harmful to health!

Note and follow safety instructions on containers.
Conduct all work in appropriate personal protective equipment only.

NOTE: TECHNICAL INFORMATION
Immobilization period-long fill of coolant!
Do not reuse used coolant.
When replacing and removing components which rely on the corrosion protection effect of the coolant, it is essential to change the coolant. The cooling system must therefore be emptied and refilled.
In the case of other removal work involving the draining of part quantities of coolant, the coolant level must be topped up with new coolant.

NOTE: TECHNICAL INFORMATION
Collect and dispose of emerging fluids. Observe country-specific waste disposal regulations.

Use commercially available disconnection tools to pinch off the coolant lines.

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Use commercially available syringe (1) or a suitable tool to empty the coolant expansion tank.

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Open the lid (1) on the coolant expansion tank for the high-temperature coolant circuit.
Suction the coolant with a standard pump from the coolant expansion tank for the high-temperature coolant circuit and dispose of it.

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Unlock plug connection (1) and disconnect.
Loosen the clamp (arrow).
Unlock the coolant expansion tank (2) for the low-temperature coolant circuit in the marked area.

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Feed the coolant expansion tank (1) for the low-temperature coolant circuit out of the holders and position.

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Unlock the holder (1).
Feed out coolant line (2) and place to one side.

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Unlock the coolant line (1) and pull off from the coolant expansion tank (4) for the high-temperature coolant circuit.
Unlock the coolant line (2) and pull off the coolant expansion tank (4) for the high-temperature coolant circuit.
Unlock lock (3).

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NOTE: TECHNICAL INFORMATION
Only flexible hose pipes may be disconnected.
Feed the coolant expansion tank (1) for the high-temperature coolant circuit upwards out of the holders and position.
Pinch off the coolant line (3) with a standard pinch-off tool (2).
Unlock and disconnect the coolant line (3).
Remove the coolant expansion tank (1) for the high-temperature coolant circuit.

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NOTE: TECHNICAL INFORMATION
Make sure that the connections are locked correctly. The locks must engage audibly.

Feed in the coolant expansion tank (1) for the high-temperature coolant circuit and position it.
Connect and lock the coolant line (3).
Remove the standard disconnection tool (2).
Insert and install the coolant expansion tank (1) for the high-temperature coolant circuit in the brackets.

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Ensure that the locking mechanism (3) engages audibly.
Connect the coolant line (2) to the coolant expansion tank (4) for the high-temperature coolant circuit and lock it.
The coolant line (1) must audibly engage.
Connect the coolant line (1) to the coolant expansion tank (4) for the high-temperature coolant circuit and lock it.
The coolant line (1) must audibly engage.

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Feed in and position the coolant line on the bracket (1).
Lock holder (1).

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Feed in the coolant expansion tank (1) for the low-temperature coolant circuit and position it.

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Insert and install the coolant expansion tank (2) for the low-temperature coolant circuit in the brackets.
The lock (3) must audibly engage.
Secure clamps (arrow).
Connect connectors (1) and lock.
The connector (1) must engage audibly.

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Loosen sealing cap (1).

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NOTE: TECHNICAL INFORMATION
Notes for working on the engine cooling system.
For additional information see: NOTES FOR WORKING ON THE COOLING SYSTEM .

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Adjust the fill level in the coolant expansion tank (2) of the high-temperature coolant circuit to the maximum mark (1).
Close sealing cap (1).
Close the sealing cap (1) until the arrows are flush.

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Follow-up work

Refer to INSTALLING THE UNDERBODY PROTECTION OF THE STEERING GEAR .
Refer to INSTALLING FRONT UNDERBODY PROTECTION .