17 00 039 Bleed cooling system and check for watertightness (N55)

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WARNING: Risk of scalding!
Open sealing cap only after engine has cooled down.

IMPORTANT: Electric coolant pump: follow INSTRUCTIONS FOR REPAIR WORK ON THE COOLING SYSTEM .

IMPORTANT: Lifetime coolant filling. Never 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 drained and refilled. In the case of other removal work involving the draining of part quantities of coolant, replace these quantities which have been drained with new coolant.

Only when refilling!

Use only recommended COOLANT .

Observe appropriate water/antifreeze mixture ratio.

Perform filling operation slowly.

Adjust coolant level to maximum.

Fig 1: Checking Coolant Level

Courtesy of BMW OF NORTH AMERICA, INC.

Close coolant expansion tank.

Installation note:

Close the sealing cap (1) until the arrows line up.

Fig 2: Identifying Coolant Expansion Tank Sealing Cap

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: The following bleeding procedure is necessary e.g. when a part is replaced in the cooling system or when the cooling system is refilled.

Adding coolant:

Cooling system must be filled with a VACUUM FILLING UNIT only!

Use only recommended COOLANT .

Observe appropriate water/antifreeze mixture ratio.

Fig 3: Checking Coolant Level

Courtesy of BMW OF NORTH AMERICA, INC.

Venting cooling system:

NOTE: Leave the coolant expansion tank sealing cap open during the bleeding procedure.

Switch on the low-beam headlights to perform the bleeding procedure. If the low-beam headlights are not switched on, the ignition (Terminal 15) will switch off automatically after a certain period of time and interrupt the bleeding procedure.

Connect battery charger.
Switch the ignition on.
Switch on low-beam headlight.
Set heater to maximum temperature and turn blower down to lowest speed.
FES (driving experience switch) must not be in ECO PRO!
Press accelerator pedal for 10 seconds to floor. Engine must not be started.
The bleeding procedure was started by pressing the accelerator pedal and takes approx. 12 min. (the electrical coolant pump was activated and switches off automatically after approx. 12 min).
Then adjust fluid level in the coolant expansion tank to maximum.
CHECK cooling system on watertightness.
If venting has to be carried out again (e.g. if cooling system is leaking), allow DME to fall completely (leave ignition key removed for approx. 3 mins.), then repeat from Point 2.

Close coolant expansion tank.

Installation note:

Close the sealing cap (1) until the arrows line up.

Fig 4: Identifying Coolant Expansion Tank Sealing Cap

Courtesy of BMW OF NORTH AMERICA, INC.