17 00 039 Venting cooling system and checking for leaks

WARNING: This page is about a different car, the 2010 BMW X3, 2009 BMW X3, 2008 BMW X3, and 2007 BMW X3. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Danger of scalding!
Only perform these tasks on an engine that has cooled down.

Necessary preliminary tasks:

Draining coolant:

The procedure is described in the section Draining and adding coolant. See 17 00 005 Draining Off And Topping Up Coolant .

NOTE: Use only recommended coolant.

IMPORTANT: Fill coolant expansion tank up to lower edge of filler neck with recommended coolant. Pour in coolant slowly. Close vent screw (2) when bubble-free coolant emerges Close cap on expansion tank. Do not open the coolant expansion tank cap during the venting procedure.

Adding coolant:

To ensure the cooling system is properly vented, it is absolutely essential to follow the steps below:

Open cap (1) on coolant expansion tank.
Open vent screw (2). Connect battery charger. Switch on ignition.
Set heater control to maximum temperature. Activate "Automatic" button, then reduce fan to lowest setting.
Press accelerator pedal for 10 seconds to floor. Engine must not be started.
The venting procedure is started when the accelerator pedal is pressed and takes approx. 12 minutes.
Check cooling system for leaks.

Fig 1: Opening Coolant Expansion Tank Cap
Courtesy of BMW OF NORTH AMERICA, INC.
If the venting procedure has to be carried out several times, allow DME to drop completely (ignition key removed for approx. 3 minutes), then repeat from step 3.

Fig 2: Locating Expansion Tank Coolant Filling Mark (E 65/E 66 Shown) (1 Of 2)

Courtesy of BMW OF NORTH AMERICA, INC.

Checking coolant level:

CAUTION: Check coolant level at a maximum coolant temperature of 30°C.

NOTE: If ambient temperature exceeds 30°C, allow engine to cool down at least to ambient temperature.

Open cap carefully.

Fluid level is O.K. when top edge of coolant expansion tank is between both markings (1 and 2) on float needle.

Minimum cold fill level:

Upper edge of coolant expansion tank is level with marking (1).

Maximum cold fill level:

Upper edge of coolant expansion tank is level with marking (2).

If necessary, top up coolant.

NOTE: Tank mark indicates the fluid level at approx. 20°C.

Check cooling system for leaks. See 17 00 009 Checking Cooling System For Leaks (M54) .

Fig 3: Locating Expansion Tank Coolant Filling Mark (E 65/E 66) (2 Of 2)

Courtesy of BMW OF NORTH AMERICA, INC.