Bleeding Cooling System & Checking For Water Leaks

Venting Cooling System And Checking For Leaks (Z3 M54)

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

Check cooling system for leaks.
Top up coolant.

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






1. Open cap on coolant expansion tank.
2. Turn on ignition
3. Set heating controller to maximum temperature
4. Set blower to low setting. This opens the heating valves and starts the auxiliary water pump.
5. Carry out filling procedure slowly
6. Close vent plug (1) when bubble-free coolant emerges






7. Pour coolant into expansion tank up to max. cold fill level. Marking (2) is then level with upper edge of coolant expansion tank.
8. Close coolant expansion tank
9. Allow engine to warm up until thermostat opens

Allow engine to cool down before checking coolant level.

Coolant temperature must not exceed 30°C. If ambient temperature exceeds 30°C, allow engine to cool down at least to ambient temperature.

Carefully opern sealing cap and check fluid level. Fluid level is OK when top edge of coolant expansion tank is between markings (1 and 2) on float needle.

- Minimum cold fill level
Top edge of coolant expansion tank is level with marking (1)

- Maximum cold fill level
Top edge of coolant expansion tank is level with marking (2)

If necessary, top up coolant

Note: The tank mark indicates the fluid level at approx 20±C

Use only recommended coolant