- Inspection pit or hydraulic garage lift with stands.
- Ring wrench or head.
- Coolant container.
- Antifreeze. In this case, only brands of antifreeze approved by BMW are allowed to be used. Please refer to Specifications. Attention: Do not mix antifreeze of different brands.
- Clean, low lime content drinking quality water.
- The drain plug on the cylinder block requires an aluminum O-ring A 14 x 18.
As part of maintenance, it is necessary to change the coolant every 4 years. Caution: The coolant is poisonous to a certain extent and should not be simply discarded. Local authorities should provide information on the location of collection points for such materials.
The volume of the cooling system is given in Specifications.
Coolant Removal
Do not open the cap when the engine is hot. There is a risk of burns! Open the plug only when the coolant temperature is below +90°C. When opening the cork, place a rag on it.
1. Carefully open the expansion tank cap.
The operation of lifting and placing the vehicle on stands is dangerous! Therefore, before carrying out the operation, read Section Jacking and towing.
2. Raise and place the vehicle on stands. Remove the lower cover of the engine compartment, refer to Section Removal and installation of the bottom cover of an impellent compartment.
3. Place a clean container under the radiator and unscrew the plug below the radiator, while holding the adjusting nut -2-. Engines 316i, 318i also have a separate drain plug -3- for the expansion tank, which must also be opened.
4. In addition, place a container under the engine and unscrew the drain plug on the cylinder block. The plug is under the exhaust manifold.
5. Completely drain the coolant and dispose of it according to existing procedures.
6. Screw the drain plug with a new sealing ring into the cylinder block and tighten to 25 Nm.
7. Screw in the drain plug on the radiator with a new sealing lightly tighten it to 2.5 Nm.
Filling the system with coolant
8. Set the heater in the passenger compartment to maximum power. Set the fan switch to low and turn on the ignition. Thus, the heater taps open.
9. Open the air outlet at the top of the radiator next to the expansion tank.
10. Petrol engines: Fill the expansion tank to the brim with fresh coolant so that the coolant comes out free of bubbles through the bleed screw. Close the fitting.
11. Loosen the screws -1- and remove the engine cover -2-. In the illustration, both left screws are equipped with socket wrenches for an internal hexagon.
12. Loosen the union for removing air -1- on the radiator of the exhaust gas recirculation system and the union -2- of the oil-water heat exchanger.
13. Loosen the air removal fitting -1- on the heater hose.
14. 320d engine with A/C: Loosen the bleed screw -1- on the hose leading to the heater heat exchanger.
15. For a diesel engine, it is imperative to observe the following sequence of filling the system with coolant:
- a) Slowly fill the expansion tank with fluid. Close the fitting -2- of the oil-water heat exchanger when liquid emerges through it.
- b) Keep adding liquid. Close the fitting -1- next to the expansion tank when liquid comes out there.
- c) Fill the expansion tank with liquid to the brim.
- d) Close the remaining fittings on the heater hose, recirculation radiator and, if air-conditioned, on the heater heat exchanger hose.
16. Close the expansion tank with a stopper. Do not warm up the engine with the plug open, as this may cause damage.
17. Start the engine and keep the speed above 2500 rpm by jerking the gas pedal. As a result of removing the air contained in the coolant, the level of the liquid in the tank will drop slightly.
18. Turn off the ignition.
If necessary, add coolant to the system only after the engine has cooled down, otherwise there is a risk of burns after removing the plug!
19. Check up liquid level on the cold engine and if necessary add, address to the Section Checking fluid levels.
20. Visually check the tightness of the cooling system, in particular the hose connections, as well as drain plugs and bleed fittings.
21. Diesel engine 320d: Install and secure the engine cover.