How to Bleed the Coolant in a BMW 320li?

[MadelineDella]

For the BMW 320li, after adding coolant, open the coolant filler port and start the vehicle, maintaining this state for a few minutes to bleed the system. Below are detailed steps regarding bleeding the coolant in a BMW 320li: 1. Precautions: The coolant used in the vehicle requires regular inspection and periodic replacement. When replacing the coolant, ensure to use the same brand and model as the original coolant. 2. Vehicle Specifications: The BMW 320li is a mid-size sedan, also known as a B-segment car. It features a MacPherson strut front suspension and a multi-link independent rear suspension.

[OBrayden]

I have hands-on experience with this. The bleeding process after replacing the coolant on a BMW 320Li is quite particular, especially with that electric water pump. First, park the car on level ground and open the expansion tank cap when the engine is cool. Remember to turn the key to the ON position but don't start the engine - set the AC to maximum temperature and minimum fan speed, which is crucial as the electric water pump will activate automatically for bleeding. Wait until bubbles stop emerging from the radiator neck, then start the engine and let it idle for about ten minutes. Keep an eye on the temperature gauge - if it rises rapidly, shut off immediately as this indicates incomplete bleeding. Finally, top up the coolant to the middle level mark, drive about two kilometers, then recheck the level. The whole process takes about twenty minutes, and skipping any step could easily lead to abnormal coolant temperature.

[VanCollin]

Last week, I just helped a friend bleed the cooling system on his G28-generation 320Li. The key is to operate in stages: When the engine is cold, first loosen the expansion tank cap to release pressure, then tighten it and add new coolant up to the MAX line. Turn on the ignition without starting the engine, and simultaneously press the accelerator for 30 seconds to activate the water pump's self-bleeding mode—you'll hear gurgling sounds at this point. After that, start the engine and let it idle. Before the coolant temperature reaches the midpoint, turn the heater to maximum setting until hot air blows out, indicating the heater circuit is clear. When topping up the coolant, add it slowly in three stages because the fluid level will drop on its own. Finally, be sure to test-drive the car to verify, paying special attention to whether the coolant temperature remains stable during uphill driving.

[DanteAnn]

The safest operation procedure consists of four steps: First, open the cap when the engine is cold and fill to the MAX line, then let it sit; second, turn on the ignition, activate the heater and set to internal circulation; third, start the engine and wait for the fan to rotate; fourth, repeat the coolant replenishment until it stabilizes. A reminder: only use BMW-certified blue coolant, as mixing different colors can cause gelation. Do not randomly loosen the vent bolt at the lower corner of the radiator during bleeding, as it is prone to thread stripping. It's best to have two people cooperate during the entire operation: one in the car pressing the accelerator to monitor the water temperature, and the other observing the bleeding situation.

[Noelle]

When performing the operation yourself, pay special attention to the cooling system pressure of 1.5Bar, and it must be done on a cold engine! Prepare a funnel and insert it into the coolant reservoir port. After starting the engine, lightly press the accelerator to maintain 2000 RPM. Slowly add the coolant at this time, and you will see bubbles continuously emerging. The key point is to turn on the heater when the water temperature reaches 90°C and check the air outlet temperature. After the electric fan runs at high speed, turn off the engine, wait for it to cool completely, and then top up the coolant to the midline. Don't forget the clicking sound when sealing the cap; if it's not securely fastened, it may leak slowly. It is recommended to take before-and-after photos of the water temperature for comparison.