You should always bleed the cooling system after draining it or opening it somewhere other than the expansion tank. By bleeding the system, you can make sure there are no air pockets and the coolant can function as it should. It’s an electric pump, thus the bleeding procedure requires a powerful battery. We finished the procedure without a battery charger, despite the BMW repair manual’s recommendation.
The self-bleeding technique should be started by:
The bleeding can then be started by depressing the accelerator pedal for roughly 10 seconds. When you hear the coolant within the engine and radiator moving, you’ll know the procedure has started. Once it has begun, let the car alone for 8 to 10 minutes. After that, the procedure will be finished, and your cooling system will be totally bled and ready for use.
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owner of a 1973 Porsche 914 and a 1998 Impreza 2.5RS with a flat-six engine swap. only when opposing perspectives are horizontal.
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danielw05
My coolant system has to be “burped,” therefore I conducted some research and put the procedures below together. However, I still require a little assistance to make sure that I am not misguiding others. What should be done following stages 1 through 5? Is it time to put the resevoir cap on now? Should the cap be inserted first, then the car should be switched off? After doing this, should you immediately start the automobile or should you turn it off? I have read that in order to propel the bubble along, you should either do this on a very steep hill or jack the front end up at a decent angle. On the other side, I read a few forums where doing this wasn’t mentioned. Please let me know if I’m on the right road or not.
I would greatly appreciate any assistance. :thumbsup:
1. Start the engine and give it plenty of time to warm up. Take it around the big block a few times, if possible.
2. Do not replace the resevoir lid after filling the coolant to the top of the line.
3. Set the car’s heater to its highest setting, which is red (hot). Refill the coolant to the top of the line once the thermostat opens.
4. Remove the bleed screw, which is situated on the thermostat housing’s top. Allow the coolant and air bubbles to exit the bleeder until only antifreeze remains.
5. Reinstall the bleed screw and screw it down.
How to bleed a water pump that is mechanical (older BMWs)
Tools Required:
- Jack (depending on model)
- Jack postures (depending on model)
- the screwdriver
- Auto Key
How can you tell if your water pump is mechanical? A mechanical water pump is almost probably present in a BMW that was built before 2004. With the E90 in 2004, BMW started adding electric water pumps on the 3 Series. The E46, E36, and E30 are belt-driven mechanical water pumps, as are all prior 3 Series models.
These older BMW models require manual bleeding. Even while it’s a fairly quick and simple process, it does require more patience and time than versions of electric water pumps that “self-bleed.” These automobiles have mechanical water pumps, thermostats, and reservoirs positioned on the radiator’s side.
**To lift the front end of these vehicles, I utilize a jack, jack stands, or ramps. Why? Because the bleed screw and radiator are now the highest points on the coolant system, this will let the air move more easily. The majority of people don’t do it, but in my experience, it’s the best approach to guarantee that all air bubbles are eliminated from the cooling system.
**This bleed method will still function flawlessly if your heater is broken. I’ve done this procedure a lot of times when someone’s a/c control module has failed. Simply omit the step requiring you to turn on the heat.
- Put the front end on ramps or jack it up. (This step is advised but not necessary.)
- Open the bleed screw, then add coolant until it reaches the fill line. Take off the fill cap.
- Set the fan speed and the heat to their highest settings.
- The engine should be started and given time to reach working temperature. Release air when it heats up by loosening the bleed screw, then tighten it again.
- Reinstall the fill cap and tighten it firmly. Press the gas pedal to increase the engine’s rotational speed to 2000–2500 RPMs. If your heat works, it should be pumping hot air at this stage at full force. You can see from this that the heater core is dripping with coolant.
- After tightening the bleed screw, setting the car down and giving it a short spin, you’re done!
How long does the coolant system need to burp?
It takes time and persistence to burp an automobile cooling system. Burping might take up to an hour, depending on the volume of air in the cooling system and the make and model of your car.
However, it takes the engine 5 to 10 minutes to reach the normal operating temperature. The thermostat will turn on at this point to allow coolant to reach the engine.
Which coolant does the BMW F30 employ?
In your cooling system, BMW’s blue G11 coolant is intended to encourage heat transfer and prevent corrosion. Nitrate and phosphate are not present in genuine BMW coolant. Be aware that before putting BMW coolant to the car, it must be diluted with distilled water to a 50:50 combination.
What occurs if BMW fails to bleed the coolant?
My 2014 335i gt’s radiator vent line broke, leaking some coolant, therefore I had to follow the instructions for bleeding the system after adding the coolant back in.
If anyone knows why they don’t just instruct you to put the engine on and drive about to let the air out, please let me know.
I have some ideas, but I’m curious if someone here who is “in the know” could clarify this.
You can’t fully fill the system with coolant if the air hasn’t been bled out. The hoses will contain air entrapment areas. If the engine and transmission are operated, they may overheat and destroy a variety of parts, beginning with the water pump and becoming worse from there.
No, the purpose is to remove air from the system. Since the system is sealed, any trapped air will remain there unless it is purged. For this reason, the coolant must also be injected under pressure into the circuit. This Oldsmobile is not your father’s.
Oh, I understood what bleeding was and why it was necessary. I apologize if I was unclear.
My concern related to how BMW decided to handle it. My friend and I are discussing how you bleed the system on a BMW as opposed to another kind of automobile. He believes that BMW’s process is overly complex. Procedures like these don’t exist simply because they do, thus I believe there is a strong rationale for it.
So here’s my inquiry: what design issue was BMW attempting to address by developing a method for bleeding the coolant circuit while the engine is not running?
I don’t necessarily see a design issue. If you wait for the engine to reach operating temperature before the cooling system can purge trapped air, damage may occur before the air exits the system since coolant doesn’t circulate through the system completely until then. That cannot occur if the air is purged without starting the engine.
He is referring to a thermostat; once the coolant reaches the desired temperature, the thermostat opens, and the coolant circulates throughout the entire system.
Don’t forget to fully activate your heater so that the water can also pass through the heater core.
No car, not even an Oldsmobile or a Honda, can be bled by just driving it around; instead, a bleeder screw is located at the highest point of the cooling system, or the overflow/radiator cap is used.
What is the time required to bleed coolant on a BMW?
Depending on the model and approach you use, it typically takes 15 to 30 minutes. However, heating the engine and draining the coolant both take about 15-20 minutes.
Between the overflow tank and thermostat, your cooling system can leak a little. However, you must fill the coolant and drive the vehicle with the radiator cover off in order to fully bleed.
The water needs to be turned on and adjusted to run slowly. To remove the radiator from the cooling system, turn off your car.
How can I tell if the thermostat in my BMW is broken?
The following symptoms indicate a faulty automobile thermostat: The engine overheats and the temperature indicator reads high. Temperature swings are frequent. The vehicle’s coolant seeps under the car or near the thermostat.
What steps may be taken to avoid having air become sucked into the cooling system?
What steps may be taken to make sure air doesn’t become stuck in the cooling system when the coolant is changed? While adding coolant, use the coolant exchange machine that creates a vacuum in the system or open the air bleeder valves.
What increases the cooling system’s pressure too much?
The solution is heat. When a liquid or gas that is trapped in an enclosed space is heated, it expands and builds pressure. The cooling system in your car uses the same refrigerant.
Why does the cooling system in cars get airlocked?
Your automobile may have overheated for a variety of reasons, but inefficient cooling is frequently the root of the problem. Your engine’s cooling system is essential to its efficient running. Your cooling system uses the circulation of coolant or antifreeze to dissipate heat from your engine. The cooling system in your car is incredibly intricate and relies on the engine as well as the radiator, heater core, thermostat, water pump, and hoses to perform its essential function.
Your cooling system’s leaks are frequently to blame for an overheating engine. Leaks allow air into the system in addition to obstructing coolant circulation. Large bubbles that cannot be forced through the system form as a result of “airlock,” which happens when there is air in the cooling system. Airlock can significantly reduce coolant flow, causing heat that should be dispersed to remain inside the engine. Similar results occur when your cooling system becomes blocked, with the engine overheating as a result of poor circulation. Foreign items and mineral build up are two major reasons for blockages.
Overheating may occur if a water pump fails. The water pump is crucial to the operation of every cooling system because it keeps the coolant flowing. Engine overheating may occur as a result of a broken or worn water pump, which can happen over time. Overheating is frequently the fault of the coolant. The dip in temperature, particularly during the winter, can cause coolants to vary in consistency. In colder climates, your coolant may turn gel-like, restricting circulation and possibly causing blockages. Car overheating can also be brought on by something as straightforward as low coolant levels.
How can you tell whether your cooling system is running on air?
One of the many indications that there are air pockets in the coolant system is a broken car heater. There won’t be any heat coming from the vents when you turn on the car heater. The air could not be forced out because of the air bubbles. Hot fluid cannot enter the heater core because of the trapped air.