To keep your BMW running at top quality, it is important to stay on top of regular maintenance. There are a number of easy things that you or your mechanic are able to check and maintain regularly to avoid any surprise fixes. Making sure that your BMW engine does not overheat is one way to ensure that you continue to have enjoyable driving experiences. The temperature gauge located on the gauge cluster that will notify you if you are in danger of overheating your BMW’s engine, and you will want to stop driving as soon as possible if you suspect your engine may be reaching a high temperature.
Possible Reasons for High Engine Temperatures
Although there are a number of very specific reasons your engine could be experiencing high temperatures, there are four very common culprits. The engine has a cooling system in place to regulate temperatures, so if there is a flaw in the cooling system, there is a possibility the BMW’s engine could overheat.
If the engine overheats, it can cause damage to the engine, and if the engine is ruined, you are in for a pricey fix. When an engine overheats for an extensive period of time, you run a high likelihood of blowing a head gasket or even cracking the cylinder head on the engine. The four most common reasons for high engine temperatures include low coolant levels, pockets of air in the cooling system, cooling fan malfunction, or debris in the radiator.
Low Coolant Levels
You can access the engine coolant tank or sometimes in the coolant compartment in the radiator. If you suspect that you are running the risk of overheating the engine, it is a good idea to monitor the coolant levels. If you are checking the coolant in a tank separate from the radiator, there should be a mark on the side of the tank to tell you if you are low on coolant or not.
The coolant level will be different when the engine has been running and is hot or if you are checking before driving. However, manufacturers planned for this and put both hot and cold level markings to check engine coolant levels. Be sure that you wait a few hours after having the engine running to check coolant that is stored directly in the radiator. While the engine is running, it pressurizes the radiator, and if you open the radiator coolant compartment when the engine is hot, it will explode, releasing hot liquid.
Once the engine has had ample time to cool and you check the coolant levels in the radiator compartment, the coolant level should be to the top of the tank. You will want to add coolant to either tank system if your coolant appears to be at a low level.
Air in Cooling System
If you have checked the coolant level and they are at the appropriate level, then you will want to consider any of the other three possibilities. Having air in the cooling system will be more likely if you experience intermittent or random engine overheating or if your temperature gauge goes up when idling. There isn’t a good way to check and see if there is air in the cooling system, but if you suspect there is, the system will simply have to be bled. Bleeding means taking the air out of the cooling system. Depending on the engine model, there are different ways to bleed the air out. Check with a trusted mechanic if you are unsure on how to bleed your coolant system.
Cooling Fan Malfunction
When you begin to notice that the temperature gauge goes up when at an idle and then goes back down when you begin to drive, you may have a cooling fan malfunction. The fan ensures that air is pulled through the radiator to keep the radiator components cool. If the fan isn’t working, air is able to flow through the radiator when you drive, but not when you are idling. That would be why the temperature gauge goes up in an idle position.
To check the fan, look under the hood of your BMW to see if the fan is on or not. However, electric fans turn on and off, so the fan will only be running if your engine begins to overheat. Mechanical fans will always be turning if the engine is running. If you have an electric fan, you may need to let your engine idle until it is heated up to see if the fan turns on.
Debris Blocking Airflow
Another likely culprit of high engine temperatures is having debris in the radiator blocking the airflow. This is usually more likely if you drive off of pavement frequently. This will cause overheating every time you drive. If your coolant levels are good and the fan is running, you will want to see if there’s debris blocking airflow in the radiator.
One easy way to check this if the fan is running is to hold a piece of paper up to the open part of the grill and let go of the paper. If the paper gets sucked onto the grill, there is proper airflow happening. If not, then you will want to wait for the radiator to cool and then check to see if there is a build up of debris. Usually you can wash out the debris with a water hose or remove it by hand.
Trust the Professionals
If you live in or around Longhorn or San Antonio, Texas, consider consulting Autobahn Automotive services for any and all questions regarding your BMW. If you are unsure why your engine is experiencing higher than normal temperatures, Autobahn Automotive is the perfect resource to answer your specific questions or to take a look at the engine for you.