Engine overheating is one of the most common serious malfunction problems faced by vehicle owners. If your vehicle overheats, permanent damage to engine parts may occur. Due to problems in the cooling systems of vehicles traveling in traffic, especially in the summer months, the engine temperature can rise rapidly and cause malfunction.
Overheating of the vehicle may be due to many reasons such as malfunction of cooling system components, lack of maintenance or operating errors. Correctly understanding the cause of overheating and intervening in time prolongs the life of the engine and prevents costly repairs.
What is Car Overheating?
Car overheating is when the engine rises above its normal operating temperature. Internal combustion engines generate high heat while running and the cooling system is activated to compensate for this heat. Under normal conditions, the ideal operating temperature of an automobile engine is between 90-100°C. If this temperature is exceeded, engine parts start to be damaged and vehicle performance decreases.
The first signal of overheating is usually a rise in the temperature gauge on the instrument panel. If the temperature gauge starts to move above 90°C or approaches red, the engine is at risk. If the vehicle continues to run at this stage, you may encounter serious and expensive problems such as gasket burnout and cracked engine block.
What Should the Car Temperature Gauge Be?
In modern vehicles, drivers can monitor the engine temperature thanks to the needle or digital display showing the engine temperature. The temperature gauge normally points to around 90°C, where the needle stops at the midpoint. This value indicates that the engine is running efficiently. However, if the needle rises above this point, the engine is overheating and should be checked immediately.
When the temperature gauge reaches red, this requires immediate intervention. Drivers should stop the vehicle in such a situation and wait for the engine to cool down. If this gauge fluctuates constantly, it may indicate a problem with system components such as the thermostat, radiator or water pump. It is vital to monitor the gauge regularly to understand the root of the problem.
What are the Causes of Car Overheating?
There can be many technical reasons for a vehicle to overheat. Factors such as problems in the cooling system, weather conditions or lack of engine oil can directly affect the engine temperature. Especially in urban traffic, these problems are more common on long journeys with stop-and-go. Some of the most common causes of overheating are radiator malfunction, water pump failure and cooling fan failure.
In addition, the thermostat not working properly, the temperature sender sending incorrect data or the vehicle being under excessive load are among the factors that increase the engine temperature. Using the air conditioner on in hot weather or choosing low-quality engine oil can also trigger overheating. Examining these causes in detail ensures timely and correct intervention to the vehicle.
Radiator Failures or Lack of Water
The radiator is one of the most important components that transfers the heat generated by the engine to the outside. If the radiator is blocked, cracked or the water level in it has dropped, the engine cannot be cooled sufficiently and the temperature rises. Lack of water is usually caused by leakage or evaporation and can cause serious damage if left unnoticed. This process can also be negatively affected if the radiator cap is not working properly.
As a driver, it is important to check your vehicle's water reservoir weekly for early detection of such problems. If you notice cracks in the radiator hoses, loosening of the clamps or water pooling at the bottom, you should take the vehicle to service immediately. Radiator problems, one of the most common causes of overheating, can often be fixed with simple maintenance.
Thermostat Failure
The thermostat plays an important role in the engine cooling system. Its job is to ensure that the engine reaches and maintains the ideal operating temperature. The thermostat, which is closed when the engine is cold, opens as the engine warms up and starts the flow of water to the radiator. However, if the thermostat fails, it can either remain completely closed or be stuck in the open position. If it remains closed, water cannot reach the radiator and the engine overheats.
When the thermostat fails, the engine temperature gauge suddenly rises, the heat balance is disturbed and the rest of the system is also affected. In this case, the vehicle usually overheats in a very short time. If you observe heating problems in your vehicle, it is vital to check the thermostat. Thermostat replacement is a relatively inexpensive and easy procedure, but without timely intervention it can put the engine at serious risk.
Water Pump (Recirculation) Malfunction
The water pump is the part that ensures continuous circulation of water between the radiator and the engine to cool the heat generated by the engine. It is also known as recirculation. When this pump is not working, the hot water in the engine block cannot reach the radiator and the engine heats up very quickly. Water pump failures usually occur as a result of broken pump impellers, disintegrating bearings or leaking gaskets.
If your vehicle has sudden temperature increases, water leaks coming from under the engine or strange rubbing noises while running, the water pump should be checked. Some water pump faults can also damage the engine belt over time. As a faulty recirculation pump can cause a high degree of damage to the engine, it should usually be replaced without delay.
Cooling Fan Failure
When the engine temperature exceeds a certain level, the cooling fan is activated to cool the water in the radiator. If the fan fails, this cooling does not take place and the engine overheats. This problem is usually caused by a malfunctioning fan motor, a blown fan fuse or a fan sender.
Fan failures are particularly pronounced in traffic jams because the fan's function becomes critical as the natural airflow is reduced. If the engine fan is not activated, the temperature gauge will rise rapidly. To check the fan, you can observe the engine temperature by idling the vehicle. If the fan does not activate when a certain temperature is reached, it may be faulty and should be intervened immediately.
Insufficient Engine Oil
Engine oil not only reduces friction, but also helps to cool parts of the engine. If the oil level drops or the oil loses its properties, it causes the parts inside the engine to heat up more. This indirectly increases the temperature. Especially in older vehicles, oil deficiency is common and often goes unnoticed, leading to overheating problems.
Checking your vehicle's engine oil level regularly can prevent this problem. If the dipstick reading falls below the minimum level, the engine is prone to overheating. Also, using oil with the wrong viscosity can cause the engine to overheat. For this reason, you should definitely follow the engine oil suitable for your vehicle and periodic changes.
Temperature Sender Fault
The temperature sender is the sensor that measures the temperature of the engine and transmits the information to the ECU and gauges. If this part is not functioning properly, the actual temperature of the engine is measured incorrectly and the fan activates late or not at all. As a result, the engine overheats without the user realizing it. Also, the temperature reading on the gauge does not reflect reality.
The most common symptom of a faulty sender is that the temperature gauge suddenly drops to zero or rises abnormally. A faulty sender can cause a chain failure, affecting not only the engine, but also the gauge and fan system. Usually a low-cost part, the temperature sender can be easily detected and replaced with regular checks.
Prolonged Stop and Start in Extremely Hot Weather
Long stop-and-go traffic in the summer months causes the engine temperature to rise. This is because the air flow is reduced, the engine is not revved and the fan and radiator system are more heavily loaded. Especially if the vehicle is traveling at low speeds, the cooling system may be inadequate without natural airflow.
In such cases, having the air conditioning on also increases the risk of overheating. If you are going to be in summer traffic for a long period of time, it may be useful to turn off the air conditioning, run the vehicle at low speed and, if possible, rest it in the shade. Such scenarios can lead to engine overheating, especially in older vehicles or cars with poor maintenance.
Use of Air Conditioner and Its Effect on Overheating
Air conditioning is a system that directly uses engine power and puts additional load on the engine when it is on. This can trigger overheating problems, especially in summer. If the engine is already running at high temperatures, the cooling system may be insufficient with the additional load from the air conditioner. In this case, the temperature gauge may go up.
If you notice that the temperature rises when the air conditioner is on, you can temporarily turn off the air conditioner to allow the system to relax. However, if this happens continuously, it may indicate another problem in the cooling system. Parts such as fans, radiators and thermostats should be checked. Remember, air conditioning does not directly cause overheating, but it can worsen the situation in a poor cooling system.
What to do if the car overheats?
When your car overheats, the first thing to do is to stop the vehicle immediately in a safe area and turn off the ignition. If the engine continues to overheat, it can cause permanent damage such as burnt gaskets, cracks in the engine block or piston damage. Open the hood immediately after stopping the vehicle, but never open the radiator cap when it is hot. Because high pressure hot water and steam can cause serious injury.
After waiting for the engine to cool down completely, you can check the water level in the radiator and water tank. If it is missing, water can be carefully added. However, this is only a temporary solution. A vehicle that overheats must be taken to a service center as soon as possible and the source of the malfunction must be examined by experts. The entire system must be checked to prevent overheating from recurring.
Stop the Vehicle Immediately and Turn Off the Ignition
When the temperature gauge suddenly rises or reaches the red level, it is necessary to pull the engine to the nearest safe area and turn off the ignition. As the vehicle starts, the engine temperature continues to rise and the cooling systems become ineffective. Stopping the vehicle is the first step to prevent further damage.
After turning off the ignition, the engine should be allowed to cool down on its own, avoiding methods such as pouring water around the engine or placing ice on it. Such sudden changes in temperature can cause cracks in the engine block. It is important that drivers remain calm and attentive for their own safety and that of the vehicle.
Open the Hood but Do Not Open the Radiator Cap
Opening the bonnet helps to dissipate the heat in the engine compartment more quickly. However, the radiator cap should never be opened when the engine is still hot. There may be over 1 bar of pressure inside the radiator and opening the cap will cause hot water to spray out. This can cause serious burns to the skin.
Wait at least 30 minutes before opening the radiator cap. After the engine temperature has dropped, it should be opened carefully by pressing on the cap with a cloth and turning it slowly. If the water is low, it should be topped up with distilled water or an antifreeze-water mixture. However, this is only a temporary solution, and a professional investigation should be carried out to determine why the system is draining.
Check Water Level After Engine Cools Down
After the engine has cooled down, check the radiator and expansion tank. If the water level is low, topping up the missing part can prevent the overheating from recurring. However, another issue to be considered here is why water is missing. If there is a leak in the system, putting water back in will not provide a permanent solution.
It should also be understood whether the missing water is due to evaporation or a leak. The radiator cap, hoses and water pump are the main components to check at this point. After adding water to the vehicle, the engine should be started and the gauge should be checked for an abnormal temperature rise.
Precautions to Prevent Overheating
Regular vehicle maintenance is of great importance to prevent overheating problems. First of all, the coolant level should be checked weekly. The liquid used in the cooling system should be a mixture of both water and antifreeze and should be used in a balanced ratio in summer and winter. Antifreeze is necessary not only in winter but also in summer as it raises the boiling point.
In addition, the thermostat, water pump, radiator and hoses should be checked periodically. Maintenance should be carried out in accordance with the service manual and engine oil changes should not be interrupted. The soundness of these parts should be checked and missing fluids should be completed, especially before setting off on a long journey. In addition, the use of quality engine oil and antifreeze is effective in maintaining the heat balance of the engine.
Regularly Checking the Coolant Level
One of the most effective ways to prevent the engine from overheating is to regularly check the water level in the expansion tank. This can be done weekly and is quite simple. The water level should be between the min-max levels on the container. If it falls below this level, the cooling system will not work efficiently.
If coolant is missing, it must be topped up with the appropriate antifreeze-water mixture. Adding only tap water can cause calcification and blockages in the system over time. In addition, if there is frequent water shortage, this may be a sign of a leak or malfunction in the system. In such a case, the vehicle must be taken to a service center.
Maintaining Periodic Maintenance
All parts used in the cooling system of the vehicle wear out over time and lose performance. For this reason, it is very important to have vehicle maintenance performed at the periods specified by the manufacturer. Parts such as thermostat, circulation pump, radiator cap and hoses should be replaced or checked on time.
Thanks to the checks performed during periodic maintenance, problems can be detected before they grow. This provides advantages in terms of both time and cost. Especially for older vehicles, this maintenance is even more critical. The most effective way to prevent overheating is to have the vehicle serviced regularly and not to neglect maintenance.
What are the Damages of Car Overheating to the Engine?
Car overheating is not just a temporary problem; without intervention, it can cause serious damage to the engine. The most common damage is a burnt cylinder head gasket. When this part burns, engine oil and water mix with each other and the engine becomes inoperable. Such situations may result not only in gasket replacement, but also in the complete dismantling of the engine.
Structural problems such as bending and cracking may also occur in the engine block. Pistons and piston rings may wear out and the crankshaft may deteriorate. This type of damage is very costly to repair and sometimes requires a complete replacement of the engine. Therefore, symptoms of overheating should be taken seriously and the engine should be protected with early intervention.
Cylinder Head Gasket Burnout
One of the most common and devastating effects of overheating on an engine is cylinder head gasket burnout. This gasket is the part that seals between the engine block and the cylinder head. When it burns, engine oil and coolant mix together, which prevents the engine from running properly. White smoke from the exhaust, reduced performance and foaming of the oil are symptoms of this problem.
In the event of a blown gasket, not only the gasket needs to be checked, but also the engine block. This process is both time-consuming and costly. If the gasket burns as a result of overheating, it may mean that the engine has to be overhauled again. For this reason, it is very important to turn off the ignition and stop the vehicle when the temperature indicator rises.
Engine Block Warping or Cracking
The engine block is one of the most fundamental parts of the engine. Due to overheating, this part heats up, expands and contracts again when it cools down. When this process repeats, cracking or warping can occur. This type of damage causes the engine to leak water and oil to leak out.
A cracked engine block is usually not repairable and the engine may need to be completely replaced. This can end the economic life of the vehicle. Knowing that overheating can have such devastating effects makes users more vigilant about early intervention.
