When the driver does not notice that heat-upModern cars are equipped with many sensors, but relying solely on the light bulb on the dashboard is a risk that can lead to jamming of pistons. Understanding the physiological signs of a malfunction allows you to react before the temperature indicator arrow reaches the red zone.
Thermal operation of the ICE is critical to the safety of the geometry of parts, especially the cylinder head. Aluminum alloys, which are made of most modern units, change their structure at extreme temperatures, and the gasket gasket can burn out in minutes. The driver must be able to read indirect signs, such as loss of traction or foreign sounds, to prevent a disaster.
In this article, we will examine not only the obvious signals of the dashboard, but also the hidden symptoms that indicate that the device is not a sign of a cooling-system You'll learn to distinguish between a short-term temperature surge and a real heat stroke, and you'll learn what to do immediately after the car stops.
Primary signs of overheating on the dashboard
The first and most obvious indicator of problems is the arrow of the coolant temperature indicator, which should normally be held in the middle of the scale or in the lower sector, depending on the design of the coolant. thermostatIf you notice that the arrow started crawling up faster than usual, it's already a signal that the heat sink is broken.
But it's not always limited to the arrow. Volkswagen or BMWIf you overheat critically, you can see a text message or a flashing degree symbol on your computer display, and you can't ignore these signals, because electronics often detect a temperature surge before you can see it.
You should also pay attention to the operation of the radiator fan. If you are standing in a traffic jam, and the fan does not turn on or, conversely, it hums continuously even on a cold one, this is a sign of malfunction. cooling-systemIn the first case, the radiator doesn't blow, in the second case, the temperature sensor could have malfunctioned and transmitted incorrect data.
⚠️ Warning: If the temperature arrow has reached the red zone, immediately reduce the load on the engine. Do not turn off the engine abruptly, if there is no steam, let it work on idles so that the antifreeze circulation levelles the temperature.
Visual and sound symptoms of malfunction
When the dashboard is silent, the senses come to the rescue. heat-upMetal ringing when operating at idle speeds often indicates detonation or thermal expansion of pistons, which is a direct consequence of overheating.
You can visually detect the problem by looking under the hood after you stop, and the appearance of steam from under the radiator lid or from the joints of the pipes is a sure sign of antifreeze boiling, and it is worth sniffing, because the sweet smell of evaporating liquid indicates that the system has depressurized under pressure.
- 🔊 The appearance of clinking or ringing sounds from the depth of the cylinder block.
- 💨 Pulling the steam clubs out from under the hood after the car stops.
- 👃 A sharp sweetish smell of antifreeze in the cabin or at the open hood.
- 📉 A noticeable decrease in engine power and a sluggish reaction to the gas pedal.
Another important sign is the color change of the exhaust gases. If antifreeze enters the combustion chamber due to a breakdown of the gasket gasket (which often happens when overheating), thick white smoke will go out of the exhaust pipe, which does not disappear after warming up.
Car behaviour in motion
The vehicle's dynamic performance also changes under heat stress. When the engine overheats, the combustion efficiency of the fuel-air mixture decreases. The electronic control unit (ECU) tries to compensate for this by enriching the mixture, leading to fuel overruns and loss of traction.
This is especially noticeable when climbing a mountain or overtaking, and the car, which usually gains speed easily, begins to "sluggishly" respond to the press of the accelerator. combustion-box have an elevated temperature, which provokes premature ignition of the mixture (potassium ignition).
In some cases, especially automatic transmissions, there may be incorrect gearshifts, which is due to the fact that many modern automatic transmissions have their own cooling system tied to the engine radiator, and the general overheating affects the viscosity of the transmission oil.
When you climb uphill with full load, turn on the reduced gear, which will increase engine speed and pump speed, improving the circulation of coolant.
Critical consequences for engine components
Ignoring symptoms leads to a cascade of breakdowns, the first one is the cylinder head, and at temperatures above 120-130 degrees, the aluminum head expands faster than steel bolts, which breaks the tightness of the joint.
Then there's the deformation of the head of the block, and if the metal is "led," simply replacing the gasket won't help, it'll take expensive plane grinding or replacement of the knot. In the most severe cases, pistons get bullied when they're just welded to the cylinder walls.
Oil loses its lubricating properties when it overheats, oxidizes into tar, causing rapid wear on the crankshaft liners and camshaft. Rebuilding the engine after oil starvation is often economically inefficient.
| A symptom. | Probable cause | Risk level | Action. |
|---|---|---|---|
| The shooter in the red zone | Failure of the thermostat or pump | critical | Stop, stifle. |
| Cheap steam | Breaking of the pipe or radiator | Highly | Stop, don't open the lid. |
| Oil fogging | Antifreeze hits the crankcase | Medium. | Check the probe, drive to the station |
| Reduced traction | Detonation, cylinder overheating | Highly | Slow down, check the OG |
Algorithm of actions in the detection of overheating
If you've realized that heat-upThe first thing you need to do is to turn the stove on at maximum temperature and full power, and this will create an additional cooling circuit and help remove some of the heat from the cylinder block.
Then you have to move to the side of the road smoothly, without any sudden acceleration. Don't turn off the engine immediately if the hood doesn't bring steam down with a fountain. Let it work for 2-3 minutes at idle speeds so that the pump runs the hot liquid through the radiator.
☑️ Overheating activities
Opening the lid of the expansion tank on the hot engine is CATEGORICAL NOT. The pressure in the system can reach several atmospheres, and boiling water will instantly scald your face and hands. Wait for the engine to cool completely.
⚠️ Warning: Never pour cold water into a hot radiator! A sharp temperature drop is guaranteed to cause a crack in the cylinder block or block head, after which the engine will have to be thrown away.
Diagnostics of the cooling system
After the engine cools down, you need to make an initial diagnosis, check the level of coolant in the expansion tank, if it is not, inspect the space under the car for puddles and probe the nozzles for leaks.
Pay special attention to the state of the oil. Take out the probe and look at the color of the butter. If it has the color of coffee with milk or has an emulsion under the oil filler neck lid, then the antifreeze has entered the lubrication system. heat-up And the gasket is broken.
Why can't you put water in antifreeze?
The water reduces the freezing point of the mixture and contains salts that cause corrosion of aluminum radiators. Use only distilled water as a last resort and only to the nearest station.
It's also worth checking the electric fan, pick up the hood, start the engine and wait until it warms up to operating temperature, the fan needs to turn on automatically, and if it doesn't, the problem could be the temperature sensor, the relay, or the fan motor itself.
Timely replacement of antifreeze (every 60-90 thousand km) and checking the condition of the pipes is the best prevention of engine overheating. Old liquid loses its anti-corrosion properties and reduces heat worse.
Frequently Asked Questions (FAQ)
Can I go if the temperature light is on?
You can only drive to the nearest safe stop, and further movement with a burning overheating indicator will lead to a major overhaul of the engine in a matter of kilometers.
Why does the engine warm up in traffic but cool down on the move?
Most likely, the radiator fan or its power sensor is defective, as the oncoming air flow cools the radiator, and in traffic without a running fan, the heat sink stops.
What to do if the tube bursts on the road?
If you don't have a spare pipe at hand, you can temporarily wrap the break site with tape or tape in several layers, but this will only allow you to get to the nearest spare parts store.
How often should I change the thermostat?
The thermostat is typically 80,000 to 100,000 kilometers long, but it can fail earlier, and it is recommended to check its operation with each antifreeze replacement.