The work requires a certain temperature when the car engine is functioning, too high or too low is not conducive to the normal operation of the engine and performance play a conventional air-cooled heat generated by the engine on the other hand it is difficult to meet the demand, so widely used in the water-cooled automobile engine thermal design. The role of the cooling system is to keep the engine in the most favorable temperature range to increase engine power, reduce engine wear and fuel consumption. Temperature is too high or too low will adversely affect the engine work.
How much antifreeze temperature normal?
To ensure the engine is operating at normal temperature range cars will be equipped with an engine coolant temperature sensor, usually shown separately on the car dashboard (water table), if the antifreeze temperature alarm will occur. Generally the engine coolant temperature gauge uses a physical or virtual dial pointer display, and a few vehicles no dashboard warning signs appear only when the temperature is too high. Whether it is physical or virtual water table, which is similar to the basic orientation of the pointer, usually with 60 ℃ --120 ℃ dial or Cold (C) - Hot (H) logo. Unlike conventional antifreeze water, add calcium chloride, organic methanol, ethanol, ethylene glycol, glycerin and other components so that it can work at a temperature above 100 ℃.
From the above description we know that the engine coolant temperature is not as low as possible, not better, to be within a certain range, the normal temperature is the center of the pointer 90 ℃. One antifreeze temperature rises rapidly after vehicle start, after the pointer reaches the central position, the heat exchange balance antifreeze temperature does not rise, the best start when the temperature reaches the intermediate position in general, which is why the car before the vehicle starts to heat the reasons .
The temperature of the water table is too high failure analysis:
General Cooling system failure is mainly contained leakage, insufficient coolant, cooling fan failure, circulation pump failure.
1, leakage, insufficient coolant
After the leak can lead to insufficient cooling system antifreeze, which led to antifreeze temperature, and if found low antifreeze should first check whether the leak, if there is no time to add to the same type of antifreeze, do not add water or other models antifreeze, so as not to cause dilution or precipitation, resulting in failure or malfunction.
2, cooling fan failure
Cooling fan failure will result in heat transfer to the antifreeze and the lack of timely high heat when the car engine running speed, resulting in antifreeze temperature, which led to "boil" and other issues, in traffic on the way must pay attention to the temperature of antifreeze , first reduce the speed when abnormal stop, but do not turn off Check the cooling fan, circulating pumps if there is a fault.
Cooling fan failure include two categories: total turn and stopped, generally do not turn more.
Do not turn the easiest is to first check the insurance, if the insurance use the meter to measure the burn line, see the problem is not short-circuited, causing burn insurance, then check the temperature control switch thermostat switch is working properly, the predetermined temperature is energized, if temperature control switch normally give direct electrical electronic fan, to see whether the operation.
Always turn first to check whether the lack of antifreeze tank caused by high temperatures, lack of antifreeze to check if there is no leakage of place: pumps, piping. Check whether the oil in the water, the spark plug combustion conditions, but also to determine whether there is antifreeze leak into the cylinder, check the water circulation system has led to local air circulation there. Then see if dirty water tank surface, resulting in poor heat dissipation. Whether there is water inside the tank as a result of poor circulation alkali oxides, the final inspection is not bad thermostat switch has been energized.
3, circulating pump failure
After the water pump fails, the engine thermal water side is not timely circulation, leading to the engine water temperature will start rising rapidly, cooling system failure, the water temperature alarm, and accompanied by "boil" and so on. If found early and take appropriate measures to avoid further failures will pull tanks and other losses caused due to poor cooling; it must be found when the water temperature is too high, warning lights, "boil" and other phenomena, stop and check the fault as soon as possible causes, help repair station to resolve when necessary.
Pump failure is mainly divided into two categories: Hugging and impeller bearing damage.
Hugging the bearing less, once this happens, ranging from the timing belt damage, while the engine valve piston is benders. And pump bearings are mostly maintenance-free bearings, will appear before locking occurs because abnormal sound or wear bearing partial cause water pump leakage.
Therefore, when the daily inspection or routine maintenance checks to pay attention to the water pump, timing belt replacement and other related parts when the pump should also be checked. When there is abnormal sound near the pump to pay attention, not to drive belt slippage voices mistaken for the sound of the pump.
Common forms of damage impeller impeller cracking, loose from the impeller or impeller shaft corrosion, corrosion impeller usually does not cause engine failure. Impeller cracking or loose from the impeller shaft, the coolant circulation slows down, prone to overheating of the engine failure. Damaged impeller rotation are also likely to hit the water pump housing, causing the housing fragmentation.
Impeller causes of damage is usually due to engine appeared in the case of abnormally high temperature, and some because of the quality of the water pump impeller. Check the impeller for damage, after most of the water pump impeller can be removed to see the situation, some of the engine after removing the thermostat can touch the water pump impeller.