Things To Know About Your Car’s Temperature Gauge

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The water temperature gauge in a car is also an important component in maintaining normal engine temperature.

Many drivers may pay attention to the gasometer, tachometer, and speedometer, but not the water temperature gauge.

However, if the water temperature gauge is not checked on a regular basis to ensure that the coolant is at the normal temperature, the engine can be left running hot, resulting in problems such as overheating and engine seizure.

Therefore, this article explains the role of a car’s water temperature gauge, what to do and what to look out for when the water temperature gauge shows an abnormality and the reasons and procedures for adding an additional water temperature gauge.

Since engines are prone to high temperatures in the coming season, it is important to understand the importance of water temperature gauges so that you can take action when the need arises.

What Is A Car Water Temperature Gauge?

A car’s water temperature gauge is an important part of maintaining the engine at the proper temperature. In water-cooled cars, coolant circulates around the engine to cool it.

The car water temperature gauge is a part that measures the temperature of that coolant. The standard water temperature gauge installed in a car does not display the temperature in detail but is a simple type that displays H for high coolant temperature and C for low coolant temperature.

The temperature of the coolant used to cool the engine is very important to prevent engine failure, and the proper temperature varies from car model to car model but is approximately 70 to 95 degrees Celsius. If the coolant cannot be kept at the proper temperature, the engine is more likely to overheat and malfunction.

Therefore, water temperature gauges are installed to properly control the temperature to prevent the engine from overheating.

In addition, if the water temperature becomes excessively high or low, a warning light on the instrument panel in the driver’s seat will come on.

In other words, it is an important component that sends a sign to the driver before a serious malfunction occurs due to water temperature effects.

Relationship Between Water Temperature Gauge And Coolant

There is a close relationship between the water temperature gauge and the coolant.

Coolant is circulated around the engine to remove heat from the engine, but if the coolant cannot absorb the heat and the temperature of the coolant rises, the water temperature gauge warning light and other warning signs indicate an abnormality.

There are several causes for the warning light to come on, but basically, problems related to the coolant are very common.

For example, if the coolant does not meet the standard amount, not only will it not be able to absorb the heat from the engine, but the temperature on the water temperature gauge may not be displayed accurately, which may cause problems such as component failure.

In addition, if the radiator used to circulate the cooling water fails and malfunctions, it will not be able to circulate the cooling water to cool the engine, leading to serious problems such as overheating.

Thus, since there is a close relationship between the water temperature gauge and the cooling water, it is important to note that if either of them is not working properly, such as a water temperature gauge failure or lack of cooling water, it will lead to serious engine problems.

To avoid serious problems, please check the reservoir tank under the hood on a daily basis to see if the coolant is sufficient to the specified level.

What Happens When The Water Temperature Gauge Exceeds 100 Degrees?

Although the water temperature gauge does not indicate a specific temperature, when the water temperature gauge points to H, the temperature of the coolant is said to be 120 degrees.

What happens if the water temperature gauge points to “H” while the car is running and the coolant temperature exceeds 100 degrees Celsius?

The boiling point of the coolant circulating in a car to cool the engine is approximately 120 to 130 degrees Celsius, depending on the type of coolant.
In other words, when the water temperature gauge reads “H,” the water has reached the boiling point.

Even if the water temperature has not reached the boiling point, if the temperature of the coolant exceeds 100°C, bubbles will form in the coolant, which will not be able to absorb the heat from the engine, causing it to overheat.

If overheating occurs, not only will the water temperature gauge show abnormalities, but also strange noises and odors may occur, and steam may be generated from the hood.

Furthermore, if the condition is not addressed, the engine can seize up and destroy the engine itself.

Basically, if the water temperature gauge is in good condition, the needle of the water temperature gauge will always point to “H” or the warning light will come on, so take action before it becomes a serious engine problem.

What To Do And What To Do When The Water Temperature Gauge Warning Light Comes On

If the water temperature gauge warning light comes on, it is possible that the coolant is not absorbing the heat from the engine properly and the engine is running hot.

If this is the case, the engine may fail and expensive repairs may result if the problem is not addressed immediately.

However, if the warning light comes on and is properly addressed, there is a possibility that damage to the engine can be reduced.

Therefore, the following is an explanation of what to do and what to be careful of when the water temperature gauge warning light comes on.

Stop The Car Immediately And Allow The Engine To Cool Down

If the water temperature gauge warning light comes on, stop the car immediately and concentrate on cooling the engine. However, be aware that if you immediately turn off the engine, the coolant circulation will be stopped and the engine will become even hotter, possibly causing it to seize.

When the warning light comes on, the first park the car in the shade as much as possible and let it cool down while opening the hood. Opening the hood is effective in cooling the engine because the outside air directly hits the engine.

Before opening the hood, however, be sure to check for the presence of water vapor. If you open the hood while water vapor is present, it is very dangerous because of the high temperature.

Also, if you have water, you can cool the radiator by pouring water directly on it.

If you do pour water on the radiator to cool it down, be careful not to pour water directly on the engine. If you suddenly pour cold water on the engine, it will cool the thermal expansion at once and cause cracks to appear.

Finally, never open the radiator cap when the water temperature is high. Opening the cap will cause water vapor inside the radiator to blow up.

After Taking First Aid Measures, Request An Inspection

If the water temperature gauge warning light comes on while driving, perform the above procedures, but what you do afterward is also very important.

If the water temperature rises, it is not a temporary problem; there may be something wrong with the radiator-related parts or the coolant.

Therefore, even if the water temperature temporarily drops, be sure to have it checked by a dealer or a maintenance shop.

Even if the temperature can be temporarily lowered, if the vehicle is driven as is, the warning light may come on again and the engine may overheat. Furthermore, if the engine continues to run at high temperatures, not only will it lead to serious engine failure, but it may also emit black smoke and catch fire.

In such a situation, not only would the risk of secondary damage increase, but the car would not even be repairable and would have to be replaced.

If the warning light comes on and the temperature drops, do not drive the car immediately, but take first aid measures and have the car inspected by a dealer or mechanic as soon as possible.

Dangerous If You Do Not Notice The Warning Light On The Water Temperature Gauge

Since the water temperature gauge is an instrument that indicates the temperature of the cooling water that absorbs heat from the engine, failure to notice the warning light can cause a variety of problems.

For example, if the needle of the water temperature gauge keeps pointing to “H” and the warning light is on but the driver does not notice it, not only will the engine overheat, but the engine will tend to seize up and the repair cost will be high. If the engine seizes up, it can cost more than 1 million yen to repair, depending on the model of the car.

Furthermore, in the worst-case scenario, the engine will emit black smoke and may be beyond repair.

Another condition called overcooling occurs when the engine is too cold.

Be careful if the water temperature gauge needle does not rise from C even when the car is running.

If overcooling occurs, the machine will control the water temperature to raise it faster, increasing the concentration of fuel and possibly damaging the plugs.

Furthermore, if the engine temperature is low, the oil pressure in the engine oil will not rise, which is dangerous because it can cause problems with the pistons and cylinders inside the engine.

Additional Water Temperature Gauge In Car To Control Temperature

Basically, the water temperature gauge that comes standard on cars is a simple instrument that only goes up and down between H and C. Therefore, it is impossible to know what the actual temperature of the coolant is.

In these cases, an additional water temperature gauge can be installed to accurately control the temperature. Knowing the exact temperature will prevent engine problems such as overheating.

Below we will explain the reasons for installing an additional water temperature gauge, the procedure, and its cost.

Reasons To Install An Additional Water Temperature Gauge

For cars with engines running at high RPM, such as sports cars, the water temperature tends to rise easily, so it is recommended to know the exact temperature and control the temperature.

In addition, older cars, such as vintage cars, are not equipped with a water cooling system, so a water cooling system may be installed later. In such cases, an additional water temperature gauge is also required.

Although an additional water temperature gauge is not always necessary, you may want to install an additional water temperature gauge depending on the type of car and the situation.

Procedure For Installing A Water Temperature Gauge

The installation of an additional water temperature gauge is a relatively easy part of the process, but it is difficult for amateurs, so if you are unsure about the installation, please consult a mechanic or professional. The installation procedure for the water temperature gauge is as follows.

  1. install the water temperature sensor on the adapter
  2. remove the coolant tank
  3. cut the radiator hose and interrupt the adapter
  4. connect the wires to the water temperature gauge through the wiring
  5. install the coolant tank
  6. refill the coolant tank
  7. bleed the coolant

This completes the installation of the water temperature gauge. Be sure to bleed the air out of the coolant tank after installation.

If air remains in the coolant, the coolant will not be able to absorb heat from the engine properly. This is not a difficult task, but be aware that the procedure varies depending on the car model.

Also, some car models can read the water temperature sensor signal from the ECU (engine control unit) that controls the engine operation, so check before purchasing.

Cost Of Adding A Water Temperature Gauge

When adding a water temperature gauge, the cost of parts will range from 40$ to 200$.

If you ask a dealer or maintenance shop to install a water temperature gauge, the labor cost will be 100$ to 200$, so the total cost will be 400$ to 500$.

Please note that if you ask the dealer or maintenance shop to add a water temperature gauge, they may also charge you for coolant parts and replacement labor.

If you want to save on labor charges, we recommend that you install it yourself. The work itself is not difficult, so if you are not worried about maintenance, try installing it yourself.

Also, recently there are products on the market that allow you to install additional meters such as a water temperature gauge, tachometer, and turbo gauge simply by attaching them to the car’s diagnostic monitoring connector, so it may be a good idea to install those.

However, easily installable meters are limited to compatible car models, so you need to make sure that your car is compatible with that meter.

Conclusion

In this article, we have explained the role of the water temperature gauge in a car, what to do and what to look out for when it shows an abnormality and the reasons and procedures for adding an additional water temperature gauge.

A car’s water temperature gauge is an important component needed to determine the temperature of the coolant circulating to cool the engine. As such, it serves to send us signs before serious engine problems occur.

The standard water temperature gauge is a simple H and C display, but it is also an essential instrument to determine if the engine is in good condition.

If the engine becomes too hot and dangerous, it will turn on a warning light and send a sign to the driver, preventing serious engine failure before it occurs.

If the warning light on the water temperature gauge comes on, the driver should concentrate on cooling the engine and then have it serviced at a dealer or mechanic’s shop.

If this should lead to a serious breakdown, it will result in expensive repairs. To avoid such a situation, please consider installing an additional water temperature gauge as a means of accurately measuring the temperature.