In this article, we explore the role of the engine coolant thermostat and its simple but necessary mechanism. In addition, we provide you with easy methods to check thermostat car issues and ensure your cooling system is working efficiently.

Engine coolant thermostat: What is it and how does it work?

The engine thermostat might be a simple and small device but plays an oversized role as a crucial component of a vehicle’s cooling system. Its main job is to control the coolant flow towards the radiator, deciding when and how the heat is added, increasing engine combustion efficiency, and reducing emissions.

Keep learning: Car temperature: Key aspect in a vehicle’s performance

A traditional thermostat contains a wax that’s compounded to melt at a certain temperature. As the engine temperature rises, the wax melts and expands causing the thermostat to open and coolant to flow. When the engine temperature drops, the wax cools and contracts, causing the valve to close. Engine thermostats have a temperature rating at which they open or close, this rating differs from vehicle to vehicle.

However, modern systems use a map controlled engine cooling thermostat, which allows for more precise control over the engine’s temperature. This system adapts to various engine conditions, improving efficiency and performance by controlling the coolant flow based on the engine’s operating map.

How to test thermostat car

There are several ways to check the health of your car’s thermostat and you don’t necessarily have to remove it: observing the coolant flow or measuring the temperature of the upper and lower radiator hoses with an infrared thermometer.

Here’s how to check thermostat car performance effectively:

1. Check if the thermostat is stuck closed.

Watch the flow of coolant through your radiator. If the hose is cool, there would be no flow even after the engine reached the operating temperature, and the lower radiator hose would remain cool. It’s probably a sign that you have a stuck closed thermostat that needs replacement.

Watch the flow of coolant through your radiator. If the hose is cool, there would be no flow even after the engine reached the operating temperature of engine, and the lower radiator hose would remain cool. It’s probably a sign that you have a stuck closed thermostat that needs replacement.

Article of interest: 5 thermostat failure symptoms and how to avoid them

2. Check if the thermostat is stuck open.

The most basic test you can do is to start the engine on your car and allow it to idle for 10-20 minutes to reach its optimal running temperature. After several minutes, you will see that the temperature goes high while the engine is operating. The first thing to do is to examine the radiator hose. If the thermostat is stuck open, the lower radiator hose will start warming up as soon as the engine is started.

3. Valve’s test: testing by heating in hot water.

A quick and easy way to check the thermostat is also to remove it from the engine and test it by heating in hot water. This is one of the most accurate methods to test thermostat car performance.

First off, with the help of a thermometer, heat water until it is at least twenty degrees above the open temperature of the thermostat. Then, get the thermostat and drop it in the pot of hot water (make sure it’s deep enough to cover the whole thermostat) and carefully lower it into the water and observe it: at the temperature marked on the thermostat, it should quickly open the unit. If it does not fully open, it is stuck.

Recommended for you: Thermostat: discover its key elements

Is your thermostat stuck?

The main problems a thermostat can experience are being stuck in an open or closed position. In any case, the thermostat replacement should be carried out with a new one if it’s faulty.

• A thermostat that is stuck open: If it’s stuck open, it’s definitely going to cause some problems for you. In this scenario, the flow of coolant will be unrestricted throughout your engine and the engine warms up with difficulties. In this case, you’ll notice a significant performance drop, low power and torque.

• A thermostat that is stuck closed: If the thermostat is stuck closed, coolant flow is disrupted and coolant cannot get through the radiator causing the engine to overheat, which also influences fuel consumption. This can lead also to the damage to cylinder-head gaskets.

Dolz thermostats: Proven reliability and premium qualit

All Dolz thermostats are integrated thermostats that adjust the flow of coolant towards the radiator, deciding when and how heat is added and are designed according to OE specifications:

• Proven reliability. 100% tested.
• Premium quality. ISO 9001:2015 Quality management system.
• Optimal design for maximum efficiency.

So, if you experience that your car overheats soon after starting it, or the dashboard’s temperature gauge goes below normal, make sure to get your thermostat replaced.

For further information on any reference, receive commercial information or technical product specifications (including assembly notes), contact us! Keep your vehicle running smoothly by staying ahead of potential cooling system issues!

La entrada Understanding and testing the engine coolant thermostat se publicó primero en Industrias Dolz.

This is especially true during summer season: although most modern vehicles will run smoothly even during extremely hot conditions, the proper cooling system maintenance can eliminate unnecessary risks.

Let’s take a look at what cooling system maintenance means and how to guarantee the cirtcuit doesn’t present any issues.

How does hot weather affect your car?

Warm weather can have significant effects on a car’s correct operations, as it influences multiple systems including the battery, tires, motor oil and body shell.

When it comes to the cooling system, the issues that can arise from warm weather are multiple. While cooling systems often remain neglected in winter, they can cause issues when the warm temperatures arrive, as they’re expected to increase their operations.

The cooling system is in charge of guaranteeing an engine doesn’t get too hot, as a typical combustion engine will run more efficiently at around 200 degrees Fahrenheit or 93 degrees Celsius. At higher temperatures, metal parts will experience issues (they may even melt or fuse together) which turns into a variety of issues. 

A cooling system that works well will eliminate these risks. However, if the cooling system is defective, it may not be able to do so at warm temperatures, causing the vehicle to overheat because of the lack of air flow across the engines.

You may like: Dolz technical video: The water pump in the engine cooling system

How does the cooling system work?

How does the cooling system work in a car? The cooling system is a closed circuit responsible for managing the engine temperature, circulating the coolant (or antifreeze) that will be responsible for dissipating heat from all engine areas subject to thermal stress.

While engines rely on internal combustion to propel vehicles, the cooling system uses a closed circular process to guarantee overheating is avoided and constant temperature levels are kept.

It works by constantly passing fluid through channels in the engine block. The coolant, driven by the water pump, is pushed through the cylinder block. As the solution passes through these channels, it absorbs heat from the engine. Usually the pump sends coolant up through the engine and down through the radiator, taking advantage of the fact that hot water expands, becomes lighter and rises above cool water when heated.

Cooling systems include the following components: 

• Coolant.
• Water pump and hoses.
• Thermostats.
• Fans.
• Radiator.

Problems in these may include cracked hoses, leaks, loose or missing radiator caps. Additionally, these are some common signs of issues relating to the cooling system:

• Engine overheating.
• Antifreeze leaks under the vehicle’s front.
• Increase in temperature (due to the lubrication oil not to fulfill its function).
• Smell of antifreeze or coolant (due to evaporation) and high fuel consumption.

Cooling system maintenance tips

• Check for coolant levels often, especially if you see coolant under the car after it’s been parked for a while, as this might be a sign of cooling circuit problems.
• Add new coolant every two years. In order to do so, flush the radiator. If it’s done during the warm season, add a 50/50 mixture of antifreeze and water. If coolant is rusty or discolored, it might be a sign of corrosion.
• Check the condition of components such as the radiator, the fan and especially the water pump, heart of the cooling system, and replace them when necessary. In addition, it should be remembered that it is important not to overlook the timing belt, because if it breaks down it will cause the water pump to fail, which can cause serious damage to the engine.
• Perform a complete cooling system bleed, this will remove debris and air from the system, helping it to function properly and without temperature management issues. In order to do so, choose the correct purge equipment so that an optimal circuit cleaning can take place, including the main radiator and the heating radiator, both with the engine working and when the engine is stopped.

Keep reading: How to detect cooling circuit problems

An optimal cooling system, easier with quality spare parts

As specialists in vehicle cooling, at Industrias Dolz we know the fundamental role that this system performs in the car, as well as the importance of choosing components of the highest quality when replace them.

Quality has different nuances depending on the perspective from which it is analyzed, but without a doubt, choosing parts that are OE equivalent in terms of quality standards will ensure that their manufacture processes are efficient and continually improving for the highest performance.

With almost 90 years of history, we are one of the European leaders in the manufacture of water pumps, completing our product offer with timing belt kits, timing chain kits and thermostats for the aftermarket industry.

Want to learn more about cooling system maintenance and how the right vehicle components can make sure your vehicle’s life cycle is extended and your engine runs smoothly? Get in touch with us and see how our cooling system components can help you.

La entrada Why should you perform cooling system maintenance before the summer season? se publicó primero en Industrias Dolz.

La entrada The importance of an automotive thermostat in a car’s cooling system se publicó primero en Industrias Dolz.

La entrada Engine cooling system: how it works and main components se publicó primero en Industrias Dolz.

In today’s article we explore the effects of pump impeller cavitation, and we also talk about the preventive measures that must be taken against this phenomenon and keep water pump in safe working condition.

The impact pump impeller cavitation

Pump impellers can tolerate a small amount of low energy cavitation without damage or significant reduction in life. The more intense the cavitation is, the quicker the water pump will be damaged.

In other words, cavitation causes pump performance deterioration, mechanical damage and erosion to the impeller as we can see in the following pictures (which can ultimately lead to pump failure).

The impeller is one of the key components of a water pump, essential for its efficiency and performance within the cooling circuit. But what is impeller in pump? The impeller is the rotating component responsible for moving coolant efficiently through the system, ensuring optimal engine temperature and preventing overheating.

Keep reading: The importance of the water pump impeller

There is also the possibility of material release from the blades and even from the volute as well.

Under normal conditions, the impeller of a water pump do not show any deterioration and can only be encrusted with settled solids build-up on their blades.

Are there any signs of failure on the vehicle?

The answer is Yes, but we must address a few explanations first to understand what cavitation is and how it affects the operation of the cooling system.

The first issue to highlight is that any liquid and in general any material can exist in liquid, solid or gaseous state. In this case, the coolant state basically will depend on two parameters: pressure and temperature (during a phase-change process, both are dependent properties).

By decreasing the pressure of the coolant liquid to the same temperature, the liquid will turn into a vapor state. And vice versa, if we increase the pressure of a gas, it will become a solid.

The coolant circulates throughout the engine coolant circuit. This is a closed-loop and sealed system by the radiator cap or the expansion tank cap.

When we start the vehicle’s engine, the heat from the turbocharger and the engine cylinder head heats up the coolant and thus the pressure in the circuit increases. At that moment, two situations can occur:

1. If the pressure of 1.0 bar is exceeded, the circuit pressure is relieved by opening momentarily.
2. If the cap does not close the cooling circuit, the pressure automatically decreases (being atmospheric).

How is cavitation done?

Cavitation in the water pump happens in two phases. Initially, the coolant exposed to high temperatures begins to evaporate and forms the bubbles that constantly burst into the coolant that circulates through the water pump.

The process that initiates cavitation is a sudden pressure drop and/or coolant temperature increase, that is: rapid changes in pressure. This occurs when the coolant liquid passes from the suction side of the impeller, and the pressure decreases, the liquid molecules turn to vapor. But when the impeller increases the speed and transfers the energy of that vapor, this vapor becomes coolant liquid again. Ejecting (in an explosive way) bubbles that collapse, creating an intense shockwave that hits the impeller and creates pump vibration and mechanical damage as we have observed previously.

How to prevent pump cavitation?

By preventing cavitation, you will significantly increase the efficiency and lifespan of your water pump. Among the main causes of cavitation in cooling systems is the incorrect use of coolant.

To avoid it, it is important to maintain the appropriate coolant fluid level, as well as always use the coolant fluid recommended by the car manufacturer. It is also important to inspect the condition of the water pump or thermostat through preventative maintenance.

Related content: Coolant guide. Suitable coolants for the vehicle.

At Dolz we also recommend that, if you see the impeller has material loosening, do not replace just the water pump, replace also the radiator cap or the expansion tank cap in the same operation.

In conclusion, good design to avoid cavitation is always the best option. Dolz water pumps have excellent certified quality, equivalent to the original equipment manufacturers. Our commitment to Quality, Service and Innovation has been amply demonstrated for decades, been recognized as one of the leaders in the manufacture of water pumps in Europe.

If you need any help identifying which components you need for your system or further information about Dolz’s water pumps for passenger cars, heavy duty or commercial vehicles, don’t hesitate to contact us at dolz@idolz.com.

Don’t compromise on quality!

La entrada An overview to pump impeller cavitation se publicó primero en Industrias Dolz.

In this article we review some basic maintenance operations that will help the operating life of your engine and keeping it cool during the summer months.

The antifreeze in summer, a key factor

The combustion engines in our vehicles give off a lot of heat during operation and require a specific liquid for its thermal control. As the name suggests, the main function of the coolant/antifreeze is to transfer heat from the vehicle’s coolant flowing through it to the outside, preventing and reducing evaporation. This will make it easier for the engine to work at the optimal temperature, avoiding overheating, malfuctions and helping to protect it from corrosion.

In addition, as a good ally of the engine, thanks to its constant flow it also acts as a double lubricant in the cooling system.

For all these reasons, it is one of the liquids that, together with the engine oil, cannot fail in your vehicle.

It is important to remember that engine coolant does deteriorate over time. So, if this liquid loses its properties, there is the risk of damaging elements of the system as the water pump. Additionally, your engine temperature will raise and things can get troublesome pretty quickly.

How to check the coolant level?

Although the cooling system is a closed-circuit and sealed. This is subjected to alternate cooling and heating without air contact generating that a minute amount of coolant might evaporate. If the coolant falls below the safe level the water pump won’t work properly and therefore the cooling circuit would not be able to manage the engine temperature. Which is why you should keep an eye on the antifreeze in summer.

The level can be checked by looking at the minimum and maximum marks on the side of the expansion tank. As a rule, the expansion tank is a semi-transparent plastic and often has a closing cap with a warning symbol regarding the danger of remove the cap when the engine is on, or the cooling system is hot.

How to top up the antifreeze

To fill the antifreezy we will use as references the two maximum and minimum marks on the side of the tank. Let’s show you how to do it safely and correctly:

• First of all, you need to know what type of antifreeze to use in your vehicle. There are different additive technologies depending on each application: organic, inorganic and combinations of both (hybrids). For this, check your vehicle owner manual.
• Make sure that the engine is cold with the engine stopped, otherwise part of the liquid may continue in the circuit and distort the level.
• Check the coolant level.
• Make sure you use a rag or protective gloves when unscrewing the reservoir cap.
• Fill the reservoir to the recommended line. Once you see the liquid reach the maximum line, screw the cap back on until you hear it click – and you’re done. (Please remember not to exceed the marked line, otherwise it may cause damage to the system.)

You should now be ready to go.

Coolant Guide: Choose the right engine coolant

How long does antifreeze last in a car?

At this point you will be wondering when it is necessary to refill your car’s coolant.

Beyond the hot summer months, by proactively maintaining the cooling system, drivers can ensure their safety, the good condition of all the components and reduce the likelihood of unexpected breakdowns. For this reason, at Industrias Dolz we always recommend a preventive maintenance if you want to increase the useful life of your vehicle. To do this, it is convenient to check the liquid level periodically, replacing it every two years or 40,000 miles – whichever occurs first.

As specialists in vehicle cooling, at Industrias Dolz we know the fundamental role that this system performs in the car, as well as the importance of choosing components of the highest quality when replace them.

Quality has different nuances depending on the perspective from which it is analyzed, but without a doubt, choosing parts that are OE equivalent in terms of quality standards will ensure that their manufacture processes are efficient and continually improving for the highest performance.

With almost 90 years of history, we are one of the European leaders in the manufacture of water pumps, completing our product offer with distribution kits and thermostats for the aftermarket industry.

Want to learn more about cooling system maintenance and how the right vehicle components can make sure your vehicle’s life cycle is extended and your engine runs smoothly? Get in touch with us and see how our cooling system components can help you.

La entrada Why check the antifreeze of the car in summer se publicó primero en Industrias Dolz.

What exactly is a cooling circuit?

A cooling circuit is a vehicle’s mechanism designed to keep all thermally-stressed areas of the engine from being damaged. The internal combustion necessary for powering vehicles produces substantial heat, and the coolant circulating in the cooling circuit dissipates this heat to ensure a constant engine temperature level in the engine.

The main function of a cooling circuit is to ensure that the engine runs at its optimal operating temperature. While extreme high temperatures can cause overheating, seize, and cracked engine blocks, a cold engine can result in worn out components, more pollutant emitted and a less efficient engine.

Cooling circuit components

The cooling circuit’s main core component is the water pump; in charge of activating the circulation of the coolant through the entire circuit. Other key components include the radiator; in charge of transferring the heat from the fluid inside to the air outside, and the thermostat; which ensures that the liquid is at the right temperature by blocking or opening the passage.

Together with the previously mentioned elements, other components such as freeze plugs, cooling fans, head gaskets, hoses and an overflow tank amongst many others, all add up to keeping the temperature within standards of safety and efficiently.

Related content: Engine cooling system: how it works and main components

Cooling system: main problems

Cooling systems fail more often than any other mechanical system, usually related to poor maintenance and neglect, or in relation to external wear causes. The following are some of the main causes of cooling system problems.

Poor use of liquid coolant

Cooling system designers have formulated complex mixtures of water and waterless mixtures with various additives that reduce the freezing point of coolants and prevent corrosion of the metals involved. 

However, specific coolants are suitable for different vehicle models and misdoings such as not using the coolant mixture specified in the vehicle’s manual and/or low coolant levels will negatively affect the water pump and engine temperature.

Failures in auxiliary equipment

Another of the most common cooling circuit problems involves failures in auxiliary equipment. The misfunctioning of closely involved components such as the thermostat or the radiator cooling fan will destabilize engine temperature. 

The thermostat, for instance, helps an engine identify when it needs to cool down. But if it is failing to work properly, the engine will continue to get hotter and hotter until the damage is irreversible. Another example is the radiator cooling fan; if this component breaks down, heat will not be able to dissipate from the coolant, and this will result in overheating and potential engine damage. 

Pressure drops

When pressure within the system drops or is not evenly distributed throughout the cooling circuit, vibration is subject to cavitation (vapor formation). 

If this happens while the engine remains under load, metal temperature will spike and the hot spots will cause important issues such as pump flow interruption, erosion damage, poor engine efficiency, detonation, power loss and full-blown overheating.

Diagnosis related to the car cooling.

This post addresses some of the most common cooling circuit issues, while providing insights into how to address and prevent these. A poor or incorrect use of liquid coolant is one of the main issues causing cooling circuit problems. 

Loss of liquid coolant due to leakage

Even though leaks in the cooling system can be easy ailments to diagnose, they are certainly harder to locate. Signals of a coolant leak include the temperature gauge pointing towards the red zone, steam coming from under the hood or the engine facing a sudden stall.

There are three main causes for coolant leaks: external leaks, radiator cap leaks and internal leaks. Whereas external leaks can be noted by basic inspection, internal leaks are usually caused by faulty components. Whichever the case, identifying, sealing and repairing involved components is a must, and cleaning any resulting contamination should come with it.

Overheating

Probably the most common symptom of a cooling system failure, overheating of vehicle’s internal parts can result in a variety of distressing effects; from burned valves, to damage of the cylinder head gasket and engine seizure. 

It is usually caused by an insufficient quantity of liquid in the circuit, but the truth is that the causes for overheating can be multiple. What is most important is the fact that any indication of overheating will deteriorate a vehicle, so shutting down the engine and fixing the problem is the best practice to prevent further damage.

Frozen coolant and overcooling

If the engine and other inner vehicle parts are running below the normal operating range, the engine will lack achieving full; consuming more fuel and therefore meaning more pollution. This matter will also increase cylinder and other component wear due to the increased amount of fluid friction loss. 

This is usually due to extreme temperatures affecting the coolant temperature, especially when the thermostat opens too soon or the valve remains open for too long. If the vehicle stands still for a long time where the ambience temperature is below the freezing point, the coolant may freeze completely and may cause serious breakage to any part of the system.

Incorrect temperature gauge reading

Sometimes, it is not the actual cooling system what is failing, but the temperature reading. When the engine is functioning, and the coolant is doing its job, the temperature gauge needle should be somewhere in the middle between the hot and cold indicators.

Temperature sensors can also fail, so if the indicator fitted on the instrument panel is signaling tricky readings, a thorough check should be carried out to measure real cooling temperature and contrast it with the reading of the gauge.

Keep reading: The importance of using the right coolant liquid

Other factors and concerns to consider

While the list of causes, signals and issues related to cooling circuit problems might seem never-ending, the truth is that with correct observation and preventive maintenance, the cooling circuit can have a long operating life.

It is a matter of attention, care and common sense. For instance, sudden noises in the cooling system are an evident signal that something goes wrong, and the same happens with most of the factors listed above. 

With regard to the correct use of coolant, a simple look into the cooling circuit will let you know whether it has been maintained correctly. By looking inside the expansion tank, the pipes, and the water pump, you can look out for clear signals such as the appearance of solid residues, yellowish and reddish coloring, white spots and incrustations, as just a few examples, that indicate the use of an unsuitable coolant.

Dolz, leader in the manufacture of water pumps for the aftermarket.

In addition to the water pumps, it also has a wide range of thermostats, thus completing its range of cooling products for the vehicle.

Contact us to learn more about our range of water pumps and products!

La entrada How to detect cooling circuit problems se publicó primero en Industrias Dolz.

To prevent vehicle engines from overheating, cars and trucks with internal combustion engines incorporate a key player cooling system where circulates coolant from the radiator to the vehicle’s engine block. But what exact role does the coolant liquid play in this cycle?

So what is coolant liquid role exactly regarding the water pump?

The coolant liquid, also known as antifreeze, is the fluid that flows through a vehicle’s engine to keep temperature at its optimal point. It is a blend of water and antifreeze that prevents the radiator from freezing when extreme cold and from overheating when extreme heat. 

Coolant liquid is the best form of engine cooling due to the fact that water transfers heat way more efficiently and quieter than air. However, there are many different coolants circulating around, each of them with different characteristics and formulas. 

Choosing the right engine coolant and avoiding the mixture of two different types will ensure best practices for a vehicle’s cooling system performance.

In areas where liquid circulates at an elevated speed and pressure fluctuations are hefty, the coolant’s inhibitors are in charge of protecting the engine against corrosion and damage. Thus, only the right coolant will fulfil its temperature-regulating mission.

Keep Reading: 10 reasons to choose Dolz products for your automobile spare parts

Main consequences of using unsuitable coolants

Coolants are specifically formulated to keep its designated engine type properly running in extreme temperatures. The use of unsuitable coolant liquids may result in the following complications:

• Solid, corrosive deposits and residues that can generate clogging.
• Origination of suspension solids caused by agitation of the water pump’s flow; leading to abrasive wear and causing leaks.
• Eventual damage of vehicle components, not only to the engine but to other core parts such as the water pump, radiator hoses or cylinder head gasket.
• Ultimate overheating and failure of the water pump, essential for vehicle functioning and performance.

How to choose the right type of engine coolant

A suitable coolant will be determined not only by the type of vehicle, also the climate and region where the vehicle is to be driven. The proportion of water and antifreeze, for instance, is usually a fifty-fifty mix, although in extremely cold weather conditions, the optimal percentage of antifreeze may rise to around sixty-five percent.

Engines are made of different materials, such as aluminium alloy or cast iron, which is why different coolants work best with particular engines. So, a key point to a safe choice is using the kind recommended by your vehicle manufacturer; every individual engine type has its specific needs. 

Choosing the right coolant also requires considering its condition. Coolants have expiry dates, while they tend to deteriorate, so do not think of re-using the same water-based solution and make sure to refill the cooling system with a new coolant. 

Last but not least, NEVER try mixing coolants either, because there is the probability that they will counteract each other.

Dolz’s recommended purging machine for optimal cleaning of the cooling system

There is no longer need for you to worry about spending vast amounts of time in exhaustively cleaning vehicles’ cooling system. Dolz’s nearly 90 years-experience as a water pump manufacturer have served to present the best practices for its maintenance.

Micrauto’s high-end technology machines eliminate at least 90% of residues in only 20-45 minutes, depending on each case. A highly efficient purging system that eradicates from iron oxide, to aluminium oxide, to oil residues.

La entrada The importance of using the right coolant liquid se publicó primero en Industrias Dolz.