Each driver has their own considerations as to which powertrain is actually better. Some believe that the small volume brings a big advantage and provides fuel economy. Others believe that it is worth buying only a gasoline engine because of its simplicity and versatility. Still others choose only voluminous diesels with a turbine for immense pleasure from excellent traction. Let's take a look at how to operate a diesel power unit, which has a number of features of use. Correct use can significantly extend the life of the unit and provide many important benefits. If you switch from a gasoline SUV to a diesel one without changing your habits, then your power unit will have a difficult time.

Engine use is a topic that can be discussed endlessly. Based on what features of the trip are violated by the owners of the equipment in comparison with the factory recommendations, it is very easy to find a number of important recommendations. This question concerns refueling of certain fuel and oil filling, service maintenance, as well as repairs. There are certain practical tips for reducing consumption and wear on a diesel engine. You can also remember the winter use of a diesel engine, which should be very careful. Considering all the categories presented, we can form some important tips for diesel powertrain owners. One has only to say that everything said below applies to modern turbocharged diesel engines that are installed on mass passenger cars.

Refueling and maintenance are the two most important points of use

First of all, when buying a diesel power unit, you need to choose a normal refueling place. We are talking not only about the high-quality brand of the filling station, but also about the quality of diesel fuel, which does not always coincide. Use the recommendations of experts and check the quality of diesel fuel using simple tests. The fuel must not freeze, cloudy and must be clean in all conditions. It is also worth following the recommendations for maintenance:

• for a diesel power unit, many manufacturers set a slightly shorter service interval than for gasoline engines, but this is not always the case;
• you need to comply one hundred percent with all the conditions of service that are set by the car manufacturer, use only original materials at the service;
• when buying an unknown oil, you can say goodbye to the engine after 10-20 thousand kilometers, filters are also worth buying original and very high quality;
• special attention should be paid to the equipment diagnostics during the service - this will help to avoid the most unpleasant problems associated with the injection pump and the block head;
• it is necessary to repair the diesel engine immediately after the car has shown a problem, this will help to maintain a certain quality and the desired properties of the installation.

If a gasoline engine is sometimes operated successfully and with malfunctions, then such an idea will not work in diesel power units. It is necessary to use the services of a professional service for servicing the Common Rail, turbine, injection pump and cylinder head. It is these parts that most often fail and cause certain troubles during operation. A breakdown can completely destroy the unit.

How to drive a modern turbine diesel engine?

Current heavy fuel powertrains do not differ too much from gasoline engines. The issue of ride quality can be very serious, as improper operation leads to a number of problems. You need to remember the basic recommendations, as well as read the features and individual tips in the operating instructions for your car. Basic recommendations for such engines are as follows:

• use high torque at low rpm - do not spin the diesel engine to high rpm of the power unit;
• take advantage of the comfortable early gear changes and the excellent traction characteristics of the diesel vehicle, this will help to gain comfort;
• do not overheat the unit, prolonged operation at high speeds or off-road operation in the middle mode will disable the injection pump and other important modules;
• you shouldn't drive a diesel car - you buy a car for comfort and low consumption, so use all the important advantages of transport with such features;
• in the city, it is quite possible to drive at a speed of 60-70 kilometers per hour using the last gear - this is one of the favorite modes of operation of a diesel unit.

You need to understand that diesel has a completely different structure than the gasoline engine we are used to. There are a number of advantages, but there are also disadvantages. Therefore, you should always study the manufacturer's recommendations for using the car, otherwise you can get into an unpleasant situation. Use the highest quality travel solutions and always strive to comply with factory recommendations. This will help keep your machine running.

What are the important advantages of a diesel engine?

The diesel-type power unit is known for eating less fuel than a gasoline counterpart with similar power characteristics. This is true, but the diesel-type power unit is one of the spendthrift budget on the service, it requires more money to complete all the tasks. Therefore, it is worth highlighting such clean and undeniable advantages of a heavy fuel power unit:

• the possibility of early gear shifting, very good torque, which picks up the gearbox in any mode and rides well even in an unsuccessfully selected position;
• very high traction indicators directly during acceleration, that is, at low revs, the highest indicator of the optimal useful power of the unit appears;
• reduced fuel consumption compared to gasoline evens out the cost of operating a power unit on heavy fuel, so it will not cost you much more;
• the service life of the diesel engine, subject to all important recommendations, will be quite high, there are no problems with the device, many drive up to 500,000 km;
• the environmental cleanliness of emissions is much better than that of gasoline options, the absence of carbon monoxide, but there are particulate particles, and they often exceed the norm for a car of this class.

Today's powertrain designs are becoming more sophisticated and demanding. Therefore, you should carefully follow each update and study the engine, information and reviews about it before buying. One and the same unit in different generations of cars from the manufacturer can have completely different operating options. And in this case, you can get really disappointment when buying.

How to Operate a Diesel Engine in Winter?

The winter operation of a power unit with diesel fuel is somewhat more complicated. If gasoline does not freeze at all, in principle, then the cloud point of diesel fuel is -25 degrees Celsius. The freezing temperature already at -35 degrees excludes the operation of a car in such conditions. However, today there is diesel fuel with additives, which is used without problems in any conditions. There are a number of cautious points:

• in winter, it would be nice to install a turbo timer in a diesel engine, which would continue to slowly reduce the engine temperature after a trip, when you have already left the car;
• you should also choose winter fuel at the gas station, choosing an initially normal gas station, where you will not fill the tank with low-quality liquid;
• you can also use a number of additives to reduce the crystallization temperature of the fuel when the fuel poured into the tank turns into a gelatinous mass;
• after the diesel fuel turns into gel, you will have to take the car to a service, and on a tow truck, in order to clean the fuel elements and hoses for further use.

For these reasons, diesel cars in northern conditions are not the best option. In central Russia, such cars are quite acceptable and can perform their functions perfectly. In the south, there are no problems with their operation at all. Nevertheless, you need to take into account a number of features for the use of fuel and the quality of service for your car. We offer you to watch a short video about the features of a diesel car:

Summing up

Does it make sense to buy a diesel car? In economic terms, this makes little sense. But in terms of travel, your conditions will really change dramatically. You will be introduced to a new technology that completely opens up a new perception of road transport. There are a number of positive and a number of negative factors in the use of such transport. But diesel lovers often argue that the pros far outweigh the cons. Of course, all this is very arbitrary. You can buy a diesel engine and be extremely unhappy with the situation during the first breakdown in winter. But remember that the quality of operation directly depends on you.

You should also remember about the gas station, which can be normal and terrible. If a gasoline unit from a poor refueling simply increases consumption, then diesel fuel can destroy a number of expensive elements in the car. Therefore, in Europe, for example, operating diesel units is not problematic. On the other hand, there are always a number of difficulties in owning a car with such a unit. So if you are afraid of these difficulties, it is better to choose a gasoline car. If you want to try something new, feel free to buy a turbodiesel. Which engine would you prefer for personal use?

4-stroke diesel internal combustion engine. This is a "twin brother" of another engine - gasoline. Structurally, the "diesel" is not much different from the gasoline counterpart, but the principle of operation of these engines is different, which is why internal combustion engines have followed 3 different development paths.

Diesel engines are the most demanded powertrains used in a wide variety of industries. They are used to equip cars and trucks, stationary power plants, special equipment, ships and diesel locomotives. These are kind of "workhorses" that can be entrusted with the hardest work. Since their appearance in 1897, diesel engines have practically not changed the principle of operation and the general structure of the structure, but every year they are being improved in order to reduce their weight and dimensions, reduce fuel consumption and increase their power. Basically, modernization consists in the development of electronic systems that control the operation of the main systems and mechanisms of the motor in order to determine the optimal mode of its operation.

The main distinguishing feature of a diesel engine from its main gasoline competitor is the method of ignition of fuel in the cylinders, which ignites on contact with compressed air during the working stroke, which eliminates detonation inside the cylinders and makes it possible to increase the compression ratio, as well as use various pressurization systems that increase power.

The efficiency of any engine, including a diesel engine, depends on the amount of energy generated during the combustion of fuel in the cylinders. In this respect, the diesel engine is much more efficient than its gasoline counterpart, which is achieved due to a higher compression ratio, reaching 20-24 units, and more rational fuel consumption, which directly depends on the load. If we compare a diesel and gasoline engine of the same volume, the former will consume 1.5 times less fuel. The efficiency of a diesel engine is about 40%, and with the use of an additional pressurization system - all 50%, which is 1.5-2 times higher than that of a gasoline engine. Diesel engines in their structure have stronger and more reliable elements designed to work in high pressure conditions, so they are more durable. But the disadvantage of such motors is their large mass, noise during operation, difficult start at sub-zero temperatures. During operation, it is necessary to carefully monitor the serviceability of the plunger pair, on which the quality of the engine operation directly depends. Due to the fact that diesel engines justify themselves economically and in terms of efficiency, and with an increase in size, their benefit only increases, they are used in ocean and sea fleets, on all types of civil surface ships.

Engine device

The diesel engine consists of the following main systems and mechanisms:
- crank mechanism;
- gas distribution mechanism;
- starting system;
- supply system;
- cooling system;
- lubrication system.

The principle of operation of such a motor is as follows: fuel burns in the cylinders, releasing energy, which sets in motion a piston connected by a connecting rod to the crankshaft. Under the pressure of the piston, the shaft rotates, transmitting the torque further along the transmission to the drive wheels. The engine systems are responsible for starting the engine, supplying fuel, cooling and lubricating the working surfaces.

Diesel engines can be 2-stroke and 4-stroke. Both the first and the second are successfully used in certain areas and have their pros and cons. The advantages of 4-stroke engines are:
- efficiency;
- reliability;
- uncomplicated maintenance;
- relatively low noise level during operation.

Disadvantages of 4-stroke engines:
- 3 out of 4 cycles of the cycle are performed by inertia, and only one of them is the worker;
- sharp increases in load during the working stroke require more reliable and durable elements: connecting rod, cylinder sleeve, piston, etc.;
- the need to adjust thermal gaps;
- starts longer than 2-stroke.

The process of operation of a diesel internal combustion engine

As the name suggests, the working cycle of a four-stroke ICE consists of 4 strokes: intake, compression, expansion and exhaust. Four strokes correspond to two crankshaft revolutions and four piston strokes. Piston stroke is its movement from top dead center (TDC) to bottom (BDC) or vice versa. This is one of the most important characteristics of the engine, which determines the compression ratio of the fuel mixture, and hence the engine power.

The first stroke - the intake stroke - in a diesel engine is the intake of air through an opening intake valve. The piston moves from TDC to BDC, creating a vacuum in the combustion chamber, which helps to draw air into the inside of the cylinder.

The compression stroke is the process of compressing air as the piston moves from BDC to TDC with the valves closed. At the same time, the volume in the combustion chamber decreases, the pressure increases and the temperature rises. A little earlier than the piston reaches its upper position, diesel fuel is injected through the injector. It ignites on contact with hot air.

The expansion stroke (stroke) is characterized by a sharp increase in temperature and pressure due to fuel combustion. The gases press on the piston, moving it from TDC to BDC, which is the main driving force of the motor.

The exhaust stroke is the removal of exhaust gases from the combustion chamber through the exhaust valve. The piston rises to TDC, pushing the combustion products outward.

After the exhaust stroke, the intake stroke starts again, and so on in a circle.

The performance of all 4 stroke engines is the same, be it a diesel engine or a gasoline engine.

Fuel mixture combustion chamber

Different models of diesel engines differ in structure. One of the important features is the design of the combustion chamber. Combustion chamber - the space where the fuel is directly burned.

The unseparated chamber is located in the piston structure itself or above it, the fuel enters it at the intake stroke, where it ignites on contact with hot air. This is the simplest option, which also reduces fuel consumption, but the engine itself runs very loudly.

Another option is a divided chamber, that is, a chamber that is not located in the cylinder, but at the entrance to it and is connected to them by a channel. The fuel is fed into the chamber, where it mixes with the vortex air flow, which better distributes its droplets over the volume of the combustion chamber and promotes its complete combustion. This option is suitable for small installations and cars, but it significantly increases fuel consumption.

Based on the design of the piston and combustion chamber, there are different methods of mixture formation in diesel internal combustion engines:

- volumetric mixing is the simplest option. The combustion chamber is the space between the piston, the walls and the cylinder head. Fuel is injected under pressure through the injector nozzles. It is important here that the fuel droplets are evenly distributed throughout the entire volume and thoroughly mixed with hot air, therefore, a vortex-like flow of a fuel charge must be organized in the combustion chamber, and the fuel itself must be supplied under high pressure;

- volumetric-film mixing is used in high-speed engines with small cylinder bore. This is exactly the case when the combustion chamber is partially housed in the piston structure. In engines of domestic production, such chambers have the shape of a truncated cone. When the charge is injected, the fuel hits the surface of the combustion chamber, forming a "film", after which it evaporates almost immediately. Vortex flows generated under the influence of piston movement make it possible to evenly distribute fuel droplets throughout the volume;

- prechamber mixing provides for the presence of a prechamber located in the cylinder cover. It is connected to the main combustion chamber by small channels with diameters not exceeding 1% of the piston diameter. The volume of the pre-chamber is up to 30% of the total volume of the chambers. In shape, it can be oval, cylindrical or spherical;

- vortex chamber mixing occurs due to vortex air flows, which makes it possible to mix the fuel charge with air as much as possible even at a low pressure of its supply to the combustion chamber. For such a mixture formation, a separate chamber is required, consisting of two parts: a vortex and a main one. During the compression stroke, air from the main chamber is displaced into a vortex chamber, which has a spherical or cylindrical shape. The air flow creates vortex movements, moving in a circle, and at this time a fuel charge is supplied from the nozzle under a pressure of up to 12 MPa. Since the air wave is in motion, the droplets are evenly distributed throughout its volume.

Engine layout

4-stroke diesel engines differ not only in the structure of the combustion chamber, but also in the number of cylinders and their mutual arrangement. It is clear that the more cylinders, the more powerful the engine and the larger it is. Different layout options make it possible to reduce its dimensions. Depending on the arrangement of the cylinders, the engines can be:

1. Inline.

All cylinders are arranged in a row. This design of engines is the simplest, the parts for them have a simple production technology.

2. V-shaped engine.
The cylinders in such an engine are arranged in the shape of the letter V, in two planes, in two rows at an angle of 60 0 or 90 0. The angle formed between them is the camber angle. The advantage of this engine is power. Its dimensions can be reduced by displacing other important components into the camber. Its length is shorter and its width is greater. But due to the complexity of such structures, it can be difficult to determine their center of gravity.

3. Boxer engines (marking B) .
They are relatively balanced; to reduce vibration, all elements are placed symmetrically. Their design feature is the central shaft mounting on a rigid block. This also affects the degree of vibration. The camber angle is 180 0.

4. Row-offset aggregates (VR markings).
This arrangement is distinguished by a small camber angle (15 0) of a V-shaped engine in collaboration with an in-line analogue. This makes it possible to reduce the dimensions of the longitudinal and transverse units. VR marking stands for V - shaped, R - in-line.

5. W (or take V) - shaped .
Most complex engine. Known for two types of layout.
1) Three rows, large camber.
2) Two VR layouts. They are compact despite the large number of cylinders.

6. Radial (radial) piston engine.
It has a small length with a dense placement of several pieces of cylinders. They are located around the crankshaft with radial beams with equal angles. It is distinguished from others by the presence of a crank mechanism. In this design, one cylinder is the main one, the rest - trailed - are attached to the first along the periphery. Disadvantage: At rest, the lower cylinders can suffer from oil leakage. It is recommended to check that there is no oil in the lower cylinders before starting the engine. Otherwise, water hammer and breakage are possible. To increase the size and power of the engine, it is enough to lengthen the crankshaft by forming several rows - stars.

Electronic engine tuning

Modern diesel engines are increasingly equipped with electronics. Sensors that monitor the load, control the amount of supplied fuel and the composition of the fuel charge, send signals to the central control unit, which selects the most efficient and economical operating mode. With a careful influence on this system with the help of additional equipment, you can increase the engine power within certain limits - this is called chip tuning. It should be noted right away that chip tuning is not omnipotent, it can improve engine performance within the prescribed safety margin and often leads to premature wear of systems.

To increase the power of a diesel engine, special modules or blocks can be used:
- a block that changes the injector control impulses;
- block for substitution of high pressure fuel pump modes (high pressure fuel pump);
- a unit that changes the readings of the fuel accumulator pressure sensor;
- mode optimization module.

The first option is the most famous among auto-tuning enthusiasts. The principle of operation of such a unit is that it blocks short-term impulses of preliminary and subsequent opening of the nozzle needle, which reduces fuel consumption. The unit can be installed on almost any model, but its operation reduces the resource of the engine and affects the quality of combustion of the fuel charge.

The second option can only be used on certain engine models. The principle of operation of this unit is that it gives a signal with underestimated values ​​of the pressure in the system, which leads to its increase. In this case, the injection pump and injectors "suffer", but the engine power actually increases, and the fuel consumption decreases.

The third option involves connecting a unit that sends a signal to the ECU about the permissible low pressure value in the fuel accumulator. As a result, the pressure is automatically increased and the time and the rate of fuel injection are determined in a new way. This increases power and saves fuel, but the service life of the injection pump and particulate filter decreases, carbon deposits form on the cylinder walls, and the engine begins to "smoke".

The safest and most effective is the fourth option. The module connected to the power supply system does not substitute the necessary numbers for the true values ​​of the operating parameters, but sends a signal to the ECU about the need to change the duration of fuel injection. Unlike the previous units, this module does not cause any harm to either the engine or the high-pressure fuel pump, so the resource of systems and mechanisms will not decrease. The disadvantage of this method of increasing power is its high cost, limited application and design complexity. It does not give an instant effect - its effect can be felt only after a while.

There are other ways, including using equipment that changes the true stoichiometric values, but using them can lead to serious engine problems.

One of the major problems with diesel engines is the so-called "engine run". This is an abnormal operation of a diesel engine, in which an uncontrolled increase in the engine speed occurs. This behavior is usually observed after startup or during sudden load shedding. There are two main reasons for the runaway: a malfunction of the high pressure fuel pump and the ingress of a large amount of engine oil into the combustion chamber.

Description of the structure

A diesel engine is a reciprocating piston engine with the same basic design and duty cycle as a gasoline engine. The main difference between a diesel engine and a gasoline engine is the fuel used and the way the fuel is ignited to ensure combustion.

Work

Diesel engines use the heat of compression to ignite the air / fuel mixture in the combustion chamber. This ignition is performed using high compression pressure and diesel fuel injected into the combustion chamber at very high pressure. The combination of diesel fuel and high compression pressure allows autoignition to start the combustion cycle.

Cylinder block

The cylinder blocks of a diesel engine and a gasoline engine are similar to each other, but there are some differences in their design. Most diesel engines use cylinder liners rather than cylinders made as part of a block. When cylinder liners are used, repairs can be carried out allowing the engine to operate for a long time. On diesel engines that do not use cylinder liners, the cylinder walls are thicker than those on a gasoline engine with the same displacement. To increase the bearing surface of the crankshaft, diesel engines have heavier and thicker main webs.

Wet cylinder liners

Wet cylinder liners used in diesel engines are similar to those used in gasoline engines. The physical dimensions of the liners may vary to suit the operating conditions of the diesel engine.

Crankshaft

The crankshaft used in diesel engines is similar in design to the crankshaft used in gasoline engines, but with two differences:

Diesel engine crankshafts are usually forged rather than cast. Forging makes the crankshaft more durable.
... Diesel engine crankshaft journals are generally larger than gasoline engine crankshaft journals.
The enlargement of the journals allows the crankshaft to withstand heavy loads.

Connecting rods

The connecting rods used in diesel engines are usually made from forged steel. Connecting rods for diesel engines differ from those for gasoline engines in that the covers are offset and have fine teeth on the connecting rod interface. Offset, fine-toothed design helps hold the bonnet in place and relieves stress on the connecting rod bolts.

Pistons and piston rings

The pistons used in light duty diesel engines look similar to those used in gasoline engines. Diesel pistons are heavier than gasoline engine pistons because diesel pistons are usually forged steel rather than aluminum, and there is a larger internal material thickness.

Compression rings used in diesel engines are usually made of cast iron and are often plated with chrome and molybdenum to reduce friction.

Cylinder head

Externally, the cylinder head of a diesel engine looks a lot like the cylinder head of a gasoline engine. But there are many internal design differences that make diesel engines different and original.

On a diesel engine, the cylinder head itself must be much stronger and heavier in order to withstand high heat and pressure loads. Combustion chamber design and air ducts on diesel engines can be more complex than on gasoline engines.

Several designs of combustion chambers are used in diesel engines, but two designs are most common: an undivided combustion chamber and a vortex chamber.

Non-split combustion chamber design

The most common type of combustion chamber for a diesel engine is a split chamber, also known as a direct injection combustion chamber. In an undivided design, turbulence (swirl) of the intake air is ensured by the shape of the air intake duct. Fuel is injected directly into the combustion chamber.

Vortex chamber design

The vortex chamber design uses two combustion chambers for each cylinder. The main chamber is connected by a narrow channel with a smaller vortex chamber. The vortex chamber contains a fuel injector. The vortex chamber is designed to ensure the start of the combustion process. Intake air is introduced into the vortex chamber through a narrow channel. Then fuel is injected into the vortex chamber, and the resulting mixture ignites. After that, the burning mixture enters the main combustion chamber, where it ends its combustion, forcing the piston to move downward.

Valves and valve seats

Diesel engine valves are made from special alloys that are able to work well under the high heat generation and pressure typical of a diesel engine. Some valves are partially filled with sodium, which helps dissipate heat. A large percentage of the heat is transferred from the valve head to the valve seat. To ensure adequate heat transfer, particular attention must be paid to the valve seat width.

A wide valve seat has the advantage of being able to transfer more heat. However, a wide valve seat also has a high potential for carbon build-up that can cause valve leaks. A narrow valve seat provides a better seal than a wide valve seat, but does not transfer the same amount of heat. In a diesel engine, a compromise is required between wide and narrow valve seats.

Plug-in valve seats are often used in diesel engines. The inserts have the advantage of being replaceable. Plug-in valve seats are made from special metal alloys that withstand the heat and pressure of a diesel engine.

Fuel supply system

Conventional design

In a conventional diesel fuel delivery system, fuel is drawn from the fuel tank, filtered and supplied to a high pressure pump. The high pressure fuel is brought to the required pressure and supplied to the fuel manifold, which feeds the fuel injectors. The injection control system at appropriate times activates the injectors, which, during the compression stroke of the piston, inject fuel for its subsequent combustion.

Common rail design

Common rail diesel engines use independent fuel pressure and fuel injection systems. The high pressure fuel pump draws fuel from the tank and supplies it through the pressure regulator to the common rail. The high pressure pump consists of a low pressure transfer pump and a high pressure chamber. Fuel injection is controlled by the Powertrain Control Module (PCM) and Injector Control Module (IDM), which adjusts the injector open time based on engine operating conditions.

The common rail design significantly reduces exhaust emissions and minimizes operating noise. This is all a consequence of greater control over the combustion process. Fuel pressure adjustment and injector operation phases are controlled by UM and PCM. The injector design has also been redesigned, which now allows for preliminary (pre-injection) and post-injection (post-injection) fuel injection at various stages of the compression stroke and power stroke.

Improved fuel control results in cleaner, more consistent combustion and proper cylinder pressure. This has an effect on reducing emissions and noise during operation.

Lubrication system

The lubrication system used in diesel engines is similar in principle to that of gasoline engines. Most diesel engines have some type of oil cooler to help remove heat from the oil. Oil flows under pressure through the engine passages and returns to the crankcase.

The lubricating oil used in diesel engines is different from the oil used in gasoline engines. A special oil is necessary because more oil contamination occurs when a diesel engine is running than in a gasoline engine. The high carbon content of diesel fuel causes the oil used in diesel engines to change color shortly after being used. Only engine oil that is specially formulated for diesel engines should be used.

Cooling system

The diesel engine cooling system usually has a larger filling volume than the gasoline engine cooling system. The temperature inside a diesel engine must be carefully controlled because heat is used to self-ignite the fuel.

If the engine temperature is too low, the following problems occur:

Increased wear
... Poor fuel economy
... Accumulation of water and sediment in the engine crankcase
... Loss of power

If the engine temperature is too high, the following problems occur:

Increased wear
... Bully
... Detonation
... Burnout of pistons and valves
... Lubrication problems
... Jammed moving parts
... Loss of power

Fuel injection system

The diesel engine works on the principle of self-ignition. The intake air and fuel are compressed in the combustion chamber so much that the molecules heat up and ignite without the aid of an external ignition spark. The compression ratio of a diesel engine is much higher than that of a gasoline engine. The compression ratio for diesel engines with direct air intake is approximately 22: 1. The turbo diesel engines have a compression ratio of 16.5-18.5: 1. Compression pressure builds up and the air temperature rises from approximately 500 ° C to 800 ° C (932 ° F to 1,472 ° F).

Diesel engines can only be operated with a fuel injection system. Mixing occurs only in the injection and combustion phases.

At the end of the compression stroke, fuel is injected into the combustion chamber, where it mixes with hot air and ignites. The quality of this combustion process depends on the quality of the mixture formation. Because the fuel is injected so late it doesn't have much time to mix with the air. In a diesel engine, the air-fuel ratio is constantly maintained at more than 17: 1, thus ensuring that all the fuel is burned. Refer to the publication "Engine and Systems Operation" for more information.

Diesel engines for cars are different, and it's not just the volume and number of cylinders, so let's try to briefly review the modern market and find out which of the engines are the most reliable.

To whom did the ratings give the leadership?

Russian people always associate the word “diesel” with the same: the smell of diesel fuel from a passenger bus, black fumes from a passing truck, vintage jeans and a watch of the brand of the same name. Nevertheless, for the majority of Europeans, the word derived from the surname of the German inventor is synonymous with a reliable, inexpensive and powerful "heart" of the car. In our country, its popularity is not so high, apparently due to weather conditions and knowledge that diesel fuel thickens in the cold.

Reliability ratings, and especially for cars, is a thankless task. How many opinions, so many lists, in which the compiler simply expresses his view of a particular subject. That is why we would like to draw your attention to the fact that the rating given below does not pretend to become an indisputable truth, but just an attempt to systematize the data, knowledge and (partially) the personal point of view of the compiler.

In search of an answer to the question of which diesel engine takes the leading place in the complete set of passenger cars, one can notice that some ratings call the best products of the Mercedes and BMW concerns. However, the situation in the world of the automotive industry today is somewhat different, let's try to figure it out.

As the ratings of the world's major car dealerships show, the days when diesel engines of passenger cars were small copies of units installed on heavy trucks are gone. The well-known Volkswagen concern was especially successful in the production of such engines, which developed the 1.9 TDI engine. Today it ranks first and is considered the most balanced in terms of dynamics and power.

Thanks to the latest engineering solutions, in particular, an updated turbine and an increase in pressure in the combustion chambers, it was possible not only to achieve unique environmental characteristics, but also to reduce it. Moreover, the power remained at the same level (90–120 hp). The newest cars in the Passat series are now equipped with the highest performance engine (BlueMotion equipment). Fuel consumption is 3.3 liters per 100 km.

Diesel winners of the car market

The second place is occupied by a modification of the engine with three turbines, owned by the German company BMW. For the first time, this unit was presented a little ago. It has 6 cylinders and, having a volume of 3.0 liters, is capable of developing a capacity of 381 liters. With. These engines are equipped with the latest cars of the 5th and 7th series, as well as heavyweight crossovers with the X5 and X6 indices. Convertibles with serial number 6 are equipped with a modification. True, it has two turbines, due to which the power is reduced to 313 liters. With.

Not so long ago, potential buyers were presented with cars, whose engines have four turbines, and with a torque of 800 Nm, the power will be in the range of 390-406 hp. With.

Car with a four-turbine engine

The third place in our rating was taken by the American company of industrial diesel engines Cummins, which produced a super-powered engine commissioned by the famous Dodge company. In fairness, it should be noted that overseas manufacturers did not pay too much attention to diesel engines, preferring to develop gasoline ones. However, the recent increasing demand for cars with units that consume diesel fuel forced them to pay attention to the production of diesel engines.

The model proved to be quite powerful (240-275 hp), but in an attempt to occupy a "diesel" niche in the market, the Americans cheated and passed off the Italian concern Fiat for their development. The model of such an engine was equipped with a Maserati Ghibli, but due to the crisis, production was given to state industrialists.

This engine was recognized not only as the most environmentally friendly, but also the most innovative: in its production, metals used in the space industry and filters for plasma cleaning of fuel were used. The fact that the engine took only the third place is a "merit" of a narrow focus. It is installed only on sports cars and Dodge Ram pickups. In terms of efficiency, it can give odds to its competitors: the consumption is only 8.5 liters per 100 kilometers.

Who is not far behind the top three?

The Koreans who burst into the world automobile market 20 years ago not only managed to take a worthy place on it, but also "move" in the ranking of Japanese giants. Having come a long way "from electric kettles to mining trucks", they also do not want to miss out on their benefits, which promises an increased demand for cars equipped with diesel engines.

As always, Asian manufacturers acted very cunningly: not wanting to overhaul production and compete with Europeans and Americans in the power of the units, they managed to create a 1.7-liter engine that can produce 110-136 liters. With. Do not rush to wrinkle your nose contemptuously! With such rather modest (in comparison with products of other manufacturers) data, the Hyundai diesel engine has such incredible torque that it is not inferior in dynamics to gasoline units with a capacity of 150-170 hp. With.

It must be said that the Hyundai i40 supplied to the European market is equipped with such a unit. In Korea, diesel engines have not found widespread use either (or the wave of "fashion" has not yet reached there), and therefore they are still installed only on export vehicles. Recently, the same unit appeared on the crossover with the ix35 index, and now it is equipped with such popular cars as the Grandeur and Sonata. Fuel consumption, however, is higher than that of competitors, but Koreans do not seek to surprise anyone. Their task is to supply reliable "workhorses" capable of average fuel consumption, in this case 5.5 liters per 100 km.

Having “squeezed out” a sufficient amount of power from cars and having won its cell in the market, the Japanese concern Toyota now has no sense in proving something to someone. The concept, to which the manufacturers have thrown all their efforts, is ecology and economy while maintaining sufficient power. And they succeeded. When creating the engine for their compact car called Urban Cruiser, they thought that the inhabitants of metropolitan areas would not only be comfortable to move around the city, but also would not have a "calculator" that calculates fuel costs in their heads.

One of the smallest diesel units today is a 1.4 liter engine with a capacity of only 90 liters. With. This is the fifth place in our ranking. Such parameters, however, do not interfere with the creation of torque, which makes it easy to "pull" the four-wheel drive vehicle. The consumption of diesel fuel, depending on the mode of travel, ranges from 4 to 6 liters per 100 km.

So which one is the most reliable?

This question is a bit naive, since this parameter depends on many factors, including driving style. But if you choose the best of the above list, then the reliability priority will be given to the Americans Cummins with a Dodge engine.

And it's not about power or fuel consumption per 100 km. Most likely, the materials used in production play a role. The cylinder block is made of high-carbon cast iron, capable of withstanding not only high pressure, but also significant temperature conditions. And its pistons are made of a special aluminum alloy, which is used in parts of spacecraft. This means that they are able to withstand both long-term operation under extreme conditions, and a sharp increase in load when changing the speed mode.

Also, the engine is equipped with a Common Rail fuel injection system, which, despite a rather capricious attitude towards the quality of diesel fuel, not only significantly saves its consumption, but also plays a decisive role in reducing engine noise. It is these engines that are equipped with both sports cars and off-road vehicles. That is, it is precisely those specimens of the automotive industry, the operation of which takes place in extreme conditions, requiring from the engine not only unsurpassed power, but also impeccable reliability.

If we talk about the rating of cars that are suitable for Russian roads, it is best to pay attention to samples of Japanese production. It will not necessarily be Toyota (to the engine of which, by the way, no Russian car enthusiast has any complaints).

For our vast expanses, Mazda, Honda, Nissan or the newly revived Datsun will do just fine. Subaru has shown itself quite well in operation.

The fact is that European cars equipped with a diesel engine are very sensitive to our diesel fuel, the cleaning quality of which leaves much to be desired. As shown by numerous reviews of car owners, Japanese cars are less prone to malfunctions when using diesel fuel, thanks to numerous cleaning devices, electronic devices and built-in pre-heaters that prevent diesel fuel from freezing at low temperatures.

As you know, diesel engines are more expensive to maintain and even more expensive to repair, due to the fact that their units and parts (high pressure fuel pump or high pressure fuel pump, pump nozzle, turbocharger, nozzle) are made with the highest possible precision. Moreover, they are, as a rule, more economical than gasoline ones and have a higher efficiency (efficiency) - by 10-14 percent. In addition, modern diesel engines have great power and excellent throttle response. And for an even greater increase in power and traction characteristics, diesel engines are equipped with a turbocharger and an intercooler.

The principle of operation of a diesel engine and its difference from a gasoline counterpart.

The principles of operation of diesel and gasoline engines, as noted above, are completely different.

In gasoline internal combustion engines (carburetor, injection), the preparation of the mixture, as a rule, takes place in the intake tract: a ready-made mixture is fed into the cylinder, which ignites there with the help of a spark plug at the moment of compression.

In diesel engines, this is not the case, and mixture formation occurs directly in the cylinder. In this case, the igniter is air, which, when compressed, heats up and ignites the diesel fuel. This fuel itself is fed into the combustion chamber by a nozzle and a high-pressure fuel pump (pump-injector) under high pressure.

Now let's get acquainted with this process in more detail, by clock. By the way, the number of the latter in diesel and gasoline engines is equal to (four). Let's consider each of the measures.

The first stroke of a diesel engine is the intake stroke.

During the period of the first stroke, the piston moves from top dead center (TDC) to bottom (BDC). At this stage, the intake valve is open, while the exhaust valve is naturally closed. When the piston moves to nmth, a vacuum is created and the engine cylinder is filled with air, which, before entering the cylinder, is cleaned of mechanical impurities in the air filter.

The second measure will be the compression cycle.

At this point in time, the valves (intake and intake) are closed and the piston moves from nmt to vmt. And since the valves are closed, the air has nowhere to go, so it compresses, creating high pressure, and heats up - up to 800 degrees Celsius.

The third cycle is the expansion cycle (working stroke).

During the movement of the piston to TDC, diesel fuel is fed into the cylinder under high pressure (from 150 to 300 Bar) by means of a nozzle and is sprayed there. In the process of spraying fuel, it mixes with hot air and, consequently, its subsequent ignition. When the mixture is burning, the temperature in the cylinder rises rapidly - up to 1750 -1800 degrees Celsius. At the same time, the pressure rises, which reaches 10-12 MPa. Gases are formed that push the piston from top to bottom. Moving downward, the piston performs its prescribed work. In nmt, the pressure decreases with the temperature.

The fourth measure is the final one, it is also the beat of the release.

The piston moves up. The exhaust valve opens and gases tend to leave the combustion chamber through channels in the cylinder head (cylinder head) into the exhaust manifold. Further, the gases enter the muffler, where they are cleaned (diesel particulate filters are installed in modern diesel engines) and into the environment. At this time, the temperature in the cylinder decreases, to 450-540 degrees, and the pressure drops - to 10-20 Bar.

Video.