Diesel engine injection pump: device, principle of operation, diagnostics and adjustment
Every driver knows that diesel and gasoline engines have a different fuel injection system. So, the most important component of the first is considered a diesel engine injection pump.
Fuel pump: what is it?
In the people of the high pressure fuel pump is called the diesel engine injection pump. Such a unit is a very complex and indispensable element of the design, since the main task of the pump is to deliver diesel fuel under fairly high pressure. A diesel engine injection pump, the price of which is indicated in the article, is capable of ensuring correct and very accurate fuel supply to the cylinders of a diesel engine under the necessary pressure. Fuel is supplied in very precisely measured portions at the most suitable point in time.Each of them ideally corresponds to the motor load.
Diesel engine injection pump may vary in injection methods. There are products with a battery injection type, as well as models of direct action.
The first devices are characterized by the fact that the working drive of the plunger is directly affected by compressed gases in the cylinder of the internal combustion engine. Or the impact may occur due to the operation of the springs. Please note that there are models of pumps with a hydraulic accumulator, which are quite often found in very powerful diesel internal combustion engines.
The second type of device can be described as a product having a mechanical plunger drive. This suggests that the phenomena of injection and injection take place simultaneously. The diesel engine injection pump is capable of delivering the correct dose of fuel to each cylinder individually.
The main causes of faults
Please note that diesel engine injection pump, the malfunctions of which are described below, is very expensive equipment, which is particularly demanding on the quality of the fuel itself, as well as any materials for lubrication.Do not forget that the use of low-quality low-cost fuel very quickly leads to a malfunction of the nozzle, responsible for the flow of important processes such as injection and spraying.
There are several signs that indicate that it is necessary to repair the pump. These include:
- a significant increase in fuel consumption;
- from the exhaust pipe you will notice an increased opacity of uncharacteristic color and odor;
- during operation of the engine will be published noises and sounds;
- recoil and power of the internal combustion engine drops significantly and noticeably;
- more and more often it will be noticeable that the car does not start so easily and not so quickly.
Modern diagnostic indicators
Diagnostics of diesel engine injection pump are important measures taken to prevent problems with the engine. The most modern motor devices are equipped with a special convenient fuel injection system. Such an electronic control unit is capable of metered fuel supply to cylinders, while accurately distributing this process over time.This system is also able to determine how much diesel fuel is needed.
So, if the car owner starts to notice even the slightest interruptions in the system, then you need to urgently send your "iron friend" to the diagnosis. Timely contact with a car service will be able to influence the process of repair or replacement of equipment.
During the diagnostics, car service specialists will be able to determine the following health indicators:
- the frequency with which the shaft rotates;
- how evenly fuel is supplied;
- pressure indicators and determination of its stability.
Everyone knows the global problems associated with the ecology of our planet. Therefore, strict standards for the manufacture of engines led to the fact that the massive mechanical injection pump of a diesel engine, reviews of which you can read in this article, began to be replaced by modern systems that have electronic adjustment. In addition, the pump, working on the mechanics, can not provide the correct, fast and accurate flow of diesel fuel. Also, he is not able to react with lightning speed to very rapidly changing modes of operation of the motor.
Popular manufacturers such as Nippon Denso, Bosch and many others are already using electronic diesel fuel supply control systems. In addition, the VE fuel pump was involved in such developments. The use of modern systems has led to the possibility of obtaining the fastest possible supply of fuel separately to each working cylinder.
Such systems appealed to many drivers, since the instability of the combustion process of combustible-air masses decreased between cycles. Also, importantly, the unevenness in the operation of the engine at idle speed has significantly decreased. Some models were equipped with a special quick-action valve, dividing the fuel injection timing into two phases. This process helped reduce the stiffness of the combustion itself.
Due to the accuracy obtained, the developers were able to provide the minimum amount of harmful toxic emissions into the atmosphere. This is facilitated by the almost complete combustion of the fuel itself. But the effectiveness of such a unit significantly increased the efficiency of the motor and led to the final power.Electronic systems work thanks to the diesel engine injection pump (the principle of operation is described in this article). It is important to know that a high pressure fuel pump can be controlled using a special device. It allows you to adjust the position of the dispensers.
How the system works
The electronic control unit receives important signals from different sensors in a timely manner. This should take into account such characteristics as the position of the gas pedal, the fuel temperature, the frequency with which the motor shaft rotates, as well as the temperature of the liquid for cooling. The computer is designed in such a way that it has the ability to obtain data such as the speed of movement of the car, the raising of the nozzle needle, as well as the temperature and air pressure at the inlet. The electronic control system is able to process all the information received from the sensors and transmit the signal to the high-pressure fuel pump. And this, in turn, ensures the correct and timely supply of fuel to the injectors.
Also, the computer additionally takes into account the angle of injection, depending on the operating conditions of the vehicle.Even the smallest load will be noticed by the electronic control system, and the pump will receive a signal that it is necessary to increase the amount of fuel entering the system. Also, the computer is able to control the activity of the glow plugs. He pays attention to such parameters as the time spent on the glowing itself, as well as the time period after that. Do not forget that these processes are directly dependent on temperature.
Device for diesel engine injection pump
Consider the device of the high pressure fuel pump on the example of the distribution unit. The first thing to consider is that pumps are single-service and double-service. At the same time, even one section of the device can feed a mixture of fuel into several injectors at once.
So, the pump referred to in this article consists of a reduction valve, a mode regulator, a drainage nozzle, and also a pump section housing. The device also has fuel supply elements, a housing, a hatch responsible for the injection advance, as well as an electromagnetic valve and a special plunger drive device. Of course, a high-pressure fuel pump has an effective but very complicated device, so it will not be so easy to diagnose.But repair is generally a very difficult task, even for a well-equipped service center.
Repair of fuel pump
A variety of causes can cause damage to a high-pressure fuel pump. Most breakdowns repair their own hands is simply impossible. Even in a special car service, it is considered quite a difficult task to perform. But if the equipment needs to be replaced with any parts, then this can be done in the garage. However, experts strongly do not recommend doing it yourself, especially without prior diagnosis. In any case, the adjustment of the injection pump of a diesel engine should be carried out using a specialized stand.
The most common cause of damage is the wear of the diesel engine itself. This can be determined even by ear. A broken engine is too loud and makes strange noises. Also, each time the engine starts to get harder, and there are large power losses. Do not use fuel of poor quality. At the work of the motor it will affect very quickly.Note that a very important role for the health of the car electronics plays.
In order to make repairs, most often you just need to replace worn parts. But even for this you need to disassemble the device. Of course, you can do this in your garage. But if you do not have special skills, it is better not to risk and go to the car wash.
Please note that the adjustment of the high-pressure fuel pump should be carried out only on special stands by highly skilled workers. During this process, specially selected nozzles are commonly used. Before starting to adjust the pump, all the nozzles must be properly adjusted on a special stand, taking into account all the technical parameters of this model. After the pump is adjusted, each nozzle is mounted on a cylinder of a suitable section of the device, which was adjusted together with this nozzle.
How is cyclic feed regulated
A very important part of adjusting a high-pressure fuel pump is the process of controlling the fuel supply itself at a nominal rate.To do this, you need to install the pump rail in the position of the nominal flow with a special nut. During the nominal rotational speed, the cyclic delivery of each section is usually measured while monitoring the fuel level.
Rules of operation: the choice of oil
The service life of a diesel engine injection pump is directly dependent on proper operation, as well as on the fuel and other materials you use.
For proper and long operation of the device, it is very important to fill in the engine oil in time. It should be ideally suited to your engine and have all the necessary characteristics for it. Experts do not recommend changing the brand of oil very often, as this can lead to the formation of deposits that are not so easy to dissolve. Replace oil and filters once every 7,500 kilometers.
Pledge of long service
In order for the engine to work properly for many years, you need to follow certain rules, namely:
- Perform timely replacement of the timing belt. This should be done every 50-60 thousand kilometers.
- Change the fuel filter every 10 thousand kilometers.
- Warm up the engine well and try not to drive at high revs.
- Conduct timely equipment diagnostics.
Few final words
The cost of the device itself is about three hundred dollars (types of diesel injection pump described in this article). In no case do not ignore the diagnosis, because even the smallest trouble can make you a victim or perpetrator of road accidents. Carry out all repair work only in specialized services. Trust your car exclusively to highly qualified professionals. When replacing worn parts, buy only original products from the manufacturer.
Timely diagnosis and use of high quality materials will be the key to a long life of a diesel engine. Treat your “iron friend” with respect and diagnose all failures in time. Only in this case, he will serve you for a very long time.