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How to manage diesel, diesel engine fuel system maintenance knowledge

manage diesel

With rising fuel prices, fuel consumption for construction machinery users increasingly pay attention to it. Daily use in construction machinery, the operator not only to master the appropriate method of operation, but also often on the electronic control system, hydraulic system and diesel engine fuel system and intake system maintenance, to ensure the engine work in the best condition.
Maintenance of the machine is important, but you know that before performing these maintenance, the fuel must also know how to correctly manage and use.

Engine failure for many reasons, such as oil, water, gas and other mismanagement.
Since the work load, environmental issues, the vast majority of construction machinery will be in a more harsh working conditions of use. For a piece of equipment is concerned, it’s the quality of life and the maintenance of direct closely. repair-guidebook.com from a world-renowned brand sales data obtained at the statistics was informed that the brands of construction machinery products engine failure, nearly 7 in Chengdu because of oil, water and gas caused by poor management. This time, give you a brief introduction, on the “fuel management” of relevant knowledge.

One, causing oil pollution What are the factors?
Often, we are talking about fuel contamination generally refers to the following situations:
(1) high water content
(2) sand, dust
(3) high content of heavy oil
(4) a high content of paraffin
(5) sulfur content
Here, we have the above-mentioned five kinds of contamination of the fuel to analyze the situation.
1, the water hazard
Our common-rail diesel engine with an example:
In simple terms, the high water content in the fuel, will accelerate the fuel pump plunger, plunger sleeve, nozzle needle wear, resulting in injection pressure drop, poor atomization, black smoke, the engine power loss and other failures.

Injector needle assembly, in the middle of the needle valve cone is very easy to wear, which affects the injector fuel injection quantity

Injector needle assembly, in the middle of the needle valve cone is very easy to wear, which affects the injector fuel injection quantity

Normal quality diesel water content should be less than 0.03%, the water content is too high will have significant impact on fuel quality, including:
(1) Fuel moisture content increased viscosity decreased, reducing fuel injectors, fuel pumps and other fittings for lubrication performance while also reducing needle valve sealing face and other parts of the lubrication protection, accelerate the wear parts.
(2) from the outside of the water itself is not clean diesel fuel, it may contain large amounts of impurities, and a variety of inorganic salts, may exacerbate the injector surfaces and the sealing surface with wear and corrosion.
(3) the water content increases, will lead to bacteria multiply within the mailbox. Many countries on the world market the sulfur content of diesel is higher, thus more acidic substances, destruction of acid-base balance of fuel, increasing the degree of corrosion of parts.
(4) high water content of the fuel, its low viscosity, fine filter of the filter surface can not form a good film to assist filters filter out impurities, make more large foreign particles through the filter, and the filter in the water and would have been under the influence of impurities greater damage, making the filtering capacity deteriorated.
In short, the high water content of the injector fuel impact is very serious, while the other pumps and other fuel system components have damage, but is more prone to failure injector, and a more direct impact on engine performance.

2, sand and dust hazard
Fuel, if mixed with too much sand and dust, will accelerate the fuel pump plunger, plunger sleeve, delivery valve, fuel pump needle, transfer pump check valve wear, can cause severe injection pressure drop, fog of poor, black smoke, the engine power down and so on.

The oil valve because of the use of poor quality fuels caused serious wear and tear

The oil valve because of the use of poor quality fuels caused serious wear and tear


(1) in the fuel sand and dusty, will produce oil nozzle wear, affecting the quality of atomization.
(2) in the fuel sand and dust, vanadium, sodium and other alkali metal element, the internal temperature in the engine is formed on the heating surface tube fouling high viscosity.
(3) high temperature fouling, there is more of vanadium pentoxide and by the formation of sodium sulfate-containing complex salt, they can damage the metal surface oxide protective film, and thus be a valve, fuel pump plunger, column plugs and other parts of sets of high temperature corrosion.
3, the dangers of heavy oil
Heavy oil, also known as fuel oil, dark black liquid, mainly crude oil processing at atmospheric pressure, vacuum residue, residue cracking, catalytic cracking diesel and diesel oil and other raw materials blending.

Extraction of heavy crude oil gasoline diesel heavy residual oil, which is characterized by high molecular weight, high viscosity. The proportion of heavy oil is generally 0.82-0.95, specific heat at 10,000-11,000 kcal / kg or so. Composed primarily of hydrocarbons, containing another portion (about 0.1-4%) of sulfur and trace amounts of inorganic compounds.

Injector nozzle close

When the heavy oil is mixed with the fuel injected into the cylinder, due to the rapid and complete combustion can not, will form a larger carbon particles, which resulted in clogging of the nozzle.
4, the dangers of paraffin
Fuel (diesel) itself, viscosity, viscosity decreased as the temperature becomes greater, namely: low temperatures fuel (diesel fuel) poor fluidity.

Paraffin oil composition containing a low temperature, the wax is easily crystallized, will lead to the fuel flow variation. The lower the temperature, the more wax crystal clear, even the formation of crystalline networks will eventually lead to the fuel loss of mobility.
At low temperatures, the mobility of bad fuel, fuel can pass tubing and filters, and filter clogging the pipeline would result in reduced or even interrupted fuel supply, the engine does not work properly (difficult to start) and even flame (not start) .

5, the dangers of sulfur

The sulfur in the fuel generated in the combustion acids, it is expressed as:
(1) to accelerate the deterioration of the oil
(2) within the body surface corrosion
High sulfur content diesel fuel in the combustion easy to generate a strong acid, and strong acidic substances can cause and exacerbate corrosion of metal parts and engine wear. For example, combustion chamber and exhaust system of the engine caused by corrosion gas, is readily coagulated into sulfuric acid (H2SO4), attached to the cylinder and on the various parts of the exhaust system, a strong liquid metal corrosion. And this will also promote the formation of carbon and carbon resulting harden. These carbon attached parts, will increase mechanical wear.
Generated in the combustion process of fuel sulfur trioxide, to capture some of the dust particles floating, when faced with the lower surface temperature of the metal parts, it will bring to capture the dust adhering to the metal surfaces together and continue Some live in floating dust adsorption to form deposits. Once the deposited layer is formed, the thermal conductivity of the metal where the efficiency decreases rapidly, rapid temperature rise, leading to high temperature corrosion of the metal. Therefore, the content of sulfur in diesel is not too high.

Second, you do not know the little details, diesel management right and wrong
Error 1, loaded drums dirty

Cause of error: re-clean diesel will give dirty.

Correct: drums, to clean

Correct: drums, to clean

Right way:
Funnel, oil drums should be cleaned.

Error 2, when refueling drums down, and scroll to the front of the machine.

Cause of error: tipped and then scroll to the bottom of the barrel originally precipitated water and impurities and diesel mixed together.

Right way with a small carts next to the machine

Right way with a small carts next to the machine

Right way:
Care should be taken 24 hours will precipitate diesel, next to the machine with a small carts to carry out refueling.

Error 3, refueling pipe input with dirty diesel

Error 3, refueling pipe input with dirty diesel

Error 3, refueling pipe input with dirty diesel

Cause of error: dirt along with diesel fuel into the tank.
Right way:
Tubing together in a clean filter material (eg stockings) for fuel filter impurities may be exclusion from the outside of the tank.

Error 4, the drums placed high, insert the tubing for fuel
Cause of error: unsafe practices, if there are dirty drums substances, dirt, because of the pressure of the tubing along the tubing into the tank.
Right way:
No ordinary tubing, and use a hand pump to refuel equipment is a good solution. (Note: The hand pump in the commercially available)

Third, the daily management of the fuel Precautions
We bought the diesel required for construction machinery and equipment, must not ignore the drums management issues, correct storage of these fuels to avoid a lot of unnecessary failure.
1, prior to purchase, to control the incoming quality; purchase, to strengthen the management of the library


(1) Control supply channel, do not buy mixed with water, sand, oil fuel poor.
(2) placing the fuel in a centralized location, we must pay attention to the fire ban smoking.
(3) placed in the open air fuel barrel, fell to the ground as far as possible be placed sideways, and pay attention to the bucket cover (cloth, plastic sheeting available) to prevent the fuel drums will be mixed with rain.
(4) Place the fuel barrel, as must be placed standing, pay attention to the fuel side of the pad into the bottom of the barrel stuff, so one side can tilt bucket to place the water flowing into the hole in the top of the barrel
(5) for a half tank of fuel oil barrels, as a horizontal flat placed in a manner lying on the ground, so that the barrel of fuel oil fuel oil out of a position higher than the position of the hole to prevent air suction.

2, construction machinery operations, according to the ambient temperature of choosing the right fuel to prevent fuel from freezing.
Diesel diesel grades that the freezing point of 0 ° C to lose fluidity diesel No. 0 diesel oil, and so on. Use, we should be more then the temperature used to select the appropriate grades. Grades should be lower than for general use temperature 5-10 degrees Celsius, in order to ensure that the diesel engine is working properly.

3, suggest the majority of users, immediately after the end of each day to fill the fuel
Immediately after the end of each day to fill the fuel, and every day before starting from the oil-water separator tank and discharged water.
You can fill up the tank inside the air expelled, or moisture in the air will condense mixed with fuel oil.
Clean water separator, as is the discharge of water deposited on the bottom of the reservoir, debris.
4, according to the provisions of genuine replacement fuel filter maintenance time

Each machine has the “Maintenance Manual”, which for machine operation and maintenance are the most detailed descriptions and comments. We can carefully study, due to various reasons, many car owners, the driver did not even read the “Maintenance Manual”, relies entirely on the master professor or maintenance of machinery based on my experience, this is actually a great waste. Suggest that you find when buying a car with a “Maintenance Manual”, on the cab for the driver’s reference.
“Maintenance Manual” where there will be on the engine fuel filter replacement time considerations. We suggest that you use genuine original fuel filters, is, in fact have said thousands of times, and not repeat them here. Figuratively speaking, a filter is like drinking milk, good milk price is expensive but the quality is good, cheap melamine may have. You want the engine to live longer, it is recommended to use genuine, if you just care about the cost of money, please ignore this paragraph.

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