What is the diesel engine fuel supply advance angle

Diesel engine fuel supply advance angle: -- The difference between diesel engine and gasoline engine is: diesel engine is compression ignition type, gasoline engine is ignition type.

When the piston of the diesel engine goes up, the fresh air in the cylinder is compressed and its temperature is increased to a combustion temperature of about 570 °, and the injector is injected in advance before the piston reaches the upper dead center 5 7 ° to ensure better combustion of the fuel; Because: first, the fuel is injected into the cylinder through the injector and starts in a torch-shaped state, which cannot be evenly distributed in the cylinder; 2. The fuel is injected into the cylinder through the injector, and there is a process of mixing, friction and heating with the air in the cylinder to ensure the atomization of the fuel and the air; 3. In addition, according to the characteristics of diesel combustion, diesel combustion generally has an ignition period, a burst period and a retardant period.

Therefore, in order to ensure the combustion quality and reduce the hazard of aftercombustion, the diesel engine must establish an injection advance angle. --Hope it helps.

Because the diesel engine adopts the compression ignition type, and it is also direct injection in the cylinder (so it will not be injected after the piston is almost to the top dead center like the gasoline engine), the diesel engine is generally injected when the crankshaft angle is 50-70 degrees before the compression stroke, so this angle is called the fuel injection advance angle.

Diesel engines are fueled by compression, also known as "compression-ignition engines". The principle is as follows, when the cylinder intake is completed, the piston begins to run from the bottom dead center to the top dead center, compresses the diesel, and when the cylinder pressure reaches the diesel ignition point (the general pressure of No. 0 diesel is 8MPa), the diesel begins to burn. We know that the starting point of gasoline combustion is at the ignition gap of the spark plug, while the diesel engine does not have an ignition system, so the starting point of combustion is uncertain, and we can only give an approximate ignition pressure of 8MPa.

Since this pressure is very short when the engine is working, the ignition angle is also very small (I remember that it was 5-7 degrees, I don't remember how much).

The principle of diesel engine must be understood by you. It is to compress the mixed air to cause spontaneous combustion of diesel fuel.

This feed advance angle refers to a certain angle of the crankshaft of the machine before reaching the top dead center when the piston compresses the air upwards. In other words, if the diesel engine wants to completely mix the clean air and diesel that is sucked in, it needs to supply fuel at this angle. In this way, when the mixture is completely compressed, the oil and gas can achieve a more ideal mixing ratio.

In order to achieve better economy and power.

In a word, it is to mix the oil and gas components.

Remove the high-pressure oil pipe, turn the outlet of the connection end with the fuel injector into a horizontal tightening oil pipe, and then slowly rotate the flywheel in the clockwise direction, observe the moment the oil just comes out of the high-pressure oil pipe outlet stop rotating the flywheel, and check the position of the scale and mark on the flywheel in time is the angle of the oil supply advance angle. Generally, the advance angle of fuel supply is 15 degrees - 19 degrees, and the advance angle of fuel injection is 7 degrees - 9 degrees.

When adjusting the advance angle of oil supply, the fuel injection pump needs to be removed and the gasket between the pump body and the gear chamber cover is increased or decreased. When the gasket is removed, the oil supply advance angle increases, and when the gasket is added, the oil supply advance angle decreases.

Hello 1Remove the high-pressure tubing.

Remove the valve cover.

When the intake valve is closed and then shaken about 180 degrees, you can see that the flywheel overlaps with the advance angle engraving line on the fuselage, and the other line is the top dead center engraving line.

The crankshaft is reversed at this point.

Half a turn, and then turn the crankshaft forward, pay attention to observe the oil level fluctuation of the oil injection pump outlet valve port, and see whether the flywheel engraving line is aligned with the body engraving line. Deviation from the front, indicating that the oil supply time is early, the thickness of the oil pump seat cushion needs to be increased, and the thickness of the oil pump seat cushion needs to be reduced at the back.

Summary. Under normal circumstances, the fuel supply advance angle of diesel engine can improve the output power and fuel economy of diesel engine. The advance angle refers to the angle at which the fuel injection pump is injected ahead of the piston to reach the top dead center, that is, the time when the fuel enters the combustion chamber in advance.

The proper advance angle allows for more adequate combustion, improved thermal efficiency, and reduced fuel consumption and emissions. However, if the advance angle is too large, it is easy to cause knocking and damage the engine. Therefore, the advance angle of diesel engine fuel supply needs to be adjusted according to the specific engine design and working conditions to ensure normal operation and high efficiency and energy saving.

Under normal circumstances, the fuel supply advance angle of diesel engine can improve the output power and fuel economy of diesel engine. The advance angle refers to the angle at which the fuel injection pump is injected ahead of the piston to reach the top dead center, that is, the time when the fuel enters the combustion chamber in advance. The proper advance angle allows for more adequate combustion, improved thermal efficiency, and reduced fuel consumption and emissions.

However, if the advance angle is too large, it is easy to cause knocking and damage the engine. Therefore, the advance angle of diesel engine fuel supply needs to be adjusted according to the specific engine design sail and working conditions to ensure normal operation and high efficiency and energy saving.

Can you tell us more about that?

It can provide output power and fuel economy.

How to adjust the fuel supply advance angle of the diesel engine in the absence of data, The fuel supply advance angle adjustment method of the diesel engine: (1) Remove the high-pressure oil pipe of the fuel injection pump 1 cylinder, one person shakes the crankshaft, when it is about to reach the position of the 1 cylinder fuel supply advance angle, it is necessary to slowly shake the crankshaft, one person stares at the oil outlet oil surface of the oil outlet valve of the 1 cylinder, when the oil level just moves upward, stop shaking the crankshaft, and check whether the oil supply advance angle on the flywheel or the crank damping pulley is on the corresponding finger (for the convenience of future inspection, In this case, a pair of timing marks can be added on the coupling and pump casing). (2) first remove the high-pressure oil pipe of the four cylinders of the fuel injection pump, then remove the gas release bolt on the fuel injection pump, install a special adapter that is processed according to the need, and then install the dial gauge to tighten, rotate the crankshaft, the percentage representation number will change accordingly, when the crankshaft turns to a certain angle, the percentage representation number will remain unchanged, at this time the dial gauge is zeroed, and then rotate the crankshaft to a cylinder top dead center (0 °).

Look at the readings of the dial gauge. Because the fuel injection pump is fixed on the diesel engine cylinder block through three bolts on the triangular fixing plate, the fuel injection pump can only be adjusted after the three nuts are loosened: the fuel injection pump body is rotated at a certain angle against the rotation direction of the camshaft, and the fuel supply advance angle increases; Otherwise, it decreases.

Summary. 1. If the timing gear assembly mark is correct, you need to unscrew out the fastening nut of the three bolts on the high-pressure oil pump, and then remove the high-pressure oil pump; 2. If the oil supply is too late, reduce the gasket, increase the gasket too early, determine the thickness of the gasket according to the angle of advance and lag, and generally increase or decrease the thickness of the gasket, and the advance angle of the oil supply will change by about 3°;

1. If the timing gear assembly mark is correct, you need to unscrew out the three bolts on the high-pressure oil pump and tighten the nut in a large way, and then remove the high-pressure oil pump; 2. If the gasket is reduced if the oil supply is too late, and the gasket is increased too early, the thickness of the gasket is determined according to the angle of advance and lag, and the gasket of the thickness of the block is generally increased or decreased, and the angle of oil supply is changed by about 3°;

3. If all the gaskets are removed, the oil supply advance angle is still too clear and late, according to the degree of delay, the oil pump body can be shaved off by 1 2mm of metal with a lathe, and then the method of increasing or decreasing the gasket can be adjusted to the correct and appropriate oil supply advance angle. It's very simple, first loosen the bolt of the large pump connecting block, and then turn the camshaft of the large pump to adjust, adjust to the appropriate angle, and then tighten it. Xie Jiezheng is a brief thanks.

The oil supply advance angle is large, and the difficulty of cold car start is still small.

Hello, generally speaking, the diesel engine is difficult to start, if it starts, there is obvious white smoke, it must be too late for the fuel supply angle. The advance angle of oil supply refers to the angle of the crankshaft corresponding to the top dead center of the piston at the time when the fuel injection pump starts to supply oil to the cylinder. The oil supply advance angle is too small, the oil supply time is delayed, and even the highest compression pressure point in the cylinder (that is, after running to the compression top dead center), which will cause the diesel fuel to be difficult to ignite, incomplete combustion, difficult to start, insufficient line power, black smoke from the exhaust pipe and other symptoms.

Summary. Hello, remove the high-pressure oil pipe, turn the outlet of the connection end with the injector into a horizontal tightening oil pipe, and then slowly rotate the flywheel in the clockwise direction, and observe the moment the oil just comes out of the outlet of the high-pressure oil pipe to stop rotating the flywheel, and check the position of the scale and mark on the flywheel in time is the angle of the oil supply advance angle.

Hello, remove the high-pressure oil pipe, turn the outlet of the connection end with the fuel injector into a horizontal tightening oil pipe, and then slowly rotate the flywheel in the clockwise direction, observe the moment the oil just comes out of the outlet of the high-pressure oil pipe, stop rotating the flywheel, check the scale on the flywheel in time and the position of the mark is the angle of the oil supply advance angle. Open the calendar.

Hope mine can help you.

Whether it is supplied with oil from the advance angle scale or with the top dead center scale.

Oil single-cylinder diesel engine fuel supply time is to observe the degree on the flywheel scale to check whether the fuel supply time is correct, different models of diesel engine fuel supply advance angle is not the same as the group sale, simply put, the oil supply advance angle refers to the piston to the top front distance seepage and oil supply, the specific adjustment method is as follows: Remove the high-pressure oil pipe, install the high-pressure oil pipe outside so that the oil outlet is facing up. Slowly turn the flywheel to observe whether there is oil coming out of the outlet of the high-pressure oil mill open tube.