What is the reason for the black smoke from the excavator engine
The reason why the engine emits black smoke is called a stubborn disease is largely because many aircraft owners can only wait for the engine to emit black smoke one by one but are helpless. Even if it is repaired at a high price, there will be repeated situations
The crux of the problem is that there are many faults that can cause black smoke. If there are omissions in the troubleshooting process, even if the situation improves at that time, it will bury the foreshadowing of recurrence Today, engineers will summarize and share the causes of the black smoke fault! With this secret script, the machine operator can repair the excavator himself!
What is the reason for the black smoke from the excavator engine
Black smoke analysis
There are two main reasons for the black smoke from the engine frequently encountered by the owners during the construction:
1、 The reason of the engine itself II. The reason of the load carried by the engine. First, analyze the reason of the engine itself
The black smoke emitted by the engine means poor combustion without any reason. In fact, it can be summed up as poor combustion, including the load reasons to be described later
Cause analysis
A. Insufficient or insufficient air
B. Poor fuel atomization and poor oil quality affect the combustion
C. Engine aging or early wear of individual components
D. Timing, fuel injection advance or lag (direct injection engine)
Troubleshooting of black smoke from excavator engine:
1. The air filter element is dirty or blocked, affecting the quality of the air, causing the air in the combustion chamber to be dirty and causing black smoke
2. There is leakage in the high-pressure gas pipeline, and the pipeline behind the turbocharger, such as intercooler, connecting rubber pipe, steel pipe, pipe hoop, etc., will also affect the insufficient air volume and emit black smoke during combustion
3. The turbocharger is damaged, resulting in insufficient air volume, and there will also be oil passing through the intercooled combustion chamber, resulting in black smoke or blue smoke
4. The fuel is dirty and contains many impurities, or the wrong fuel. Check the carbon deposit on the exhaust chimney
5. The filtering accuracy of the fuel filter element is not enough, resulting in poor filtering effect and dirty fuel combustion chamber, resulting in black smoke
6. The high-pressure oil pump is worn, the efficiency is reduced, and the fuel pressure provided is insufficient, resulting in insufficient fuel quantity, which will also affect the combustion effect
7. The wear of fuel injection nozzle is generally caused by water and other impurities in the fuel. Once worn, the fuel injection effect will be affected and the atomization will be poor. The injection pressure can be detected
8. Carbon deposits in the fuel injection nozzle and cylinder affect the atomization effect of fuel injection, resulting in insufficient combustion. In addition to black smoke, white smoke will also appear
9. The exhaust valve is worn and the seal is not tight. The compression ratio in the combustion chamber will be reduced. The combustion is definitely bad and black smoke will be emitted
10. The aging or wear of piston ring is mainly caused by the influence of gas ring and poor sealing effect between piston ring and cylinder liner, which reduces the compression ratio and causes poor combustion
11. If the timing is not correct, adjust the advance device (direct injection machine). When the piston reaches the top dead center of compression, the delayed or advanced injection will definitely be the fuel that cannot achieve the best atomization effect, so it will inevitably lead to poor combustion effect and black smoke
12. The common rail pressure is not enough (electronic injection) or the common rail pressure sensor sends an error signal to the engine computer board. It is the same as the direct injection high-pressure pump. In this case, the engine will generally display an alarm
13. There is leakage in the high-pressure pipeline, which is the same as the wear of the high-pressure pump
14. The sealing in the cylinder of the glow plug and the fuel injector is poor, and the high pressure will leak, resulting in the reduction of the air-fuel mixture ratio in the combustion chamber. The oxygen in the mixture is insufficient, and black smoke will be emitted during combustion
summary
Therefore, although the fault phenomenon is a single black smoke, the root cause is at least a dozen fault causes. If the troubleshooting direction is wrong or the troubleshooting is not thorough enough, it is very easy to miss. This is also the reason why the owners complain that they spend a lot of money to repair the fault, but they often recure.
