Special overhaul case of Komatsu excavator emitting black smoke
Cause analysis and maintenance process of Komatsu excavator emitting black smoke
A Komatsu excavator is digging in the reservoir. It has only been more than 6000 hours. After the excavator is started, when the engine is accelerated, the black smoke is particularly large. When the engine is idling, the black smoke is not obvious.
Komatsu excavator emits particularly large black smoke. The possible reasons are:
1. The air intake system of the excavator engine is blocked and insufficient, resulting in black smoke.
2. There is leakage in the diesel and gas circuits of the excavator.
3. The air inlet pressure sensor of the excavator is damaged.
4. The intake pressure of excavator engine is abnormal and the pressure value is low.
The Komatsu excavator emits black smoke and is overhauled:
1. After the construction site, start the test run first, and the engine will emit particularly large black smoke when accelerating, and there is no black smoke when idling. Check the oil circuit and air circuit of the whole excavator, and no abnormal leakage is found.
2. Check the air intake system of the engine to ensure that the pipeline is free of blockage and insufficient air intake. Connect the pressure gauge to detect the intake pressure of the engine, and it is found that the intake pressure is 1 when the engine is idling; When the engine is accelerating, the intake pressure is less than 1, so it is concluded that the low intake pressure of the engine may cause the excavator black smoke.
3. The intake pressure sensor was disassembled for inspection. It was found that the color of the metal connector of the sensor plug-in was different from that of the normal one, and the color was the same as that of the excavator. It was suspected that the paint was sprayed during painting. Replace a new pressure sensor, start it, retest the intake pressure, and the pressure value is 1 when accelerating. The fault is solved.
