The main reason for the weak operation of the excavator engine is a problem with the fuel system. The characteristics of the fault are:
The engine idling is normal. After the load is applied, it appears to be weak, the engine sounds dull, and the engine is easily turned off. The troubleshooting is as follows:
1. First turn on the hand oil pump, there is no air in the system, and it works normally. Then, after replacing the fuel coarse and fine oil filters, the engine works basically normal during small load leveling operation, but it is still abnormal under heavy load operation. In this regard, some people think that the high-pressure oil pump has insufficient oil supply. After analysis, it is considered to be a failure of the oil circuit, so the oil pipe between the filter element and the oil pump is removed for inspection, and it is found that the rubber in the pipe is aging. At the same time, the small filter in the hollow bolt of the pipe head is blocked. From this, it was confirmed that due to poor oil supply, throttling caused insufficient oil supply, which caused the excavator to work weakly. After replacing the oil pipe and cleaning the hollow screw, the work returned to normal.
2. The excavator works normally under no load, but it emits black smoke when digging soil, and the work is weak.
Inspection method: first check the fuel supply system, the result is normal, indicating that there is no problem with the engine itself; after observation, it is found that the exhaust pipe has more carbon deposits, so it is considered that the exhaust resistance is too large, causing power decline and black smoke. After opening the muffler, the work basically returned to normal after the carbon deposit was removed, but there was still a black smoke phenomenon. After careful observation, the vacuum indicator of the air filter element was red, indicating that the filter element needs to be cleaned or replaced, but after replacing several new filter elements, The engine still emits black smoke, and the vacuum indicator of the air filter element is still red. At this time, the air intake is not smooth, so I looked out along the air intake and found that the coarse air filter mesh has been blocked by debris such as catkins. After that, the engine operation returned to normal.
