The Common Rail Engine Of The Excavator Cannot Be Started, The Solution Is Actually Very Simple!

The high-pressure common rail engine has relatively high requirements for the quality of the excavator's fuel, and the fuel quality determines whether the engine can work normally. Many owners like to add fuel from informal channels due to cost considerations. In the end, the excavator always fails.

Failure phenomenon

The problem was that a Doosan DX120 excavator

failed to start after it was turned off during normal operation. When the engine is started, the exhaust pipe does not exhaust smoke, and the instrument panel displays the fault code E001076-16.

Cause Analysis

The equipment fault code is E001076-16, and the query code display: Common rail pressure control error (IMF current control abnormality). Maintenance personnel use the detection tool to detect the fault code as P0254, and there is no historical fault code display.

According to the fault performance and fault code of the equipment, it is inferred that the cause of the equipment fault mainly involves the fuel system and high-pressure oil circuit, which need to be checked one by one.

Inspection process

1. First, check the fuel system pipeline of the engine, and there is no blockage or leakage. Check that the fuel system is not blocked from the low-pressure oil circuit, release the impurities at the bottom of the fuel tank, drain the oil-water separator, and pump the oil at the filter element of the hand oil pump.

2. Check that the electrical plug of the engine is not loose, the ECU plug is not loose, and the resistance of the common rail pressure sensor is not abnormal.

3. The jamming of the common rail relief valve will cause abnormal engine common rail pressure. Check that the relief valve is normal.

4. Check the IMF plug and wiring harness, and measure the IMV resistance, and there is no abnormal condition.

5. Use the detection software to observe that the pressure at startup is 91bar, which is abnormal. The maintenance personnel inferred that there is a jam inside the solenoid valve of the metering unit. Checking the solenoid valve of the metering unit does not find any problems.

6. Restart the test engine, but the engine still can't start, the fault code is still displayed.

7. Replace the fuel filter element and exhaust, and then start the test run to eliminate the fault, and the fault code of the instrument panel of the equipment is also eliminated.

cause of issue

Because of the poor quality of the fuel used by the owner, the fuel filter element was blocked, and the common rail pressure of the fuel metering unit could not be established due to abnormal fuel supply, resulting in failure to start.

Fault handling

Replace the fuel filter to exhaust the fuel system, clean the fuel tank, and inform the user to add fuel from a regular gas station

Summarize

Fuel is equivalent to the food of the engine, so it is said that "the disease is imported from the mouth." People will get sick if they eat unclean food, and the use of low-quality fuel in the engine will cause various failures and shorten the service life of the engine.

All aircraft owners must pay attention to fuel use in daily life, especially high-pressure common-rail engines, and must be filled with high-quality fuel from regular channels.

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