2010-02-27
Fault phenomenon:
1. Two unitsDigging machineAlmost at the same time (one in the morning and one in the afternoon), there was a slow operation fault of the entire machine. Among them, the movement of the upper arm is the most obvious, and the on-site test shows that the upper arm rises in 5.69 seconds, which is nearly 3 seconds slower than the standard (2.7-3.3).
2. The engine experiences a deceleration phenomenon
·At low speeds, the boom rises and overflows, causing the engine speed to drop to around 600 revolutions per minute. Normally, the speed should increase
·When the boom rises and overflows at high speed, the engine speed drops by about 50 revolutions per minute. Normally, the speed should increase
·When the suction pressure of the high-speed boom overflows, there are only over 170 points, and normally it should be around 220KPa
·When the upper arm rises, there is a decrease in horsepower (around 60-26)
·Hydraulic and electrical systems are functioning normally, with no abnormal alarms
reason:
1. Due to twoKobelco excavatorBased on the condition that the same fault occurs within a short period of time, the following speculation can be made:
·Both vehicles experienced a decrease in engine speed, and due to the same construction site and the use of the same diesel fuel, it is speculated that there may be a malfunction in the diesel fuel circuit
·A decrease in horsepower indicates insufficient engine output. There may be two reasons:
One reason is the phenomenon of insufficient intake pressure, which may be due to a malfunction in the intake system, as the engine experiences such a reduction in horsepower during high altitude.
The second issue is the malfunction of the engine injector/SCV valve, which leads to insufficient fuel injection, resulting in insufficient engine output and reduced engine speed. This possibility is relatively high because both cars use the same diesel and the oil quality is poor.
Solution:
1. On site, transparent diesel pipelines were used to check for any leaks in the diesel oil circuit, and it was found that there were no leaks. On site replacement of the front and rear diesel filters resulted in an improvement in the speed drop at low speeds, dropping to over 700 revolutions per minute, while there was no significant improvement at high speeds. During the processing, it was found that the quality of the diesel was very poor. The filter element was swollen after only two or three days of replacement, and the appearance of the diesel looked slightly oily. Samples have been taken and are awaiting investigation.
2. All intake pipes, turbochargers, and intercoolers were checked and found to be normal, but the malfunction persisted even after removing the outer space for testing. Determine that there is no malfunction in the intake.
3. After discussion, everyone applies to the company for the replacement of SCV valves and fuel injectors for the entire vehicle. First, the SCV valve was obtained from the inventory vehicle and replaced with a test drive, but the problem was not resolved. Then, after the company parts arrived, they replaced the entire vehicle with fuel injectors for a test drive, and the entire vehicle returned to normal operation.
Send your inquiry directly to us
