After a Komatsu pc430-8 excavator is started, the working device can realize various actions, but the main pump makes abnormal noise.
The pc430-8 hydraulic pump of Komatsu excavator maintenance has abnormal noise, which is generally caused by:
1. The oil suction filter element is blocked, causing the main pump to empty;
2. The main pump is empty due to insufficient hydraulic oil;
3. Air is mixed in the oil suction pipe;
4. The internal wear of the main pump causes abnormal noise during the operation of the main pump.
According to the analysis of abnormal sound of pc430-8 hydraulic pump repaired by Komatsu excavator, it is believed that the excavator pump is empty or the oil circuit is mixed with air, so first adjust the working device to the oil level detection position, and check that the oil level of the hydraulic oil tank is below the low level of the oil standard, which belongs to the position of oil shortage.
After asking the driver, he learned that the sealing ring of the high-pressure oil pipe leading to the stick cylinder without rod cavity had been replaced due to oil leakage during operation, but the oil level had not been checked in time after replacement.
Therefore, first fill the hydraulic oil tank to the standard oil level, and the test machine shows that the abnormal noise is still present although it has been reduced;
Then, after exhausting the main pump through the exhaust valve of the main pump, it was found that the abnormal noise still existed, indicating that the noise could not be completely caused by the empty pump.
The final result is that the oil level is not checked in time after replacing the seal, resulting in insufficient hydraulic oil and empty suction of the main pump; When the oil mixed with air flows through the main pump, the slipper cannot float or float sufficiently at some moments, resulting in the failure to form a good lubricating oil film between the slipper and the swashplate, causing the slipper to wear, and finally causing abnormal noise during the operation of the main pump.
Troubleshooting for abnormal sound of pc430-8 hydraulic pump repaired by Komatsu excavator:
First, the oil suction filter element and the oil return filter element of the hydraulic oil tank of Komatsu excavator were checked, and it was found that the oil suction filter element turned black and there was oil sludge, while there were brown metal particles on the oil return filter element, so the above filter element was replaced; Considering that there are brown metal particles on the oil return filter element, the oil of the main pump was discharged and checked, and brown metal particles were also found; At the same time, during the disassembly and inspection of the main pump, it was found that there was no damage to the piston, port plate, swashplate, etc., while the sliding shoes were worn. After replacing it, it was assembled in strict accordance with the requirements, the hydraulic system was cleaned and the oil was changed. When the test machine was started again, the abnormal noise disappeared and the fault was eliminated.
