Komatsu Equipment Troubleshooting And Repair

In the daily use of excavators and bulldozers, problems such as abnormal hydraulic systems, slow traveling speed, and black smoke from the exhaust are often encountered. In this article, MyMROmarts helps you better understand the working principles of excavators and bulldozers, improve maintenance efficiency, and extend the service life of Komatsu equipment through detailed analysis of these Komatsu equipment failures.

 

Fault 1: Hydraulic system oil temperature is too high

 

Excessive oil temperature in the excavator hydraulic system is a common problem that can lead to reduced system performance or even damage to key components. A customer reported that replacing the oil radiator did not resolve the issue. After careful analysis, our experts found that the temperature difference between the inlet and outlet of the oil radiator was large, indicating that the hot oil failed to pass through the oil radiator. After checking the system diagram, it was suspected that there was a problem with the check valve entering the oil radiator. After disassembling and inspecting the one-way valves, it was found that the spring of one of the check valves had broken, causing a large amount of return oil to bypass the oil radiator and flow back to the fuel tank. After the customer replaced a new one-way valve, the hydraulic system returned to normal operation, and the oil temperature was controlled.

 

Fault 2: The car warms up slowly and the main safety valve is worn

 

During the warm-up process of the excavator, if the speed is found to be abnormally slow, this is caused by the wear of the main safety valve. Our experts shared a maintenance experience and successfully solved the problem of slow heating of the excavator by grinding and repairing the main safety valve. The normal operation of the main safety valve is very important for the smooth operation of the entire hydraulic system. It is recommended that you regularly inspect and perform necessary maintenance to ensure the normal operation of Komatsu equipment.

 

Fault 3: The reason for the slow speed of the single-sided crawler

 

The single-sided crawler speed of the excavator is slow, but the crawler speed can increase when rotating at the same time. This may be caused by insufficient flow supplied to the travel motor plunger pump. Our technician explained that when the excavator performs other actions at the same time, it is equivalent to increasing the flow rate of another plunger pump. Therefore, checking whether the flow rate supplied to the traveling motor plunger pump is normal is very important to solve the problem of the slow track speed of the excavator.

 

Fault 4: The single-sided crawler track can only move forward but not backward.

 

If the single track of the excavator can only move forward but not backward, this is caused by the overload relief valve core in the traveling motor being stuck. For the safety of the system, two overload relief valves need to be installed in the traveling motor. When one of the valve cores is stuck in the overflow position, it will cause a loss of system pressure and affect the backward movement of the crawler track. During maintenance, the overload relief valve needs to be inspected and cleaned to confirm that it can operate normally.

 

Fault 5: The track cannot move and the excavation arm is weak

 

The excavator performed normally when it started working, but suddenly one of the tracks could not move and the excavating arm was weak. This was caused by the unclean hydraulic oil circuit and tiny dirt blocking the damping hole in the safety valve. In this case, MyMROmarts recommends that you remove the safety valve and clean it to remove the blockage of the damping hole, thereby restoring the excavator to normal operation.

 

Fault 6: The engine emits black smoke and stalls, making walking unable

 

There may be multiple reasons for the excavator engine to emit black smoke and become unable to walk. Experts from MyMROmarts suggest that you first check whether the supercharger is working properly. If it is not holding the car, the piston ring may be damaged. In addition, problems with the air intake system, whether the air filter is dirty, whether the supercharger is locked, etc. can also cause the engine to emit black smoke. It is recommended that you make a preliminary judgment on whether your excavator needs major repairs based on the color and condition of the smoke.

 

The above is the analysis and maintenance experience of some common faults of Komatsu excavators. As heavy machinery, excavators require frequent maintenance and repairs to resolve faults in a timely manner to ensure the safe and efficient operation of heavy equipment.