• Final Drives motor

If you don’t take a straight line, how is the excavator walking? How to deal with it?

Due to maintenance or operation reasons, many users' excavators will have the problem of final drive motors (divided into the left or rightward of the walking track), which seriously affects the work efficiency. If we encounter the excavator in the work, we will have a deviation. Phenomenon, how to find the cause and eliminate it?

Let us first understand what causes the excavator to run off?

1. The center rotary joint seal is damaged.

If the central rotary joint fails to replace the filter element of the hydraulic oil in time, the bypass valve on the filter element may be opened, and the hydraulic oil may be directly filtered into the sliding surface of the center rotary joint due to unfiltered oil, so that the seal ring on the filter is damaged. When the machine is running, the speed of the running oil on the two sides is different due to the leakage of the pressure oil on one side, and the result is that the machine is running away. The method of elimination is to replace the center rotary joint oil seal; replace the hydraulic oil and filter element.

2. The dirt enters the balance valve in the parking brake oil circuit on the side of the excavator.

3. The final drives safety valve leaks oil.

4. The dirt traps the balancing valve of the final drive system.

5. The main valve spool of the excavator is malfunctioning.

6. The travel suction valve on the deflection side of the excavator is damaged.

7. The degree of track tension is different.

8. The plunger of the pump flow regulator of the oil pump is stuck.

9. The output pressure of the running proportional valve is too low.

Knowing these reasons, let's analyze it, how can we fix it.

If the track sag causes a deviation, we should check whether the tension of the two tracks is the same. Support the two crawlers separately and check the amount of crawler sinking. The distance between the maximum and the horizontal line on the chassis is within the standard range (typically 320-340mm for pavement, 340-380mm for loach pavement, and 380mm for gravel and snow).

Check that the pilot pressures of the front and rear pumps are consistent from the dashboard.

The high-pressure oil pipes of the traveling motor are interchanged from the center joint, and if the fault phenomenon has changed during the test,

Then it can be ruled out that the right traveling motor is faulty.

Otherwise, the right travel motor is faulty.

The travel motor should be disassembled for inspection.

Find out the cause of the failure.

4The 4 oil pipes for the left and right running oil between the main control valve and the center joint are exchanged.

The obstacle phenomenon has changed, and the center joint is faulty. Otherwise, the center joint is faulty. It should be disassembled and found out.

The cause of the obstacle.

5 Check the spool of the left and right travel control valve and find that the spool is flexible in the valve body and there is no damage.

Therefore, the control valve can be eliminated.

6 When the two main pump regulators are interchanged, the test results show that the fault of the walking deviation also changes, so that it can be judged.

The fault is on the regulator, otherwise the fault should be on the hydraulic main pump.

7 When disassembling the regulator, it turns out that the O-ring on the spool has been aged and damaged, causing the spool to move.

Flexible, it is impossible to adjust the swash plate angle normally, thus making the rear pump displacement smaller and the walking speed slower.

When driving, it turned to the right.

8 Clean the pump regulator, replace the O-ring, and when the test machine is installed, the fault has disappeared.

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9249 S.Broadway #200-204

Highlands Ranch, CO. 80129

United States

1(877) 774-9372