High-Quality 4HK1 Engine Assembly | Kyotechs Excavator Parts

The way to prevent wear includes regular maintenance, using the right hydraulic oil, keeping the hydraulic system clean, and avoiding overload operation.

Connecting the terminals of the same polarity of each battery together is called parallel connection. Its characteristics are: the voltage is the same as the voltage of a single battery, and the current flowing out is equal to the sum of the currents flowing out of each battery. (The voltage remains unchanged, and the current increases). Connecting the opposite-polarity terminals of each battery in sequence is called series connection. Its characteristics are: the total voltage is the sum of the voltages of each battery, and the current flowing out is the same as the current flowing out of each single battery. (The current remains unchanged, and the voltage increases).

Digging powerlessness can be divided into two situations: one is digging powerlessness, the engine does not hold back, and the load feels very light; the second is digging powerlessness, when the boom or dipper stick is extended to the bottom, the engine is seriously held back or even stalled.

①, digging powerlessness but the engine does not hold back. The magnitude of the digging force is determined by the output pressure of the main pump, and whether the engine holds back depends on the relationship between the oil pump absorption torque and the engine output torque. The engine does not hold back, indicating that the oil pump absorption torque is small and the engine load is light. If the working speed of the excavator is not obviously abnormal, the maximum output pressure of the main pump, that is, the system overflow pressure, should be checked in particular. If the overflow pressure measurement value is lower than the specified value, it indicates that the overload overflow valve setting value of the hydraulic circuit of the mechanism is incorrect, resulting in premature overflow of the mechanism and powerlessness. The machine can be adjusted by turning the adjustment screw.

②, digging powerlessness, engine holding back. The engine holding back indicates that the absorption torque of the oil pump is greater than the engine output torque, causing the engine to overload. This fault should first check whether the engine speed sensing system is normal, and the inspection method is similar to the engine inspection method described above. After the above detailed inspection and troubleshooting, the engine speed sensing system will resume normal function, the engine stalling phenomenon will disappear, and the digging force will return to normal.

First, park the excavator on a flat, safe surface, shut off the engine, and release the system pressure. Then, open the drain plug on the hydraulic tank to drain the old oil. Replace the filters, refill with new hydraulic oil, start the engine, run the system to expel air, and check the oil level.