The reasons for the low hydraulic pressure of the two busy excavators are:

1. The gap between the crankshaft and bearings is too large

When using a hydraulic excavator for a long time, the matching gap between the crankshaft and connecting rod bearings gradually increases, and the hydraulic pressure of the oil wedge that has not yet formed also decreases. According to the measurement, when the gap increases by 0.02mm, the hydraulic pressure decreases by 0.02Mpa. You can grind the crankshaft and select the corresponding size of connecting rod bearings to bring the fit clearance back to technical standards.

2. Insufficient oil output from two busy oil pumps

When the gap between the oil pump shaft and the bushing, as well as the gap between the gear end face and the pump cover, is lateral or radial. Exceeding the allowable value due to wear may lead to a decrease in pump oil volume and lubrication pressure.

3. Temperature too high

The cooling system may be large and may not function properly, the excavator may be overloaded for a long time, or the fuel supply speed of the fuel injection pump may be too slow, resulting in overheating of the body. The oil pressure decreases due to a large loss. You will need to remove the scale from the cooling system pipes and adjust the oil supply time to enable the excavator to operate at rated load.

4. Busy oil pumps at both ends stop

If the drive gear of the oil pump and the fixed pin of the drive shaft come off, or if the mating key comes off and the oil pump sucks in foreign objects and the pump oil gear gets stuck, the oil pump will stop and the hydraulic pressure will become zero. Replace damaged pins or keys, and install filters on the suction port of the oil pump.

The above is the reason for the low hydraulic pressure of the two busy excavators. I hope it can be helpful to you!