Iron filings are produced in the hydraulic system of small excavators. This is a common phenomenon in some excavators, so let's talk about it. 
Iron filings were found in the hydraulic system of a small excavator. The tank and pipes must be cleaned quickly, and a strong magnet must be placed in the hydraulic tank. There may be iron filings on the radiator and other places. Even if the radiator is replaced, cleanliness cannot be guaranteed. How to deal with it? I want to install a magnet filter on the front end of the big pump. I don't know if it works? 
The approximate method to determine the iron filings in the hydraulic system of a small excavator:

The manufacturing cylinder is shiny because it does not lose its luster at low speeds. Hair is a pump or motor bearing created by high-speed rotation and passivation.

Judging the situation:

If it is a relatively large iron filings and is easily found in the fuel tank, then the cylinder may be damaged.

If there is no major problem with the filter element of the hydraulic system, the valve and pump itself may not produce iron filings. However, radiators and hard tubes are also possible. Of course, this will only happen when new cars or new parts are replaced. 
The pressure on the return line is low, and a filter element with higher precision can be selected. If it is not in the fuel tank, it seems that there is no relationship between the magnetic properties. Generally, the flow rate of the hydraulic oil in the pipeline is very high, and it is difficult for general magnets to absorb it. 
1. The engine water temperature is very high. After removing the thermostat, the small hole under the thermostat seat blocks the cork to prevent recirculation of hot water. 
2. The gear pump separates the sides to form a vacuum as the suction port. The volume on the extrusion side becomes smaller, and pressure is generated as a discharge port. The back of the 3-shaped valve plate always faces the discharge port. The valve plate generates an axial force squeezing the gear under the pressure of the pressurized oil to enhance the seal. It also has the effect of automatically compensating the pressure after wear. 
3. The smallest core of the driver's handle is mainly used for micromanipulation. 
4. Individual parts are often blocked. Check whether the connecting pipe is caused by internal peeling.

5. The center of the distributor lever spring is thinner than the outer ring, and the outer ring should be the stroke buffer at the end of the stroke. The intermediate sleeve limits the stroke of the rod.

6. Approximate judgment of iron filings: 1. The light is cylindrical, and its luster is not lost due to its low speed. 2. The iron filings are produced by pumps or motor bearings because of high-speed rotation and dullness.

7. The second pilot pressure is normal, but the action is slow. The hammer should consider whether the spool in the pilot handle is dirty to limit its stroke, so that the stroke is reduced (even if the operation is maximum), the pressure is sufficient, but the flow is insufficient. If the force on the valve stem is not enough, the valve stem is not open enough, and the related actions will be very slow.

8. Joint action is slow or motionless. The relevant pilot secondary pressure is lower than 20KG.