When the injection pump plunger is stuck, it will affect the normal operation of the governor and easily lead to the engine flying fast. If it is not handled in time, it will cause serious accidents.
1. The plunger is bent. Due to the lack of attention in the transport, storage and assembly of the plunger pair, the plunger is slightly bent, and the phenomenon of card issuance occurs in the work, which should be replaced in time.
2. The plunger encounters mullah injury. Because the plunger assembly is not cleaned, or impurities enter between the plunger pairs, the assembly is not paid attention to, the plunger will touch the mullah injury, resulting in the plunger hair stuck. Therefore, the assembly should be carefully installed, do not hurt the plunger, and clean the plunger pair to prevent impurities from entering the plunger pair.
3. The sleeve positioning screw is too long. If the positioning screw of the plunger sleeve is too long or the washer is not installed when installing the positioning screw, the sleeve will be pushed out and the sleeve will be offset, causing the plunger to snap. If the positioning screw is too long, you can file the right amount of short, do not forget to install the washer when installing the positioning screw.
4, pump base uneven. Due to the uneven base or dirt at the shoulder of the plunger sleeve installed in the pump body, the assembly accuracy of the sleeve is affected, and the assembly of the oil pump plunger is skewed, resulting in the plunger sticking. The way to check the uneven pump body is to pull the injection pump from the body, connect the low-pressure oil circuit and open the tank switch, so that the pump body is filled with diesel, and wipe the outside of the injection pump. If oil leakage is found at the roller, it indicates that the base of the pump body is uneven, resulting in diesel leakage. You can use an old plunger sleeve, coat the shoulder with abrasive sand, put it into the pump body, rotate and knock the sleeve continuously for grinding, and then assemble and check whether there is oil leakage.
5. The storage time of the new plunger is too long. The storage time of the new plunger is too long, which is easy to cause oil loss and oxidation reaction, so that the plunger rusted, and the assembly is not cleaned, resulting in the plunger hair stuck in the work. In this case, the plunger pair should be immersed in kerosene or diesel oil for a period of time, and then turn and repeatedly pump the plunger to grind each other until the plunger pair is flexible and carefully cleaned before assembly.