Precautions For Removing The Injector

The fuel supply system is an important part of the diesel engine and belongs to the heart of the diesel engine, and the fuel injector is the most important part of the system. Whether the technical state of the injector is good or not will directly affect whether the diesel engine can work normally. As one of the three precision parts of a diesel engine, the injector is different from other parts, and has very strict requirements on its processing and assembly accuracy, and cannot be disassembled at will. Otherwise, it will not only affect the service life, but also easily cause damage to the precise coupler of the injector, thus affecting its service life.

1. Disassembly method of fuel injector

1 When disassembling the fuel injector, for the fuel injector whose sealing gasket is a cone gasket, the cone gasket must be removed first before loosening the tight cap of the fuel injection nozzle, so as to prevent the needle valve body of the fuel injection nozzle from being clamped by the cone gasket. As the tight cap of the fuel injector rotates at the same time, the positioning pin of the needle valve body of the fuel injection nozzle is broken, and even the positioning pin of the fuel injector housing and the needle valve body of the fuel injection nozzle is cracked. For fuel injectors with positioning pins on the housing, before loosening the tight cap of the fuel injection nozzle, the fuel injection pressure adjustment screw should be unscrewed to prevent the fuel injection nozzle pair from shifting outward under the pressure of the fuel injection nozzle spring. , resulting in a large torque on the positioning pin, causing the positioning pin to break, and even causing the pin hole to crack.

After removing the injector, be sure to remember the serial number of the cylinder where it is located, and do not make a mistake. Since both the needle valve and the nozzle body are ultra-precise components, extra care must be taken when handling the injector assembly so that there is no damage in the slightest. In addition, it should be noted that after removing the injector assembly from the engine, first clean the outside of the assembly, and then gradually test it on the injector hand pump test bench to carefully check the initial injection pressure, spray quality and oil leakage. If it is confirmed that the quality is good after inspection, it is not necessary to dismantle it.

2. Disassembly points of the injector

There are certain procedures and special tools for the disassembly and assembly of the fuel injector. Therefore, the disassembly and assembly staff must follow certain procedures and use special disassembly and assembly tools for disassembly and assembly. . When disassembling the fuel injector, first disassemble the upper part of the fuel injector, loosen the pressure regulating screw to fasten the nut, take out the pressure regulating screw, pressure regulating spring and ejector rod, and clamp the fuel injector upside down in the workbench vise. On, loosen the needle valve body to fasten the nut, and take out the needle valve body and needle valve. If it is difficult to remove the needle valve body from the tight cap, first pull out the needle valve, then place a wooden block on the head of the needle valve body, and tap the needle valve body lightly. If the needle valve is difficult to remove from the needle valve body, it can be taken out after soaking in gasoline for a while. This method is still difficult to solve. You can use hand pliers to put a cloth on it, clamp the tail of the needle valve, turn it and pull it out gently. If the needle valve and the needle valve body are stuck, you should consider replacing the new coupler.

It should be noted that when the injector is decomposed, care must be taken to protect the surface of the needle valve from being scratched by hard objects. After the disassembly is completed, the gasket of the injector should be kept together with the original injector body, and the conical gasket between the injector and the seat hole should also be placed with the original injector body. . When assembling, pay attention to the alignment of the needle body and the pin. After the parts of the injector have been cleaned and dried and passed the inspection, they should be installed in a clean place without dust, and the work surface should be highly clean.