Common Rail Control Valve Assembly F00VC01052 for Injector 0445110036

Inspection and Maintenance of Diesel Fuel Injector

1. Faults caused by the tight cap of the fuel injector not being tightened

A diesel engine whose fuel injector was replaced during maintenance, when the fuel injection pressure was adjusted, it was found that the fuel injection pressure rose to 20 MPa and no fuel was injected, so the pressure regulating screw was loosened, suddenly there was a one-time fuel injection, and the injection speed was slow , The fuel injection sound is not crisp. Disassemble and check: the needle valve of the fuel injector slides freely, the steel ball in the ejector rod of the fuel injector is intact, the pressure regulating spring meets the technical requirements, and the oil inlet and outlet holes are unblocked. So reinstalled it again. As a result, the tight cap of the fuel injector was replaced, and the fault was eliminated. The cause of this failure is that the right angle shoulder of the tight cap pressing the oil nozzle is burned, which destroys the shoulder plane, making the shoulder plane not perpendicular to the axis of the tight cap. When the tight cap is tightened, the injector housing produces a small amount Inward shrinkage and deformation cause the needle valve of the injector to not slide freely, causing the needle valve to be stuck and the fuel injection to be abnormal. The burning of the shoulder of the tight cap is due to the failure to tighten the tight cap of the fuel injector when replacing the fuel injector during use. During use, the high-pressure gas in the cylinder infiltrates into the contact surface of the sealing shoulder for a long time, resulting in burning. . Therefore, when replacing the needle valve of the fuel injector, care must be taken to tighten the tight cap of the fuel injector