How to maintain an infrequently used diesel generator set?
(1) The fuel injector assembly (referred to as the fuel injector) must be carefully cleaned when disassembling and assembling, especially the newly replaced fuel injector assembly must be carefully and thoroughly cleaned.
(2) Sometimes, after a fuel injector with good spray quality is disassembled, cleaned and reassembled, the spray quality deteriorates, and it cannot even be used any longer. This is because the needle valve cone of the used fuel injector and the needle valve body of the fuel injector have been worn out, but the sealing ring is still good. The mating position is broken (needle valve turns). Therefore, the fuel injector should not be disassembled blindly without the fuel injector tester testing and confirming that it must be disassembled.
(3)For injectors with cone gaskets, such as Dongfeng Chaochai 102 and 105 series diesel engines and Hangqifa 6120 series diesel engines, the cone gasket should be removed first before unscrewing the tight cap of the injection nozzle. To prevent the needle valve body of the fuel injector from being clamped by the taper and rotate together with the tight cap of the fuel injector, causing the positioning pin of the needle valve body of the fuel injector to break, and even positioning the needle valve body of the fuel injector with the needle valve body of the fuel injector Pin hole cracked. For injectors with positioning pins on the casing, such as FAW Dachai and FAW Xichai 110 series diesel engines,and Dongfeng Chaochai 102 series diesel engine injectors, before unscrewing the tight cap of the injector, first unscrew the fuel injection pressure Adjust the screw to prevent the injector assembly from moving outward under the pressure of the injector spring, causing
a large torque to the positioning pin, breaking the positioning pin, and even cracking the pin hole.It is sometimes difficult to take out the broken part of the positioning pin from the positioning pin hole of the injector housing. At this time, it is often necessary to install only one positioning pin or no positioning pin. Generally speaking, it is not appropriate to install only one positioning pin on the needle valve body of the fuel injector in case of emergency. Because when only one positioning pin is installed, the fuel injector cap is tightened, and the needle valve body of the fuel injector may rotate around the positioning pin. In this way, the needle valve of the fuel injector and the tappet hole of the fuel injector housing are easily misaligned. Once misaligned, the force of the injector tappet acting on the needle valve tail rod can easily produce a certain radial force component. In light cases, the needle valve is prone to block when it moves up and down in the needle valve body, and it may barely maintain normal at the time of debugging, but the potential hidden dangers cannot be ignored. In severe cases, the needle valve moves up and down in the needle valve body and becomes long, and oil dripping may occur during debugging. For the needle valve body without ring groove, the oil passage hole of the needle valve body of the injector and the oil passage hole of the injector housing may be greatly misaligned when the positioning pin is not installed. Although it will not affect the combustion of diesel oil, the oil passage hole The reduction of the cross-sectional area will have a certain impact on the fuel injection quantity.
(4) For those with needle valve lift adjustment screws, such as the injectors of Tiandong 146 series diesel engines, the lift adjustment screw should be unscrewed before assembling the injector assembly, so as not to install the injector When tightening the tight cap of the fuel injector, parts such as the adjustment screw of the needle valve lift of the fuel injector are deformed. In addition, when installing the coupling of the fuel injector into the tight cap of the fuel injector, the flange of the needle valve body of the fuel injector is missing and The positioning pin on the tight cap must be aligned, and the nozzle plate and the needle valve body should never be separated.
(5) If the surface roughness of the two sides of the locking nut of the fuel injection pressure adjustment screw is different, such as the fuel injector of Luoyang Yituo 4125 series diesel engine, the side with the smaller surface roughness value should be attached to the fuel injector housing so that it can be effectively contacted The area is large, the braking effect is good, the ability to prevent the screw from loosening is strong, and the locking is reliable.