Auto Parts Diesel fuel injector Nozzle DNOPDN112 fuel nozzle DN0PDN112 for diesel engine

The dismantling process of the injector nozzle pair 

1.1 Cleaning

Soak the injector nozzle to be repaired in light diesel oil for several hours, then take it out, and brush the surface with a fine copper wire brush to remove rust, oil and carbon deposits.

1.2 Use a special tool to clear the upper hole of the injector

Use a steel wire with a diameter of 1.5mm to grind the edge and dredge all the carbon deposits and dirt inside the oil inlet channel of the injector nozzle body.

Sharpen the reamer similar in shape to the oil cavity in the injector nozzle body, and remove all the carbon deposits and dirt in the oil storage room.

If the injector nozzle and the injector nozzle body stick together, use a special removal tool to remove the stuck injector nozzle. Do not use pliers to pull out the injector nozzle, or clamp the injector nozzle handle on the vise to knock it, to prevent some injector nozzles from being bent and breaking the injector nozzle handle and being scrapped. For the injector nozzle that is not easy to disassemble with special tools, it can be put into the engine oil and heated to about 150°C, and then taken out and disassembled while it is still hot.

1.3 Inspection

After cleaning, check all parts of the fuel injector, especially the injector nozzle pair, to determine whether to replace or repair. The cylindrical guide surface of the injector nozzle is blackened, and at the same time, the injector nozzle is stuffed into the injector nozzle and feels loose, which proves that the guide surface has a large gap. When in use, there must be a lot of oil return, and the oil pressure cannot be adjusted high. Trying to increase the oil pressure may cause the pressure regulating spring to fail, and the oil will not be sprayed out.

The valve line of the injector nozzle plays the role of controlling the fuel injection volume, maintaining a certain injection pressure and ensuring good pulverization of the fuel injection. If there are signs of damage, it is not sealed during use, and the pulverization of the fuel injection is poor or cannot be atomized. At the same time, there is dripping on the surface of the nozzle hole of the injector nozzle.

There are signs of unevenness and damage on the joint plane of the large end of the injector nozzle, which proves that it is not used well. If the defect is on the outer ring, the fuel will leak out during use; if the defect is on the inner ring, the fuel will leak to the oil return hole.

The cooperation between the injection hole of the injector nozzle body and the small head of the injector nozzle should not be too loose or too tight. If it is too loose, the pulverization quality will decrease, the pulverization will be less and the oil particles will be thicker, and the sound will not be crisp. If it is too tight, the fuel injection will form a line, the fuel injection will be silent, and if the fuel injection lasts too long, pulverization will easily occur.