1, the fuel injector repair

In the long-term work, due to the erosion of high-pressure oil, mechanical impurities grinding and pressure spring seating and other joint role, will make the needle valve and the valve body with the surface of the wear and tear, Which caused the leakage before the fuel injection and oil after the phenomenon of oil, resulting in poor atomization, combustion is not complete, the smoke increased dramatically, coke serious. Therefore, the injector must be regularly maintained.

(1) disassembled to remember the cylinder of each injector

Remove the injector from the cylinder head, carry out a simple external cleaning, and then one by one disassembly, inspection, assembly, to prevent the same parts of different injectors in the assembly when mixed with each other. The specific steps are: first the injector nozzle hole clamped down on the vise, remove the pressure screw cap, pressure screw and spring cleaning. And then the fuel injector U-head fixed on the vise, loosen the occasional tightening screw sets, remove the injector even pieces, make the necessary cleaning after the following test.

(2) inspection is divided into visual inspection and sliding test

Visual needle and valve body with the surface must not have burning or corrosion phenomenon; needle valve needle can not be deformed or other damage. For the sliding test, the valve body should be tilted about 60 degrees, the needle out of about 1/3 of the stroke after the release, the needle should be able to rely on its own weight smooth decline; turn the needle position, repeat the above operation, if Needle valve is not in any position can be a smooth decline, you should replace the needle valve.

(3) assembly

Cleaning the body and its oil, the regulator spring, pressure screw part assembled together. Note that the pressure screw can not be screwed too tight, so that in the latter part of the performance check to facilitate exhaust and the overall cleaning. Will be available or replaced after the needle valve on the clean with a plastic pot filled with diesel, swimming valve back and forth to carry out a thorough cleaning. So that the fuel injector regulator part (should be below) fixed on the vise, the needle valve coupling according to the positioning requirements on the joint surface, and then tighten the occasional tightening Lo sets, and then the following performance check.

2, the performance of the injector check

Check the fuel injection pressure and atomization status of the Baotou North Mercedes-Benz accessories injector, and should be carried out on the injector’s tester. The tester consists of manual oil pump, Baotou North Mercedes-Benz accessories pressure gauge and storage tank and other components, the oil tank into the manual oil pump, after its pressurized high-pressure diesel into the injector and was mist spray.

When checking, loosen the pressure screw on the injector, install the injector on the tester, and press the handle on the tester repeatedly so that the injector and the high pressure tubing are completely filled with diesel. And then slowly press the handle, while observing the oil pressure gauge readings. When the reading begins to fall, it is the opening pressure of the injector, its value should meet the standard requirements.

Most of the adjustment method of the domestic model injector is realized by adjusting the preload force of the regulating spring by adjusting the pressure regulating screw. For the individual imported model, it is realized by changing the thickness of the gasket Pressed.