Injector Maintenance And Repair

The injector should be inspected and adjusted once every 700 hours. If the opening pressure is lower than the specified value of 1Mpa or the carbon deposit at the head of the needle is serious, the needle valve should be unloaded into the clean diesel oil and scraped with carbon chips. The fine steel wire should be used to clear the spray hole. The injection pressure difference of each cylinder of the same machine must be less than 1 Mpa. Then do the oil seal test, that is, the injection pressure reaches 18 Mpa, let it drop to 17Mpa by itself, and its return time is not less than 10 s. Diesel fuel is not allowed to flow from the cone or the injector head is wet during the test. In addition, the sprayed oil bundle must be foggy with a crisp squeak, and the holes of the porous injector should also form a bundle of mist. The fog cone angle of each type of injector can be checked by standard injectors.

       In order for the fuel injected into the cylinder of the injector to be completely burned in time, it is necessary to periodically check the oiling time of the oil pump. If the fuel supply time is too early, the vehicle will have difficulty in starting and knocking the cylinder; if the oil supply time is too late, the exhaust will emit black smoke, the machine temperature will be too high, and the fuel consumption will rise.
Injector needle valve coupler has high precision and the orifice diameter is very small. Therefore, the clean diesel oil of the specified grade must be selected strictly according to the seasonal changes, otherwise the injector will not work normally. When mixing, prevent mixing with rain or snow and avoid adding oil in a dusty environment. To maintain the diesel filter on time, the filter oil and the oil in the fuel tank are often drained to prevent the intrusion of dust and sand and increase the wear of the needle valve.

      Do not collide with other hard objects when cleaning the needle valve coupler, or drop it to the ground to avoid bruising and scratching. When replacing the needle valve coupler, the new coupler should be placed in the 80C hot diesel oil for about 10 s. After the anti-rust oil is fully dissolved, the needle valve is twitched back and forth in the valve body in the clean diesel oil. Net, in order to avoid the failure of the needle valve to stick to the needle valve due to the melting of the rust preventive oil during operation. Needle valve couples must be replaced in pairs and are not interchangeable.

      If a large amount of air bubbles or oil droplets are seen when the high pressure pipe joint is loosened, the needle valve is stuck in the open state, and the compressed gas generated when the cylinder is compressed is reversed to the high pressure oil pipe through the injector. At this time, touch the high pressure oil pipe by hand. If the pulsation is not felt or the pulsation is weak, it means that the needle valve has been stuck. The needle valve should be unloaded for grinding and debugging. If the adjustment fails after the restoration, another new product should be replaced.