عنوان مقاله [English]
The purpose of this paper is troubleshooting, adjusting and analysis of a useful diesel engine fuel injector from common rail system with experimental and laboratory investigations. In the new diesel engines, the fuel common rail system has an important contribution to increase efficiency and improve engine performance. The injector as one of the most important and advanced components in the common rail system has numerous failures in test engine. For this purpose, different parts of a sample injector are introduced. Based on the results of 200 injectors and step back from the client to identify potential failure modes it is cleared that three sets of magnets, valve and needle are the weaknesses and vulnerable parts of an injector. To the experience of researchers in the most time, adjusting the Shim thickness of the injector is the easiest and most effective way to repair and reset of it. To achieve the optimal placement of shims in a test rig, various thicknesses of shims was placed in the injector. Penetration of the spray, spray cone, droplet size and performance of the motor in vehicle test were evaluated to achieve the optimal placement of the shims. The results show that in each case the parts to fix it, there is an optimum thickness Shim that it are certified in the both injector flow test and the actual engine test.