Because the fuel injector works under high temperature and high pressure for a long time, it is easy to cause faults such as loose sealing, oil dripping and poor atomization. These faults may cause serious faults such as black smoke, insufficient power, abnormal noise of combustion system, cylinder pulling and piston top burning. However, in the field troubleshooting, how to confirm that the above faults are caused by the problem of fuel injector is the key to troubleshooting. Based on many years of practical work experience, the manufacturer of gas generator set has obtained the following basic methods to confirm that the fuel injector has quality problems:

１、首先直接观察燃气机的排烟情况，如果喷油器存在上述问题，柴油机排烟应该是：起动时冒白烟、全负荷工作时冒黑烟并伴随有功率不足等问题。

1. First, directly observe the smoke exhaust of the gas engine. If the fuel injector has the above problems, the smoke exhaust of the diesel engine should be: white smoke when starting, black smoke when working at full load, accompanied by insufficient power and so on.

２、单缸灭火法：

2. Single cylinder fire extinguishing method:

起动燃气机中低速运转，然后逐缸松开高压油管，当松开某缸高压油管后，柴油机排气烟色有明显变化时，则说明该缸喷油器或柱塞／出油阀有问题。

Start the gas engine at medium and low speed, and then loosen the high-pressure oil pipe cylinder by cylinder. When the high-pressure oil pipe of a cylinder is loosened and the exhaust smoke color of the diesel engine changes significantly, it indicates that there is a problem with the injector or plunger / outlet valve of the cylinder.

３、直接观察法

3. Direct observation method

拆下排气管，起动燃气机低速运转，可以直接看出某缸排气烟色不正常，即可初步判断该缸喷油器或是柱塞／出油阀有问题。

Remove the exhaust pipe and start the gas engine to run at low speed. It can be directly seen that the exhaust smoke color of a cylinder is abnormal, and it can be preliminarily judged that there is a problem with the injector or plunger / outlet valve of the cylinder.

４、在确认某缸喷油器或柱塞／出油阀有问题后，可以取出该缸喷油器，在喷油器试验器上确认该喷油器是否有问题。

4. After confirming that there is a problem with the injector or plunger / outlet valve of a cylinder, take out the injector of the cylinder and confirm whether there is a problem with the injector on the injector tester.

５、如果经过试验确认喷油器有问题，则必须按要求修复或更换喷油器（嘴）。

5. If there is a problem with the fuel injector after the test, the fuel injector (nozzle) must be repaired or replaced as required.

６、如果现场附近没有喷油器试验器，作为临时措施，可以在柴油机上检查一下喷油器是否有问题。具体做法是：将排气烟度相反的两个缸的喷油器调换使用，起动燃气机并观察排气烟色，如果调换使用后，原来不冒烟的缸烟度增大，则说明该喷油器有问题。如果两个缸的烟度都增大，则说明该缸（原来冒黑烟）的柱塞／出油阀可能也有问题。、

6. If there is no injector tester near the site, as a temporary measure, check whether there is a problem with the injector on the diesel engine. The specific method is: exchange the fuel injectors of two cylinders with opposite exhaust smoke, start the gas engine and observe the exhaust smoke color. If the smoke of the cylinder that did not smoke increases after exchange, it indicates that there is a problem with the fuel injector. If the smoke of both cylinders increases, there may also be a problem with the plunger / outlet valve of the cylinder (originally emitting black smoke)

７、如果试验确认喷油器没有问题后，则需要进一步检查喷油泵。

7. If the test confirms that there is no problem with the fuel injector, further check the professional fuel injection pump.