1、 The main causes of fuel injection nozzle sticking are as follows:

① 柴油不清洁，高压油管内有杂质，力出寞了喷曲器针阀偶件的磨损，使针阀偶件关闭不严，燃烧室内高压燃气反窜，烧坏针阀偶件。此外，喷油器调压弹簧、挺杆等 零件上的脏物通过喷油器挺杆移到了喷油器针阀上部，或油路上用于防止漏油的棉绳、铅丝经高压油管进入喷油器，都会使针阀偶件卡死。

① The diesel oil is not clean and there are impurities in the high-pressure oil pipe, which force the needle valve coupling parts of the injector to wear out, so that the needle valve coupling parts are not closed tightly, and the high-pressure gas in the combustion chamber reverses and burns the needle valve coupling parts. In addition, the dirt on the pressure regulating spring and tappet of the injector moves to the upper part of the needle valve of the injector through the injector tappet, or the cotton rope and lead wire used to prevent oil leakage from entering the injector through the high-pressure oil pipe will cause the needle valve coupling to be stuck.

②机温过高喷曲器冷却不良，造虎地阀偶件卡死。而供油时间过迟、冷却水道水垢过多或堵塞、水泵叶轮端面磨损、发动机长期超负荷等又会使发动机过热。

② The temperature of the machine is too high, and the cooling of the spinneret is poor, and the coupling parts of the valve are stuck. However, too late fuel supply time, excessive scale or blockage of cooling water channel, wear of pump impeller end face and long-term overload of engine will make the engine overheat.

③出抽阀磨损，使喷油器停止喷油时出现滴油现象，以致使喷曲嘴燃焦积炭，发生卡死的故障。

③ The wear of discharge valve causes the fuel dropping phenomenon when the injector stops fuel injection, which causes the nozzle to burn coke and deposit carbon, resulting in stuck fault.

 

④喷曲压力过低，造成燃烧室内高压燃气反窜；

④ If the injection pressure is too low, the high pressure gas in the combustion chamber will reverse;

⑤喷油器安装时，漏装垫片或垫片破坏，造成漏气，引起喷油器局部温度过高而卡死。

⑤ When the fuel injector is installed, the missing gasket or the gasket is damaged, resulting in air leakage, causing the local temperature of the injector to be too high and stuck.

⑥零件制造方面的原因，如气缸盖上喷油器安装孔与喷油器配合过紧，针阀体与气缸盖上的安装孔间隙过小，气缸盖喷油器安装孔加工过深等。

⑥ The reasons for parts manufacturing are as follows: the injector mounting hole on the cylinder head matches the injector too tightly, the clearance between the needle valve body and the cylinder head is too small, and the machining of the injector mounting hole in the cylinder head is too deep.

二、喷油嘴卡死的修理方法：

2、 Repair method for stuck fuel injection nozzle:

先 将卡死的喷油嘴放入柴油或机油内加温，然后取出用布包住，再用手钳夹紧针阀并慢慢活动，将针阀从针阀体内取出。将少量清洁机油滴在针阀体内，使针阀在针阀 体内反复活动，直至针阀能在针阀体内活动自如。如针阀的密封面有烧伤的痕迹，应当用研磨膏进行研磨。研磨时要注意掌握研磨膏用量和研磨时间。将清洗干净的 钟阀偶件装上喷油器，并调整好喷油压力后即可重新使用。

First put the stuck nozzle into diesel oil or engine oil for heating, then take it out and wrap it with cloth. Then clamp the needle valve with a pair of pliers and move it slowly to take out the needle valve from the needle valve body. Drop a small amount of clean oil into the needle valve body to make the needle valve move repeatedly in the needle valve body until the needle valve can move freely in the needle valve body. If there are burn marks on the sealing surface of the needle valve, the grinding paste should be used for grinding. When grinding, pay attention to master the amount of grinding paste and grinding time. Install the cleaned bell valve coupling on the injector and adjust the injection pressure before reuse.