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

① 柴油不清潔，高壓油管內有雜質，力出寞了噴曲器針閥偶件的磨損，使針閥偶件關閉不嚴，燃燒室內高壓燃氣反竄，燒壞針閥偶件。此外，噴油器調壓彈簧、挺桿等 零件上的臟物通過噴油器挺桿移到了噴油器針閥上部，或油路上用于防止漏油的棉繩、鉛絲經高壓油管進入噴油器，都會使針閥偶件卡死。

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機溫過高噴曲器冷卻不良，造虎地閥偶件卡死。而供油時間過遲、冷卻水道水垢過多或堵塞、水泵葉輪端面磨損、發動機長期超負荷等又會使發動機過熱。

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出抽閥磨損，使噴油器停止噴油時出現滴油現象，以致使噴曲嘴燃焦積炭，發生卡死的故障。

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噴曲壓力過低，造成燃燒室內高壓燃氣反竄；

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

⑤噴油器安裝時，漏裝墊片或墊片破壞，造成漏氣，引起噴油器局部溫度過高而卡死。

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，如氣缸蓋上噴油器安裝孔與噴油器配合過緊，針閥體與氣缸蓋上的安裝孔間隙過小，氣缸蓋噴油器安裝孔加工過深等。

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、噴油嘴卡死的修理方法：

2、 Repair method for stuck fuel injection nozzle:

先 將卡死的噴油嘴放入柴油或機油內加溫，然后取出用布包住，再用手鉗夾緊針閥并慢慢活動，將針閥從針閥體內取出。將少量清潔機油滴在針閥體內，使針閥在針閥 體內反復活動，直至針閥能在針閥體內活動自如。如針閥的密封面有燒傷的痕跡，應當用研磨膏進行研磨。研磨時要注意掌握研磨膏用量和研磨時間。將清洗干凈的 鐘閥偶件裝上噴油器，并調整好噴油壓力后即可重新使用。

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.