The piston rings of diesel generator sets are affected by high temperature, high pressure, and reciprocating motion during long-term use, which can exacerbate wear. When the wear reaches a certain limit, the elasticity of the piston ring begins to decrease, and the end gap, side gap, and back gap also gradually increase, weakening the sealing effect on the combustion chamber.

一、柴油機運行時，打開加機油口蓋觀察冒煙情況，若有冒煙現象，則逐缸斷油，若發現冒煙減輕或消失，響聲也消失，則說明是活塞環槽磨損過甚或活塞環斷裂，應及時維修。

1、 When the diesel engine is running, open the oil filler cap to observe the smoke situation. If there is smoke, cut off the oil cylinder by cylinder. If smoke is reduced or disappears, and the sound also disappears, it indicates that the piston ring groove is worn or even broken, and it should be repaired in a timely manner.

柴油發電機組活塞環異響診斷與處理方法

Diagnosis and treatment methods for abnormal noise of piston rings in diesel generator sets

二、若斷油試驗響聲沒有變化，而用一字旋具抵著缸蓋部位，感覺有明顯的振動，則是活塞環碰撞氣缸磨損處的缸肩而發出的響聲。此時應重新修整氣缸，以免活塞環斷裂。

2、 If there is no change in the sound during the fuel cut-off test, but there is a noticeable vibration when using a flat screwdriver to press against the cylinder head, it is the sound made by the piston ring colliding with the shoulder of the worn cylinder. At this point, the cylinder should be reconditioned to avoid piston ring breakage.

三、在熱機檢查時，可從噴油器安裝口處注入少量機油，轉動曲軸，再裝回噴油器發動柴油機，若短時間內響聲減弱或消失，則是活塞環與氣缸壁密封不良。若注入機油后，仍從加機油口冒煙或更甚，則可確診為活塞環對口（各道活塞環的開口間隙安裝在同一方向上，安裝時，相鄰兩活塞環的開口間隙應錯開120度-180度）或活塞環卡在環槽內失去彈性，對此應進行維護，清除積炭。

3、 During the hot engine inspection, a small amount of engine oil can be injected from the installation port of the fuel injector, the crankshaft can be turned, and then the fuel injector can be reinstalled to start the diesel engine. If the noise weakens or disappears in a short period of time, it indicates poor sealing between the piston ring and the cylinder wall. If smoke or even more is emitted from the oil filling port after injecting engine oil, it can be diagnosed as piston ring alignment (the opening gaps of each piston ring are installed in the same direction, and the opening gaps of adjacent piston rings should be staggered by 120 degrees to 180 degrees during installation) or piston rings getting stuck in the ring groove and losing elasticity. Maintenance should be carried out to remove carbon deposits.