18 Olil seals – examination and renovation 油封 - 審查和更新

18 Olil seals – examination and renovation 油封 - 審查和更新

1 the crankshaft oil seals from one of the most critical parts in any two-stroke engine because they perform the dual function of preventing oil from leaking along the crankshaft and preventing air from leaking into the crankcase when the incoming mixture is under crankcase compression.

1曲軸油封是一個最關鍵的部件在任何二衝程發動機，因為他們執行雙重職能，防止機油洩漏至曲軸箱和防止正在壓縮中的油氣洩漏進入變速箱。

2 Oil seal failure is difficult to define precisely, although in most cases the machine will become difficult to start, particularly when warm,The engine will also tend to run unevenly and there will be a marked fall-off in performance, especially in the higher gears. This is caused by the intake of air into the crankcases which dilutes the mixture whilst it is under crankcase compression, giving an exceptionally weak mixture for ignition.

油封的衰退故障是難以準確界定，儘管在多數情況下，機器會變得難以啟動，尤其是當(引擎)溫暖，新的引擎也將趨向運行不平衡，將有明顯下降抵消性能，尤其是在較高的齒輪。這是由於進氣口的空氣進入曲軸箱稀釋的混合物，而這是在曲軸箱壓縮，讓一個非常薄弱的混合物點火。

3 It is possible to renew the outer crankcase oil seals without difficulty, In this latter case, a replacement crankshaft assembly is the only way of ensuring a satisfactory crankcase seal.

有可能更新外曲軸箱油封不困難，但在後一種情況下，更換曲軸裝置是唯一能保證一個讓人滿意的曲軸箱密封狀態。

4 It is unusual for the crankcase seals to become damaged during normal service, but instances have occurred when particles of broken piston rings have fallen into the crankcases and lacerated the seals. A defect of this nature will immediately be obvious.

在正常保養維修前曲軸箱油封損壞，是不同尋常的一種狀況，但情況已經發生時，一種例子是破碎的活塞環落入曲軸箱撕裂了油封。這種性質的傷害，會立即讓人察覺。