將裝載機動臂落到底，然后啟動發動機，將動臂操縱桿置于下降位置，加大油門根據松開動臂缸大腔接口處的漏油情況即可判斷小腔油封的好壞。

1、若大腔接口處漏油比較多，則說明該缸油封密封不良或油封損壞；若松開處接口不漏油或漏油很少，則說明該動臂缸小腔油封密封性能較好。
If a large cavity at the interface more oil spills, then seal the cylinder seal or seal damaged bad; if release of the interface does not leak or spill rarely, then the better the small chamber of the boom cylinder seal sealing performance.
2、大腔油封損壞，就會造成升起的動臂自動下落，其判斷方法與小腔油封判定方法相反。也可用此法來判斷裝載機的翻斗缸或轉向缸的某一缸油封以及非對稱式液壓缸的某一腔油封的密封情況。
Large cavity seal is damaged, it will cause a rise in the boom automatically whereabouts, their judgment determination method and the small cavity seal opposite approach. Can also use this method to determine the loader tipping cylinder or steering cylinder and a cylinder seal asymmetric hydraulic cylinder seal a chamber sealed case.
3、原來未更換轉向機、轉向閥總成之前，雖然轉向油路壓力高，但因轉向閥磨損內漏較大，加上轉向機間隙較大，故用舊轉向機、轉向閥總成時反而合適，前輪不發擺；更換新件后，因轉向機間隙變小，轉向閥內漏也減少，從而使轉向時油路反應過于靈敏，出現前輪發擺現象。
Not replaced before the original steering, the steering valve assembly, although turning the oil pressure is high, but the steering valve leakage wear larger, with a larger machine steering gap,so the old steering gear, but proper steering valve assembly , the front wheel does not send pendulum; after replaced with new parts, because the gap becomes smaller steering, steering valve leakage is reduced, so that the steering response when the oil is too sensitive, appeared the front hair swing phenomenon.