4JA1、4JB1型发动机连杆轴承异响的早期诊断

Early Diagnosis for Abnormal Sound of Connecting Rod Bearing of Engine Model 4JA1 and 4JB1

4JA1和4JB1型高速柴油发动机分别匹配于五十铃（ISUZU）NHR54和NKR55系列客货两用汽车,它们使用了铜基合金镀覆表面的薄壁轴瓦,并与高精度轴颈表面配合。介绍了连杆轴承的工作条件、造成损坏的原因、早期异响的诊断以及具体的维修方法。

High speed Diesel engines Model 4JA1 and 4JB1 are matched with ISUZU NHR54 and NKR54 series pickups respectively. They use the thin wall bearing liner for which its surface is plated with the copper-based alloy and fitted with the high precision journal surface. The working conditions, the causes of failures, the early diagnosis for abnormal sound and the maintenance methods are described in this paper.