发动机的不正常声响,如敲击声和杂音可能来自多种部位,应仔细鉴定确认。 1.活塞敲击声活塞敲击声产生的原因如下: (1) 活塞敲击声的产生主要是由于气缸与活塞间隙不当造成的。气缸与活塞间隙过大,在活塞作功行程开始时活塞在气缸内摆动,活塞裙部撞击缸壁,产生敲击声。如果这种敲击声在冷态下(发动机刚刚起动) Engine abnormal sound, such as percussion and noise may come from a variety of parts, should be carefully identified to confirm. 1. Piston Percussion Piston percussion sound generated as follows: (1) piston percussion sound is mainly due to improper air cylinder and piston clearance caused. The gap between the cylinder and the piston is too large. When the piston starts to work, the piston swings in the cylinder, and the piston skirt collides with the cylinder wall to generate a percussion sound. If this rap sound in cold (the engine just started)