一是汽缸盖螺母未旋紧或汽缸垫损坏。转动曲轴时,如发现汽缸盖与机体的结合面处有漏气声,可能是汽缸盖螺母未旋紧,也可能是汽缸垫损坏。如是前者,应按要求旋紧;若是后者,当汽缸垫损坏不严重时,可用石棉线将损坏处补好,严重时更换新垫。二是进、排气门漏气。若气门间隙太小,关闭不严,需重新调整间隙。另一可能的原因是在气门密封锥面上有斑点,如生锈、积 First, the cylinder head nut is not tightened or cylinder pad damage. When turning the crankshaft, if there is air leakage at the joint surface between the cylinder head and the machine body, the cylinder head nut may not be screwed tightly, or the cylinder head gasket may be damaged. If the former, should be tightened as required; if the latter, when the cylinder liner damage is not serious, asbestos line damage can be replaced at a good replacement in severe cases. Second, into the exhaust valve leak. If the valve clearance is too small, lax closed, the need to re-adjust the gap. Another possible reason is that the valve seal cone spots, such as rust, product