“哐哐”响声从何而来□启明一台东风—１２型方向盘式拖拉机修理后，启动时机油压力正常，无冒烟现象，但发现有较明显的杂声，在靠近飞轮的一侧发出如敲盆子的“哐哐”声。熄火后检查：飞轮未与发电机相碰；上下平衡轴也未与连杆大头相碰。响声是由于飞轮螺帽未拧紧而发... Where did the noise come from? 启 明 After a DF-12 steering wheel tractor was repaired, the oil pressure was normal and no smoke was emitted at start-up, but more obvious noise was found and was emitted near the side of the flywheel Such as the raspberry “哐 哐” sound. After the flameout check: flywheel does not collide with the generator; up and down balance shaft has not collided with the bulkhead. The noise is due to flywheel nut is not tightened ...