The cause of abnormal noise in the piston pin
The main reasons for the abnormal noise of the piston pin are as follows:
(1) The piston pin and the connecting rod bushing are worn out too much, and the fitting is severely loose. The main reason is due to poor lubrication. There is no oil hole on the connecting rod of the WD615 series engine. The lubrication of the piston pin and the bushing is performed by the lubricating oil nozzle spraying upward through the oil collecting groove of the small connecting rod. If the oil pressure is too low, the injection condition is not good, which will cause the piston. The pin and the connecting rod bushing are poorly lubricated, and the poor cooling of the piston due to poor injection also increases the wear of the piston pin and the connecting rod bushing. If the oil deteriorates and becomes thin, it will also cause wear and tear. Therefore, we must pay attention to the quality of the oil, it is best to change the oil according to the cycle, replace the oil filter.
(2) During the repair of the connecting rod bushing, the dimensional positioning is not accurate, the matching of the bushing and the connecting rod is not good, and the abnormality of the piston pin may occur. It must be installed according to the standard during maintenance so that the connecting rod bushing can be pressed under a certain pressure.