What Causes Piston Pin Noise?

[TaliaAnn]

General causes of piston pin noise are as follows: Causes of piston pin noise: Excessive wear and clearance between the piston pin and the small end bushing of the connecting rod. Excessive clearance between the piston pin and the piston pin bore. Low oil pressure, insufficient oil splashing, and poor lubrication effect. The piston pin lock ring falls off, causing the piston pin to move freely. The piston pin breaks. Methods for determining piston pin noise: Perform a cylinder-by-cylinder fuel cut-off test. Conduct an engine throttle shake test. Control the engine speed within the most obvious range, then perform a cylinder-by-cylinder ignition cut-off test. If the noise is more obvious, it can be determined as piston pin noise. If the noise is very severe and increases with higher engine speed, perform an ignition cut-off test at the speed with the most noise. If the noise does not disappear but becomes more chaotic, it can be determined that the clearance between the piston pin and the bushing has increased due to wear.