Some engines in use will have a piston pin rattling fault. If the piston pin rattling serious damage to the piston pin bushing, increase the wear of the connecting rod shaft tile and crankshaft connecting rod journal, wear to the most serious, will pull off the piston pin or connecting rod top, break the cylinder block, do not wait to see.
The phenomenon of piston pin rattling fault is.
(1) the sound of the upper part of the cylinder, the sound is like two steel ball collision and issued by the "special" sound.
(2) after the engine temperature, the sound is generally not much change, individual sometimes more obvious, which is a major difference with the piston knock cylinder.
After the occurrence of piston pin rattling, you can use the following methods to determine.
(1) cylinder-by-cylinder oil cut-off test, after the oil cut-off, the sound is obviously weakened or disappeared, after the resumption of oil supply, will be more obvious. When the fault is serious to a certain extent, there will be a continuous continuous double sound, after the oil cut, the sound not only does not weaken or disappear, and will intensify.
(2) engine shudder throttle test. When shaking the throttle at a rapid rate, the noise is quite obvious, the cycle of the sound changes with the engine speed.
