If the generator set suddenly changes its load, you may hear a thudding sound around your body. This is primarily caused by abnormal friction between the crankshaft connecting rod journal and the connecting rod bearing. The main reasons for this abnormal friction are excessive clearance between the crankshaft journal and the connecting rod bearing, as well as local jumps.
The principle and maintenance inspection methods of this sound are identical to those of the main shaft and its bearing sleeve. The sound is clearly audible from the front cover of the generator set. It originates from the meshing gears inside the front cover.
Excessive wear on the meshing gears, with excessive gaps between them, leads to normal gear engagement without such noise. The solution is to open the front cover and utilize it. Inspect the gear engagement and adjust with lead sheets or paint. If the gear gaps are too large, replace the gears regularly. A sound of impact from the cylinder top is heard.
As the number of valves decreases, the impact noise increases. The primary cause of this sound is the impact between the cylinder and piston. The main reason for this situation is insufficient valves leading to the piston reaching the top dead center, resulting in a strong impact force between the cylinder and piston at high speeds. At this point, the generator set is very weak, and the bearing capacity of the mechanical load is significantly reduced.
The specific method to eliminate such faults is to sequentially increase the actual refrigeration capacity of each cylinder to the upper limit, compress the cylinder downwards, check for any gaps between the actual refrigeration and the cylinder, and then re-adjust the cylinder.
