Inner Wall of Generator Set Valve Guide

As the core component of the valve distribution mechanism and intake and exhaust system of the generator set, valve guide failures still occur due to the complex working environment. Severe wear on the inner wall of the valve guide of the generator set can lead to excessive consumption of lubricating oil, so it is extremely important. Today, Jiangsu Starlight Power Equipment Co., Ltd. will introduce the solution and fault phenomenon of severe wear on the inner wall of the valve guide of the generator set.

(1) Troubleshooting and replace with a new generator set valve guide. During assembly, use a hammer and mold to insert the conduit. While striking, continuously rotate the mold to ensure that the conduit is not misaligned. When the air valve stem moves up and down in the assembled guide tube, it should not become astringent, and the valve seat should be quickly and accurately seated and in good contact with the valve seat, thereby providing a good sealing effect. After reinstallation, the machine was tested and smoke exhaust and lubricating oil consumption were normal.

(2) Fault phenomenon: A certain type of bulldozer equipped with Cummins N series diesel engine experienced overheating and rapid consumption of lubricating oil during operation. Start the diesel engine and discover that the exhaust pipe emits blue smoke during stable operation.

(3) Fault diagnosis and analysis: First, remove the air filter and start the diesel engine. It was found that the smoke exhaust phenomenon did not change, indicating that the blue smoke phenomenon was not caused by insufficient intake air. Preliminary judgment shows that the diesel engine is burning lubricating oil. Considering that the bulldozer has been used for a long time, it may be due to excessive wear of the cylinder liner or damage of the piston ring and bow of burning oil. Therefore, when the diesel engine cylinder head was removed, it was found that there was unfinished lubricating oil on the top of the piston, and there was a lot of carbon accumulation in the combustion chamber. Then, by observing the wear of the cylinder wall, it was found that the wear of the cylinder wall was not severe. After taking out the piston, the piston ring was not installed reversely, and the piston ring groove, piston skirt, cylinder wall and piston ring were straightened, and no abnormality was found. Therefore, the possibility of lubricating oil entering the combustion chamber from both the piston and cylinder liner has been ruled out, and it is highly likely that the burnt lubricating oil enters the combustion chamber along the valve guide of the generator set. Remove the intake and exhaust valves, and upon inspection, it was found that the valves moved up and down in the guide tube, while also slightly swaying radially. There was residual lubricating oil on the valve stem and valve chamfer cone.

After measurement, it was found that the valve guide pipe diameter of some generator sets is too large. Wipe the inner wall of the valve guide with cotton yarn, and through careful observation, it is found that the inner wall of the generator set valve guide is severely worn. From this, it can be inferred that the phenomenon of burning lubricating oil is caused by excessive wear of the generator set valve guide. It is speculated that it may be due to the tightening and astringency of some valve stems when passing through the generator set valve guide during maintenance and replacement. The repairman polished them, resulting in a larger pipe diameter. Moreover, it damages the thread of the oil storage, causing the lubricating oil in the rocker arm chamber to easily flow into the combustion chamber along the inner wall of the generator set valve guide or valve stem through the valve head during diesel engine operation, resulting in abnormal consumption of lubricating oil and abnormal exhaust smoke from the exhaust pipe.

Starlight Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.