Wear of Diesel Generator Fuel Delivery Valve and Its Solutions

The wear of diesel generator fuel delivery valves is a common issue that can significantly impact the performance and reliability of the engine. This article will delve into the causes of wear on different components of the fuel delivery valve, analyze the resulting effects on engine operation, and provide detailed methods for detection and maintenance to ensure the normal and efficient running of the diesel generator.

Causes of Wear on Diesel Generator Fuel Delivery Valve

The wear of the sealing cone of the fuel delivery valve is caused by the residual pressure between the delivery valve spring and the high-pressure oil in the high-pressure fuel pipe, which leads to the impact of the valve core on the valve seat sealing cone and the abrasion from impurities in the diesel fuel. In contrast, the wear of the pressure relief ring belt and the seat hole is mainly attributed to the abrasive action of impurities present in the diesel fuel.

Impacts Caused by Wear of Fuel Delivery Valve

When the sealing cone of the fuel delivery valve is worn, it will lose its sealing performance, resulting in irregular oil return in the high-pressure fuel pipe. This leads to a reduced and unstable residual pressure in the fuel pipe, and may even cause a decrease in fuel supply or a complete failure of fuel supply. At low speeds, this will cause uneven operation of each cylinder. Additionally, it will delay the injection time because more time will be required to build up the residual pressure in the fuel pipe for the next injection, and then the pressure will increase during injection.

After the pressure relief ring belt and the seat hole are worn, the fitting clearance between them increases. As a result, the lift of the valve core decreases during the fuel supply process, and the pressure relief effect reduces during the unloading process. This increases the residual pressure in the fuel pipe during the interval between fuel injections, which in turn advances the opening time of the injector pressure, increases the fuel supply of the injector, makes the fuel cut-off not direct, reduces the atomization quality, causes rough operation of the diesel engine, and leads to secondary injection and oil dripping.

Detection and Maintenance of Fuel Delivery Valve Wear

The tightness of the fuel delivery valve can be checked using the hand pump inside the oil pump. First, position the plunger of the fuel delivery pump at the lower end so that the space above the plunger is connected to the oil inlet channel, and then remove the high-pressure fuel pipe. Next, use the hand-operated starting pump. If there is no fuel transfer pump on the diesel engine, pour diesel into the oil inlet channel and wait for about 1 minute to check if there is oil overflow from the fuel delivery valve. If there is, it indicates that the fuel delivery valve is not tightly sealed.

If there is a dirt pad on the fuel delivery valve affecting its tight seal, it can be cleaned with gasoline and then reinstalled for reuse. If the conical surface of the fuel delivery valve is not tightly sealed due to wear, a small amount of chromium oxide and engine oil can be applied to the conical surface for lapping. After lapping, it must be thoroughly cleaned with gasoline, ensuring that there are no grooves or arcs on the surface and that the seal is tight. If the wear is severe, the fuel delivery valve should be replaced. If the pressure relief ring belt is excessively worn, its surface will become dull. In case there are grooves on it, replacement is necessary.

Guangxi Dingbo Generator Set Manufacturing Co.,Ltd. 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 [email protected] we will pay highly attention on your question.