How to Properly Maintain the Fuel Injection Pump of a Diesel Generator Set

The fuel injection pump is an important part of the fuel supply system of a diesel generator set. Its working condition directly affects the power, economy and reliability of the diesel generator set. Correct maintenance is an important prerequisite for ensuring the normal operation of the fuel injection pump and prolonging its service life. In this article, Dingbo Power will introduce to you the correct maintenance method of diesel generator set fuel injection pump.

1. Use and filter the diesel oil well to ensure that the diesel oil entering the fuel injection pump is highly clean.

Generally speaking, the filtration requirements of diesel engines for diesel are much higher than those for gasoline engines. When in use, the diesel oil that meets the requirements should be selected, and it should be deposited at least 48 hours. Strengthen the cleaning and maintenance of the diesel filter, clean or replace the filter element in time; clean the diesel tank in time according to the operating environmental conditions, thoroughly remove the sludge and moisture at the bottom of the fuel tank, and any impurities in the diesel will affect the plunger and oil of the fuel injection pump The valve assembly and transmission parts cause severe corrosion or wear.

2. Frequently check whether the quantity and quality of the oil in the oil sump of the fuel injection pump meet the requirements.

Before starting the diesel engine, check the quantity and quality of the oil in the fuel injection pump (except for the fuel injection pump that relies on forced engine lubrication) to ensure that the quantity of oil is sufficient and the quality is good. The early wear of the plunger and the delivery valve assembly results in insufficient power of the diesel engine, difficulty in starting, and in severe cases, corrosion of the plunger and delivery valve assembly. Due to internal leakage of the oil pump, poor operation of the oil outlet valve, wear of the oil delivery pump tappet and casing, and damage to the sealing ring, diesel will leak into the oil pool and dilute the oil. Therefore, the oil should be replaced in time according to the quality of the oil. Thoroughly clean the pool to remove the sludge and other impurities at the bottom of the oil pool, otherwise the engine oil will deteriorate if it is not used for a long time. The amount of oil should not be too much or too little. Too much oil in the governor will easily cause the diesel engine to runaway. 

3. Regularly check and adjust the fuel supply advance angle of the fuel injection pump and the fuel supply interval angle of each cylinder.

When in use, due to the loosening of the coupling bolts and the wear of the camshaft and roller body parts, the fuel supply advance angle and the fuel supply interval angle of each cylinder often change, which makes the diesel combustion worse and the power of the diesel generator set, The economic efficiency becomes worse, at the same time it is difficult to start and cause problem of unstable operation, abnormal noise and overheating, etc. In actual use, many users pay attention to the inspection and adjustment of the overall fuel supply advance angle, but ignore the inspection and adjustment of the fuel supply interval angle (involving the adjustment of the fuel supply advance angle of a single pump). However, due to the wear of camshafts and roller transmission components, the fuel supply of the remaining cylinders is not always in time. It will also cause difficulty in starting diesel generator sets, insufficient power, and unstable operation, especially for fuel injection pumps that have been used for a long time. In other words, more attention should be paid to the inspection and adjustment of the oil supply interval angle.

4. Regularly check and adjust the fuel supply of each cylinder of the fuel injection pump.

Due to the wear of the plunger assembly and the delivery valve assembly, the internal leakage of diesel will be caused, and the fuel supply of each cylinder will be reduced or uneven, resulting in difficulty in starting the diesel generator set, insufficient power, increased fuel consumption, and unstable operation. Therefore, it is necessary to regularly check and adjust the fuel supply of each cylinder of the fuel injection pump to ensure the power of the diesel generator set. In actual use, the fuel supply of each cylinder can be determined by observing the exhaust smoke of the diesel engine, listening to the sound of the engine, and touching the temperature of the exhaust manifold.

5. Check the camshaft clearance regularly.

The requirements for the axial clearance of the camshaft of the fuel injection pump are very strict, generally between 0.03 and 0.15mm. If the clearance is too large, it will aggravate the impact of the roller transmission components on the cam working surface, thereby increasing the early wear of the cam surface and changing the supply. Oil advance angle; camshaft bearing shaft and radial clearance is too large, it is easy to cause the camshaft to run unsteadily, the oil quantity adjustment rod shakes, and the oil supply changes periodically, which makes the diesel generator set run unsteadily. Therefore, it is necessary to check and adjust regularly. When the axial clearance of the camshaft is too large, gaskets can be added on both sides for adjustment. If the radial clearance is too large, it is generally necessary to replace it with a new one.

6. It is necessary to regularly check the sealing condition of the valve assembly on the machine.

The fuel injection pump has been working for a period of time. By checking the sealing condition of the delivery valve, a rough judgment can be made on the wear of the plunger and the working condition of the fuel pump, which is beneficial to determine the repair and maintenance methods. When inspecting, unscrew the high pressure oil pipe joints of each cylinder and pump oil with the hand of the oil pump. If oil is found to flow out from the oil pipe joints on the top of the fuel injection pump, it means that the oil outlet valve is not well sealed (of course, if the oil outlet valve spring is broken, it will also If this happens), if the multi-cylinder has poor sealing, the fuel injection pump should be thoroughly debugged and maintained, and the matching parts should be replaced.

7. Use standard high-pressure tubing.

During the fuel supply process of the fuel injection pump, due to the compressibility of diesel and the elasticity of the high-pressure oil pipe, the high-pressure diesel will form pressure fluctuations in the pipe, and it takes a certain time for the pressure wave to pass through the pipe. In order to ensure that the oil supply interval angle of each cylinder is consistent, the oil supply The quantity is uniform, the diesel generator set works smoothly, and the length and diameter of the high-pressure oil pipe are selected after calculation. Therefore, when the high-pressure oil pipe of a certain cylinder is damaged, the oil pipe of standard length and pipe diameter should be replaced. In actual use, due to the lack of standard oil pipes, other oil pipes are used instead, regardless of whether the length and diameter of the oil pipes are the same, so that the length and diameter of the oil pipes are very different. Although it can be used in emergency, it will cause the oil supply of the cylinder. The advance angle and fuel supply have changed, causing the diesel generator set to work unevenly. Therefore, standard high-pressure fuel pipes must be used in use.

8. Regularly check the wear of related keyways and fixing bolts of diesel generator sets.

Related keyways and bolts mainly refer to camshaft keyways, coupling flange keyways (oil pumps that use couplings to transmit power), half-round keys, and coupling fixing bolts. The camshaft keyway, flange keyway, and half-round key of the fuel injection pump are worn for a long time due to long-term use, which makes the keyway wider, the half-round key is not installed firmly, and the fuel supply advance angle changes; the heavy key rolls off, resulting in power transmission failure Therefore, it is necessary to check regularly and repair or replace worn out parts in time.

9. The worn plunger and delivery valve should be replaced in time.

When it is found that the diesel generator set is difficult to start, the power drops, and the fuel consumption increases, if the fuel injection pump and the fuel injector are still not improved, the plunger of the fuel injection pump and the fuel delivery valve should be disassembled and inspected, such as the plunger and the fuel delivery valve wear. To a certain extent, it should be replaced in time, and do not insist on reuse. The loss of the diesel generator set due to the wear and tear of the diesel generator set, such as the difficulty in starting, the increase in fuel consumption, and the lack of power, far exceed the cost of replacing the coupling. After the replacement, the power and economy of the diesel generator set will be significantly improved. Replace worn parts in time.

10. The accessories of the fuel injection pump must be properly maintained.

The side cover of the pump body, the oil dipstick, the fuel plug (respirator), the oil spill valve, the oil sump plug, the oil flat screw, the fixing bolt of the fuel pump, etc., must be intact. These accessories are essential to the work of the fuel injection pump. Important role. For example, the side cover can prevent the intrusion of impurities such as dust and moisture, the respirator (with filter) can effectively prevent the oil from deteriorating, and the spill valve ensures that the fuel system has a certain pressure without entering air. Therefore, these accessories must be maintained and repaired or replaced in time if they are damaged or lost. Many important parts of diesel generator sets need regular maintenance or replacement if broken, so as to ensure the normal operation of diesel generator sets.

We hope that the above helps you understand the maintenance methods of fuel injection pump. Guangxi Dingbo Power Equipment Manufacturing Co., Ltd is a diesel generator set manufacturer integrating the design, supply, commissioning and maintenance of diesel generator sets. You are welcome to contact us by email dingbo@dieselgeneratortech.com.