The “running” fault of diesel engine refers to the regular speed up and down. This fault is generally due to the fuel supply system in the air or governor caused by disorders.
Cause of failure:
1. The oil supply adjusting tooth rod in the fuel injection pump is stuck.
2. The backlash of the fuel supply rod in the fuel injection pump is too large.
3. The axial clearance of the camshaft of the injection pump is too large.
4, the tooth rod of the fuel injection pump or the pull rod pin of the fork is too loose.
5. The movable joints inside the governor are stuck or too loose.
6. The internal spring of the governor is deformed or broken.
7, the internal nozzle of the fuel injector even burned.
Any one or several of the above reasons can cause the diesel engine speed instability after starting.
Troubleshooting method:
The “running” fault of diesel engine is mostly caused by the damage of the high pressure oil pump assembly. The queuing method of this fault is to remove the high pressure oil pump and carry out correction and repair on the special platform of the high pressure oil pump. Note: do not disassemble when you do not master the working principle of the high pressure oil pump, in order to prevent improper disassembly of the governor failure, resulting in the diesel engine test engine “flying speed” phenomenon.
1. Start the diesel engine until the speed reaches 700r/min. After 1min, touch each cylinder with your hand to check its working condition. During the inspection, the exhaust temperature of the four cylinders was found to be basically the same, which indicates that the fault may be located in the high-pressure oil pump or governor.
2. After shutdown, remove the high pressure oil pump and check and debug the high pressure oil pump assembly on the test bench. In the process of inspection, it was found that the movable joints inside the governor appeared stuck, which may be the cause of the above fault.
3. After repairing the internal fault of the governor, assemble it on the diesel engine block, and then tighten the two fixing screws of the transmission connecting disc of the high pressure oil pump.
4. Adjust the fuel supply advance Angle of diesel engine to 28° or 31°.
5. Tighten the high-pressure oil pipe, prepare and check the diesel engine before starting, and then start the diesel engine to idle, observe the operation of the diesel engine, and find that the diesel generator does not appear in the process of rotation “car” phenomenon.
Post time: Feb-17-2023