Common faults of diesel generator sets

On the basis of understanding the structural principle of diesel engines, it is also necessary to further understand under what conditions the diesel engine can operate normally. Once a fault occurs, how to analyze the cause of the fault according to the fault phenomenon, through in-depth and detailed analysis, can we find the correct treatment method and eliminate the fault.

1. The diesel engine cannot start

At room temperature, the diesel engine should generally start smoothly within a few seconds. Sometimes it is normal to start it 1 to 2 times repeatedly. If the diesel engine still cannot ignite after 3 to 4 repeated starts, it should be regarded as a starting fault. It is necessary to find out the cause and wait for the fault to be eliminated before starting it again. See the table below for details:

Fault phenomenon

The diesel engine cannot start

Fault cause

①The starting battery is insufficient. ②The wiring of the starting system circuit is wrong or the electrical parts are in poor contact. ③The carbon brush of the starting motor is in poor contact with the commutator.

Troubleshooting method

①Replace a battery with sufficient power or add a battery in parallel. ②Check whether the wiring of the starting circuit is correct and reliable. ③Repair or replace the carbon brush, clean the surface of the commutator with wood sandpaper, and blow away the dust.

2. High cooling water temperature

First, the surface of the cooling water tank radiator is not clean. A dusty environment is easy to block the radiator surface. It is also possible that when the unit is running, debris is sucked into the water tank by the cooling fan to block ventilation and cause poor heat dissipation. At this time, it can be solved by washing the surface of the water tank radiator with water or removing debris. Second, there is insufficient coolant in the cooling water tank. It is necessary to check the cause of the loss of cooling water. You can check whether there is any leakage in the cooling water pipes of the cooling water tank and the fuselage. If there is a leak, repair it immediately. Then add coolant to the normal level. Third, the thermostat fails and cannot open, so that the circulation path of the cooling water cannot be changed when the water temperature of the cooling water changes, and the flow of cooling water entering the cooling water tank cannot be controlled, and the purpose of regulating the cooling water temperature cannot be achieved. At this time, the thermostat needs to be replaced.

3. The generator set exhaust emits black smoke

The quality of the fuel used is poor and contains many impurities. Impurities block the injector, which makes it impossible to completely burn in the cylinder and cause black smoke; in addition, the engine injector has high pressure when injecting, and some fine and hard impurities will scratch the inner wall of the injector. When the nozzle is scratched, the accuracy of the fuel injection is changed, the fuel injector is damaged, and the engine is greatly damaged. If the fuel injector is damaged, black smoke will still be emitted even if qualified fuel is used. Therefore, the quality of the fuel must be strictly controlled, and the use of qualified fuel is beneficial to the service life of the engine. There are a lot of dust and debris in the environment, and the air filter is seriously blocked. The blockage of the air intake filter causes insufficient combustion air in the cylinder and incomplete combustion. Clean or replace the air filter and keep the environment clean. In addition, the timing of the engine injection is incorrect. The work of each cylinder of the engine depends on the calibration of its injection time, that is, the piston needs to correspond to the injection during the work process, and the time difference between the two will cause incomplete combustion and black smoke. Because the timing calibration requires strong professional technology, it is recommended to contact the manufacturer to adjust the engine injection timing and valve clearance.

4. Blue smoke from the diesel generator exhaust

It is generally caused by too much oil in the filter (that is, too much oil is added during maintenance), which can be solved by reducing the oil to the specified level. In addition, it may also be caused by the piston ring being stuck or worn too much, and the lack of elasticity causing the oil to leak into the combustion chamber and burn. In this case, you need to contact the manufacturer to clean the piston ring or replace the leaking piston ring.