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Do you know why diesel generator sets are underpowered?

May 17, 2022
When the power of the diesel generator set is insufficient, it will cause abnormal smoke from the exhaust pipe, uneven exhaust sound, reduced speed, and unstable operation, which will affect the normal operation of the unit. So what is the reason for the insufficient power of the generator set?
Reason 1: The exhaust pipe is blocked
Blockage of the exhaust pipe will cause the exhaust to be blocked and the fuel efficiency will decrease. Power drops. It should be checked whether the exhaust guide resistance increases due to too much carbon deposition in the exhaust pipe. Generally, the exhaust back pressure should not exceed 3.3Kpa, and the carbon deposits in the exhaust pipe should be removed frequently.
Reason two, the air filter is not clean
The unclean air filter will increase the resistance, reduce the air flow, and decrease the charging efficiency, resulting in insufficient engine power. The diesel air filter element should be cleaned or the dust on the paper filter element should be cleaned as required, and the filter element should be replaced if necessary.
Reason 3: Piston and cylinder liner are strained
Due to the serious strain or wear of the piston and the cylinder liner, and the increase of friction loss caused by the glued piston ring, the mechanical loss of the engine itself increases, the compression ratio decreases, the ignition is difficult or the combustion is insufficient, the lower air charge increases, and the leakage Severe gas. At this time, the cylinder liner, piston and piston rings should be replaced.
Reason 4. The fuel supply advance angle is too large or too small
If the fuel supply advance angle is too large or too small, it will cause the fuel injection time of the fuel pump to be too early or too late (the fuel injection time is too early, the fuel combustion will be insufficient; The process is not at its best. At this time, check whether the screw of the fuel injection drive shaft adapter is loose. If it is loose, adjust the fuel supply advance angle according to the requirements and tighten the screw.
Reason 5: The cooling and lubrication system is faulty
The overheating of the diesel engine is caused by the failure of the cooling or lubricating system. In this case, the water temperature and oil temperature will be too high, and it is easy to cause the cylinder to be pulled or the piston ring to be stuck. When the exhaust temperature of the diesel engine increases, the cooler and radiator should be checked to remove scale.
Reason 6: The fuel system is faulty
(1) Air enters or is blocked in the fuel filter or pipeline, which causes the oil pipeline to be blocked, the power is insufficient, and even the fire is difficult. The air entering the pipeline should be removed, the diesel filter element should be cleaned and replaced if necessary.
(2) Oil leakage, seizure or poor atomization caused by the damage of the fuel injection couple, at this time, it is easy to lead to lack of cylinders and insufficient engine power. It should be cleaned, ground or replaced in time.
(3) Insufficient fuel supply of the fuel injection pump will also cause insufficient power. The coupler should be checked, repaired or replaced in time, and the fuel supply of the fuel injection pump should be readjusted.
Reason 7: The surface of the connecting rod bearing bush and the crankshaft connecting rod journal is biting
The occurrence of this situation will be accompanied by abnormal sound and oil pressure drop, which is caused by blocked oil passage, damaged oil pump, blocked oil filter element, or low oil hydraulic pressure or even no oil. At this time, the side cover of the diesel engine can be removed, and the side and clearance of the big end of the connecting rod can be checked to see if the big end of the connecting rod can move back and forth.
At this time, for the supercharged diesel engine, in addition to the above reasons, the power of the diesel engine will be reduced, if the bearing of the supercharger is worn, the intake pipe of the press and the turbine is blocked by dirt or leaks, the power of the diesel engine can also be reduced. When the above situation occurs in the supercharger, the bearings should be overhauled or replaced, the intake pipe and the casing should be cleaned, the impeller should be cleaned, and the joint nuts and clamps should be tightened.
Reason 8: The cylinder head group is faulty
(1) Insufficient intake air volume due to exhaust gas leakage or mixed exhaust gas in the intake air, resulting in insufficient fuel combustion and reduced power. The mating surface of the valve and the valve seat should be ground to improve its tightness, and if necessary, replace it with a new one.
(2) Air leakage at the joint surface of the cylinder head and the body will cause the air in the cylinder to enter the water channel or oil channel, causing the coolant to enter the engine body. Lack of motivation. Due to the damage of the cylinder head gasket, an air flow will rush out from the cylinder head gasket during shifting, and there will be blisters on the gasket when the engine is running. At this time, the cylinder head nut should be tightened according to the specified torque or the cylinder head gasket should be replaced.
(3) Incorrect valve clearance will cause air leakage, resulting in decreased engine power and even difficulty in catching fire. The valve clearance should be readjusted.
(4) Damage to the valve spring will make it difficult to return the valve, the valve will leak air, and the gas compression ratio will decrease, resulting in insufficient engine power. Damaged valve springs should be replaced in time.
(5) Air leakage from the injector mounting hole or damage to the copper pad will result in a lack of cylinders, resulting in insufficient engine power. It should be removed for inspection and replaced with damaged parts. If the inlet water temperature is too low, the heat dissipation loss will increase. At this time, the inlet temperature should be adjusted to meet the specified value.