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Diesel engine power shortage causes and solutions
- May 09, 2018 -

1, the air filter is not clean


Unclean air cleaners will cause increased resistance, reduced air flow, and reduced aeration efficiency, resulting in insufficient engine power. The diesel air cleaner cartridge should be cleaned or dust should be removed from the paper filter element, and the filter cartridge should be replaced if necessary.


2, exhaust pipe obstruction


Blocking the exhaust pipe will cause the exhaust to be blocked and fuel efficiency to decrease. Power drops. It should be checked whether there is an increase in the exhaust gas exhaust resistance due to too much carbon deposit in the exhaust pipe. General exhaust back pressure should not exceed 3.3Kpa, usually should always clear the carbon deposit in the exhaust pipe.


3, fuel supply angle is too large or too small


If the fuel injection angle is too large or too small, the injection time of the oil pump will be too early or too late (if the fuel injection time is too early, the fuel will burn insufficiently, if it is too late, white smoke will be emitted, and the fuel oil will also be insufficiently burned). The process is not at its best. At this time, check whether the fuel injection drive shaft adapter screw is loose. If it is loose, adjust the fuel supply advance angle as required and tighten the screw.


4, piston and cylinder sleeves


As the piston and cylinder liner are severely damaged or worn, and the friction loss caused by piston ring cementation increases, the mechanical loss of the engine itself increases, the compression ratio decreases, the ignition is difficult or the combustion is insufficient, and the under inflation increases. Severe gas. At this point, the cylinder liner, piston and piston ring should be replaced.


5, the fuel system is faulty


(1) The fuel filter or pipeline enters the air or becomes obstructed, causing the oil path to be blocked, insufficient power, and even the difficulty of catching fire. The air entering the pipeline should be removed, the diesel filter cleaned, and replaced if necessary.


(2) Damage to the fuel injection coupling causes oil leakage, seizure, or poor atomization. This can easily lead to a missing cylinder and insufficient engine power. Should be cleaned, ground or replaced in a timely manner.


(3) Insufficient fuel supply to the fuel injection pump will also result in insufficient power. Check, repair or replace the coupling parts in time and readjust fuel supply to the fuel injection pump.


6, the cooling and lubrication system is faulty


The overheating of the diesel engine is caused by a failure of the cooling or lubrication system. In this case, the water temperature and the oil temperature are too high, and the pull cylinder or the piston ring is easily jammed. When the exhaust temperature of the diesel engine increases, the cooler and radiator should be checked to remove scale.


7, the cylinder head group is faulty


(1) The lack of intake air due to exhaust gas leakage or mixed exhaust gas in intake air leads to insufficient fuel combustion and power drop. The mating surfaces of the valve and the valve seat should be repaired to increase their tightness and be replaced if necessary.


(2) Leakage at the joint between the cylinder head and the body will cause the air in the cylinder to enter the water channel or the oil passage, causing the coolant to enter the engine body. If it is found that it is not timely, it will lead to “slippery shoes” or black smoke, thus making the engine Lack of motivation. Due to the damage of the cylinder head gasket, there will be a flow of air from the cylinder head during gear change. When the engine is running, there will be blisters at the gasket. Tighten the cylinder head nut or replace the cylinder head gasket according to the specified torque.


(3) Incorrect valve clearance can cause air leakage, resulting in a decrease in engine power and even difficulty in ignition. The valve clearance should be re-adjusted.


(4) Damage to the valve spring will result in difficulty in returning the valve, leakage of the valve, and reduction in the compression ratio of the gas, resulting in insufficient engine power. Damaged valve springs should be replaced promptly.


(5) Air leakage or copper mat damage to the injector mounting hole can cause cylinder deficiencies, resulting in insufficient engine power. Remove the inspection and replace the damaged part. If the inlet water temperature is too low, heat loss will increase, and the inlet temperature should be adjusted to meet the specified value.


8, the connecting rod bearing and the crankshaft connecting rod journal surface bite


The occurrence of such a situation will be accompanied by abnormal sounds and a drop in oil pressure. This is due to oil engine oil blocked, oil pump damaged, oil filter blocked, or the oil is too low or even no oil. At this time, the side cover of the diesel engine can be disassembled, and the clearance between the side of the big end of the connecting rod can be checked to see whether the big head of the connecting rod can move back and forth. If it cannot move, it indicates that the hair has been bitten and the connecting rod bearing should be repaired or replaced.


At this time, for a supercharged diesel engine, besides the above reasons, the power will drop, and if the bearing of the supercharger wears, the intake line of the press and the turbine is blocked by dirt or leaks, the power of the diesel engine can also be reduced. When the turbocharger appears above, it is necessary to repair or replace the bearing, clean the inlet pipe and casing, clean the impeller, and tighten the joint nut and clamp.