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Explanation Diesel Engine Black Smoke


Engine at work, often can appear smoked not normal phenomenon, such as black smoke, the blue smoke, white smoke, etc., which are one of the judgment condition of engine failure, specific have the following analysis:

Engine black smoke:
As a result of the incomplete combustion of diesel engine smoke root cause.There are two main types of diesel combustion caused by inadequate: insufficient into gas and oil supply is not normal.
When the engine smoke of symptoms, we easily after hard to check in the first order to the point of failure.
1.Remove the air filter, check whether the empty filter clogging.
Judgment method: disconnect the air filter, air filter and be properly, observe whether the air filter is a large number of dust scattered, and check whether there is a lot of dust inside the empty filter housings gathered themselves together, and if there is a lot of dust, you need to clean or replace air filters.After change the new air filter, if the exhaust smoke decreased significantly, the proved empty filter blockage, cause gas not free;If there was no significant alteration of the exhaust smoke, the other parts to check the air intake system.

2.The intake pipe air intake resistance is big, check for leaks air inlet pipe, or extrusion deformation cause congestion, and observe the exhaust smoke.
Reason: most of diesel engine with the present stage of engineering machinery installed exhaust turbocharger, so because of the supercharger pumping air into vacuum state, if there any funnelled inlet pipe will affect the smooth degree of the engine intake, increase the air intake resistance, reduce the engine air inflow, leading to the engine fuel and air mixing unevenly, caused the generation of black smoke.
Judgment method: start the engine and high speed on the gas in the operation, and listening to the engine intake pipe road if there is a “white” sound.If there are “white” sound, then prove the existence of the engine intake pipe road leak points, you will need to check the exact location of the leakage of dew, seal processing, or replace the new tube;If there is no “white” sound, should also check whether inlet pipe extrusion deformation, cause jam.In the treatment of the leakage and piping congestion, if no change exhaust smoke, then on to the next item.

3. Replace the diesel filter, observe the exhaust flue gas changes.
Reason: as the regional fuel quality problem, make the diesel particulate matter and water content is more, if the quality of diesel oil filter is not up to standard, or use the time more than normal making cycle and are not replaced, can cause impurity particles and water with diesel oil into the engine combustion, and damage to the fuel system, especially the efi system, makes high voltage cannot be established, insufficient jet atomization, can cause smoke phenomenon.
Judgment method: first, open the fuel tank, and open the drain switch, and the container released to receive part of the fuel, and let stand, observe whether fuel is layered or have a large number of particles, to check whether the tank contains many impurities and moisture and make the diesel pollution, cause the engine smoke.Then replace the diesel filter observation exhaust smoke after change, if the black smoke still, into the next phase of testing.

4.Injectors, high pressure pump plunger or delivery valve malfunction, swap observation flue gas change after the fuel injector.
Reason: due to product quality, working time, and the problem of maintenance is not timely cause the injector needle valve open card lag, bad atomizing injector, fuel injection pressure is not correct, cause the cylinder combustion of fuel oil is not sufficient, produce a large number of black smoke.
Judgment method: start the diesel engine’s speed, cylinder oil cut-off and observe the change of exhaust pipe outlet smoke, if a cylinder is broken after oil, diesel engine’s FSN decreases, and explain the cylinder oil supply system (plunger/delivery valve or injector) has a problem.
Determine if the cylinder oil supply system existence question, swaps with other cylinder injector, and observe the smoke.If the smoke significantly reduced or disappeared, is proved that the cylinder injector failure, need to repair or replace the fuel injector fuel injector assembly;If no obvious change in the smoke, it can be concluded that for the cylinder of high pressure pump plunger and delivery valve fault, need to replace damaged parts assembly, and the calibration and test of high pressure pump, in order to determine the high-pressure pump normal working level.
(note: for use of efi engine equipment, in the judgement in the case of smoke, also can be used interchangeably injector method to determine the specific as a result of which cylinder injector failure of smoke like now. And efi engine fuel injector is sometimes uneven injection due to line problem, also can appear the symptom of smoke happen. If after the replacement or repair injector failure remains, it is best to contact local after sales service personnel to the machine a thorough check, to determine the specific failure causes and failure points, let the equipment can work normally as soon as possible. Also has self-checking function, and electronic fuel injection engine smoke phenomenon occurs in the engine, should check whether the equipment instrument is to have the fault code, through the fault code can be more intuitive and quickly find out the fault location and fault reasons.)
We need to focus on when replacement fuel injector note: be sure to purchase by the fuel injector whether meet the requirements of engine manufacturers technical parameters and quality grades, in order to avoid because the purchase of the injector is not up to standard, causes the engine cannot reach the best working state, affect the normal use of equipment.

5.The turbocharger failure, speed is not enough, lead to engine smoke.
Reason: due to the present stage, engineering machinery mostly adopts turbo engine, so when the turbocharger fault, the fault phenomenon and air intake system jam fault phenomenon and the reasons are the same.
Judgment method: remove the intake pipe from the turbocharger, supercharger impeller, look to whether can pick, if can easily strike proved the supercharger normal;On the other hand, the turbocharger failure.Check the amount of supercharger impeller axis whether there is a big gap (shake impeller, shall have the biggest gap for the normal range of not more than 3 mm), if it is found that the impeller has a larger gap, need to replace the turbocharger.Observe the supercharger blade wheel blade fracture, wear, deformation, and observe the impeller peripheral, supercharger casing scratches, whether the supercharger chamber.If a blade fracture, bore, should be made for the turbocharger repair or replacement.



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