Diesel fuel combustion, the normal color is generally light gray, dark gray heavy load. The diesel engine at work, occasionally there will be a row of black smoke, white smoke, smoke and other abnormal phenomenon, it is the judgment of diesel engine fault conditions, analysis as follows:
(1) black smoke
Diesel is a complex hydrocarbon that is injected into the combustion chamber, and unburned diesel is decomposed at high temperature to form carbon black. Exhaust with exhaust gas to form black smoke. Black smoke is a manifestation of incomplete combustion of fuel in a combustion chamber. The main influencing factors are as follows:
1, piston ring, cylinder liner and other wear
Baotou beiben parts of piston ring and cylinder wear, caused by insufficient pressure, make the cylinder at the end of the compression stroke, mixture proportion change, combustion of the fuel in the absence of oxygen, carbon deposit.
2 、 the injector is not working well
The fuel injector does not atomizing or dripping oil, so that the fuel can not be fully mixed with the air in the cylinder, and can not be fully combusted. The phenomenon of soot exhaust caused by poor injector operation is obvious when the diesel engine runs at low speed. Because of low speed cylinder swirl is weak, oil droplets or oil flow to reduce the possibility of beam break up and stay longer, more easy to form carbon black discharge.
3, combustion chamber shape change
The manufacturing quality of combustion chamber shape does not meet the technical requirements, the compression I sewed too too small and the position of the piston installed wrong, will cause the change of the shape of the combustion chamber, thus affecting the fuel mixed with air quality, so that the fuel combustion conditions deteriorate.
4, oil supply advance angle adjustment inappropriate
1) fuel supply advance angle is too large, too early fuel injected into the combustion chamber, the cylinder pressure due to low temperature, fuel combustion, when the piston, cylinder reaches a certain pressure and temperature, the combustible mixed gas combustion.
2) the fuel supply advance angle is too small, the fuel injected into the cylinder is too late, some of the fuel is too late to form, the combustible mixture is separated or discharged, and the fuel discharged with the exhaust gas is decomposed at high temperature to form black smoke.
5. excessive fuel supply
Excessive oil supply, so that the amount of oil into the cylinder increased, resulting in more oil, less gas, fuel combustion is incomplete. In addition, heavy work load, poor fuel quality and low operating temperature will cause soot exhaust.
(two) blue smoke
The oil enters the cylinder and evaporates into blue gas. Blue smoke is discharged with the exhaust gas, mainly due to:
1, Baotou beiben accessories clogged air cleaner, air intake or poor tank oil level is too high (oil bath air filter).
2, the fuel mixed with lubricating oil.
3, piston ring counterpart,
4. The cylinder liner near the cylinder head is burned down.