Why do car throttles turn black

A pipe that comes out of the oil chamber and is connected to the throttle valve is called: crankcase ventilation pipe. The function of this tube is to use the vacuum formed by the high-speed flow of air in the throttle to extract the oil smoke generated by the high temperature of the oil chamber into the engine for combustion, so that the exhaust gas is not only treated, but also the temperature of the oil chamber is lowered after pumping fresh air into the oil chamber.

The crankcase needs to be ventilated because it can't let the internal pressure too much; But it can't go directly to the atmosphere, which causes pollution. So it had to be sucked into the engine and burned. It's the contamination of the intake tract, which is what you say, the throttle of the car will be black.

Hope it helps.

1. Causes of black smoke.

1.The flammable mixture is too thick. 2.

There is too much oil in the engine fuel. 3.Poor piston ring or crankshaft oil seal sealing.

4.There is moisture in the fuel. 5.

Bad spark plug 6The air filter is too dirty.

2. Fault diagnosis and elimination.

1.For the inspection and diagnosis of excessive concentration of combustible mixtures, the carburetor and air filter should be checked.

2.The blend does not compare with the blend of the oil, or the wrong grade of oil is used. If the oil mixture contains too much oil or the oil quality is poor, the oil of the flammable mixture cannot be completely burned, resulting in black smoke.

In the two-stroke engine with separate lubrication method, the oil pump loses its backup adjustment and the oil supply is excessive, and the above phenomenon will also occur. At this time, the oil pump should be checked and adjusted according to the regulations to ensure that the lubricating oil is supplied proportionally at different throttle openings.

3.Excessive wear or breakage in a four-stroke engine, as well as too much oil in the crankcase, can cause oil to string into the combustion chamber and cause excessive oil in the mixture. If the crankshaft oil seal of a two-stroke engine is broken, it will also cause the oil from the transmission to string into the crankcase and enter the combustion chamber with the mixture.

4.One of the reasons for the mixing of water in the fuel is that the fuel in the fuel tank itself contains water, so the fuel tank should be cleaned and the fuel should be replaced. Another reason is that the cylinder head gasket of the water-cooled engine is stupid and broken, and cold water enters the cylinder.

If, in the absence of leakage, the water in the tank is consumed too quickly, and the exhaust smoke from the exhaust pipe is slightly white, this is mostly the reason and the head gasket should be replaced.

Black smoke from gasoline engine is rare, black smoke is mainly not completely burned fuel in the combustion chamber, in the case of high temperature and lack of oxygen, diesel can not be completely and fully combusted, so decomposition and collection to form soot, it is a small diameter of the aggregate.

Because this aggregate reacts much slower than gasified fuel, due to the high temperature and anoxic environment of the combustion chamber, it cannot be fully burned again and is discharged through the exhaust pipe, so black smoke is presented.

The direct consequence of this phenomenon is that the fuel consumption of diesel engines is very high, the power is reduced, and at the same time, a large amount of carbon deposits exist in the piston and piston ring valves. In severe cases, the piston rings will be jammed, the valve seal is not tight, and the air leakage will be accelerated, and at the same time, it will also accelerate the wear of parts, thereby reducing the service life of the engine, so this aspect should be paid special attention.