What causes black soot in a diesel engine?

Incomplete combustion occurs and soot is formed when there is an overabundance of fuel (both diesel fuel and lube oil), insufficient residence time in the combustion zone, and/or non-availability of sufficient oxidants. Over-fueling is the primary cause of black smoke from the exhaust of a heavy duty diesel engine.

What does Black smoke mean on a diesel?

Restricted Air Black smoke is partially-burned fuel. An engine that’s running properly will burn all of the diesel fuel completely, making CO2 and water. So black smoke means something is causing the fuel to not burn completely.

What causes high soot levels in a diesel engine?

Engines that have improper fuel combustion or have malfunctioning fuel injectors can cause additional buildup of soot, he adds. Also, operating conditions, such as excessive engine idling or lugging the engine, can increase the level of soot.

Is soot bad for diesel?

Black smoke is high in carbon or soot, which is an undesirable product of diesel combustion. Now, the combustion of diesel is a complicated process of breaking down the various hydrocarbon fuel molecules into progressively smaller and smaller molecules, by burning in the presence of oxygen.

Is black smoke from a diesel normal?

Black Smoke – this is the most common one and is really just an imbalance in the air to fuel ratio – too much fuel to not enough air. This means either too much fuel is being added to the mix or there’s not enough oxygen being supplied to burn the fuel.

Is black diesel smoke bad?

The simple answer is, the fact that you are not seeing any black smoke is a good thing. A properly running diesel engine should not have any smoke at all. Black smoke is an indication of restricted air among other things. Newer common-rail trucks can make more than 1,000 horse power while being nearly smoke-free.

What causes black smoke in a diesel engine when accelerating?

Black smoke indicates that the fuel is not burned properly. The internal combustion process in diesel cars requires a certain mixture of fuel and air. The ratio of fuel and air should be proper, otherwise, the mixture will be too rich, which will result in black smoke.