What is the fault when a diesel engine emits black smoke?

[MacAyla]

Diesel engine emits black smoke due to poor atomization of diesel or incomplete combustion. The reasons why a diesel engine is difficult to start are: 1. Fault in the fuel supply system; 2. Insufficient gas pressure in the combustion chamber; 3. No fuel in the tank or forgetting to open the tank switch; 4. Blockage in the pipeline or filter; 5. Wear in the fuel injection pump; 6. Needle valve in the fuel injector stuck. Diesel engines are divided into: 1. Spark ignition engine: A gasoline engine injects gasoline into the intake pipe, mixes it with air to form a combustible mixture, which then enters the cylinder and is ignited by the spark plug to expand and perform work; 2. Compression ignition engine: A diesel engine directly injects diesel into the engine cylinder through the fuel injection pump and nozzle, where it mixes uniformly with the compressed air in the cylinder and self-ignites under high temperature and pressure, pushing the piston to perform work.