If the installation of the exhaust system is unreasonable, for example, the exhaust pipe is too thin, too long or the muffler is not suitable, etc., it may increase the exhaust resistance, make the exhaust of the diesel engine not smooth, and cause the diesel engine to emit black smoke.
If you need to replace the exhaust system components (exhaust connection pipe and muffler), you must choose the same product that is compatible and matched with the original exhaust system. The diameter of the exhaust connection pipe must not be smaller than the original pipe diameter. The exhaust of the muffler The throughput cannot be lower than the allowable throughput of the original muffler, and the back pressure (muffler exhaust resistance) cannot be higher than the original allowable value.
Under normal circumstances, if the exhaust system is not modified, the problem of excessive exhaust back pressure will not generally occur. If there is a problem with the exhaust system, in addition to black smoke, the diesel engine also has the following phenomena:
Diesel engine power is insufficient. Diesel engine exhaust temperature is high. Fuel consumption may increase. The basic method to confirm whether there is a problem with the exhaust system is: remove the exhaust pipe, start the diesel engine to run at low speed, observe the smoke of the exhaust port of each cylinder Normal, it means that there is no problem with the diesel engine itself. Then install the exhaust pipe and start the diesel engine to run at the same speed at low speed. Observe the smoke color of the exhaust pipe outlet. If the smoke is large, it means that the exhaust system has a problem.
Elimination method: After confirming that there is a problem with the exhaust system, the entire system needs to be modified:
Replace the muffler, choose a muffler with a larger exhaust gas throughput and a smaller exhaust back pressure:
Replace the connecting pipe between the outlet of the exhaust pipe of the diesel engine and the muffler, choose a large diameter straight exhaust pipe and a large arc transition to reduce the right angle transition.
