What kind of smoke is normal for diesel engines?

The diesel engine is in good technical condition. When it works normally, the diesel injected into the combustion chamber can be fully mixed with air and completely burned, and the discharged exhaust gas should be colorless or light blue or light gray. If the exhaust gas emitted by diesel engine is white, black and blue under common working conditions, it means that the exhaust of diesel engine is abnormal, and the reasons should be found and the faults should be eliminated.

The essential reason of black smoke in exhaust gas is that too much fuel is injected into the combustion chamber by diesel engine, which is mixed with air in a high proportion or poorly, resulting in incomplete combustion of diesel oil, and unburned diesel oil is decomposed at high temperature to form black smoke, which is discharged together with exhaust gas when it is exhausted.

Extended information:

Notes:

1. Maintain the normal water temperature (75 C ~ 95 C). When discharging cooling water, you must first open the radiator cover (it must be opened after the water temperature drops to avoid scalding), and then unscrew the water drain switch on the cylinder block.

2. The normal oil pressure at medium speed should be .25~.55MPa.

3. The load capacity must be strictly controlled, and overloading is not allowed, otherwise the reliability and service life of the diesel engine will be affected.

4. Run-in at medium speed and low load should be carried out after installing or replacing the injector, and the running-in time should be no less than 3 minutes.

5, in the process of operation, if found abnormal phenomenon, to stop in time.

6. Newly installed diesel engine or diesel engine after overhaul must be run-in before operation.

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