When the engine emits white smoke, some operators do not know how to judge which parts have faults. This page will introduce the causes of white smoke, fault causes and how to diagnose and eliminate them.
1. Causes of white smoke
Since the diesel entering the combustion chamber is not burned after evaporation, it is milky white and discharged from the exhaust pipe; Or there is water in diesel oil. The water evaporates in the cylinder to form steam. When the steam is discharged, it is white.
2. Fault cause
(1) There is water in the diesel oil or water leakage in the cylinder due to the flushing of the cylinder gasket and the rupture of the cylinder head or cylinder block.
(2) Cylinder pressure too low.
(3) The operating temperature is too low.
(4) Poor spray quality of fuel injector.
(5) Diesel is of poor quality.
(6) The fuel supply time of the fuel injection pump is too late.
3. Diagnosis and troubleshooting of white smoke
(1) When the diesel engine is running, loosen the bleed screw or high-pressure oil pipe connector on the unit pump and check whether there are water droplets in the oil flow. If water drops appear, it indicates that the reason for white smoke from the exhaust pipe is the water in the diesel oil. Drain the water in the oil tank, diesel filter and high and low pressure oil circuits.
(2) If there is no water in the diesel oil, open the water tank cover and observe whether there are bubbles in the water tank. If there are bubbles, it means that the cooling water enters the cylinder. The cylinder head shall be removed to find out the fault position for maintenance or replacement.
(3) If no water enters the cylinder, check the cylinder pressure. If the cylinder pressure is too low, repair it.
(4) Driving in winter, if the diesel engine often works at low temperature, it will also make the exhaust pipe emit white smoke. Check whether the shutter is closed tightly and whether the thermal sleeve is in good condition. Otherwise, it shall be repaired.
(5) If there are no problems above, check the spray quality of the fuel injector.
(6) If the spray quality meets the requirements, check the oil supply timing and adjust it as required. The poor quality of diesel also has a certain impact on the white smoke from the exhaust pipe of diesel engine. If necessary, replace new oil for comparative test.
