why does diesel generator emit white smoke

In the last blog, we learned that diesel generators produce smoke in three colors: black, white, and blue. Today, we will follow BISON to learn more about white smoke emissions. White smoke is different from colorless, which is the white color of water vapor. White smoke from diesel generators is caused by unburned fuel in the exhaust gas or water in the fuel. The white smoke being emitted is vapor from water in the diesel or fuel that is not burning properly in the engine cylinders.

In this article, BISON will take a closer look at the causes of white smoke in diesel generators. Provide preventive measures and solutions. With this knowledge, you will not only become proficient at understanding "generator signals" but you will also be able to prevent these problems from occurring.

What are the common causes of white smoke from diesel generator?

There are many reasons for diesel engines to emit sun smoke, mainly including the following aspects:

• Low body temperature: When the diesel generator temperature is low, the diesel may not be able to vaporize and burn effectively. This can result in a milky mist of oil coming out of the tailpipe, as some of the diesel fuel turns to vapor without being fully burned. This phenomenon is particularly common during cold starts, such as in winter. However, as the engine temperature increases, the smoke color will usually return to normal.

• Water in combustion chamber: Minor quantities of water or leaks infiltrating fuel system could potentially blend with diesel fuel. This water-diesel mix can then travel to combustion chamber, where it undergoes a heating process during combustion, transforming into steam. This steam is subsequently released from the exhaust pipe, manifesting as white smoke.

• Delayed diesel injection: When fuel injection timing is delayed, can lead to incomplete combustion. If diesel is introduced into cylinder at a later phase, lower temperature might induce some of the diesel to evaporate without fully combusting. This unburned fuel vapor is consequently released as white smoke.

• Fuel injector or pump damage: It can cause poor fuel atomization and subsequently, incomplete combustion. As a result, unburned fuel begins to amass in the exhaust pipe, accompanied by hot exhaust gases. This combination eventually manifests as white smoke emissions.

• Low cylinder pressure: Due to pistons and cylinders wear and tear on engine components, undercompression can occur. In turn, the combustion process is less efficient, so some diesel fuel may evaporate without being fully burned. This unburned fuel is then released as white smoke.

• Intake valve failure: Intake valve does not seal tightly, it could lead to production of white smoke. 

• Mechanical problems: Certain mechanical issues, such as loose cylinder head bolts, damaged cylinder gaskets, or fractures in cylinder liners, could allow cooling water to invade the cylinder, due to the resultant pressure differences. This inadvertent ingress of water can subsequently culminate in the emission of white smoke.

• Fuel injection pump problems: Such as an inability to regulate the amount of fuel or an incorrect compression ratio, may cause a diesel generator to emit white smoke.

• Poor quality diesel or water contamination: Cause water contamination in the fuel entering engine cylinders. This results in uneven mixing of air and fuel, leading to the production of water vapor during compression and combustion, ultimately resulting in white smoke emissions.

Understanding these factors can help diagnose and resolve issues related to diesel generator white smoke emissions, ensuring optimal performance and efficiency.

How to troubleshoot white smoke from diesel generator

• Check the fuel supply. If the fuel is turbid and has a peculiar smell, it indicates that the oil quality is abnormal and does not meet the applicable oil brand number.

• Check the fuel tank for rust or holes that could prevent water from getting into the fuel. If water enters the fuel, the fuel in the fuel injection pump and diesel filter tank should be drained, fully stored in a container, and the water should be removed before use.

• Drain all diesel fuel from the fuel lines, clean and replace the fuel.

• Check to see if air filter is clogged or dirty, which can affect air-fuel mixture, causing incomplete combustion and white smoke emissions. If necessary, check and replace air filter to ensure proper airflow.

By investigating the above potential causes, you can effectively eliminate and solve the problem of white smoke emission from diesel generators and reduce the probability of white smoke emission from diesel generators.

If the problem is solved, start the diesel generator again. The diesel generator may first start emitting white smoke, then turn to black smoke, and finally after a few minutes, the exhaust smoke should become clear. Then diesel generator should run smoothly without problems.