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You’ve probably heard about clean vs dirty diesel, but what does it actually mean? Clean diesel refers to a catch-all term that references changes in engine design, such as ultra-low sulfur fuel and common rail diesel. The result is engines which are about 99 percent cleaner than their counterparts from 10 to 20 years ago.

So, if clean diesel is good, what is dirty diesel? This term refers to diesel that has built up sludge, slime, grime, and is likely not fit for use, which means it shouldn’t be put in your vehicle. Fuel that has been sitting in storage tanks for long periods of time without proper testing or treatment starts to go bad. The following can help you tell if your fuel is dirty or clean and know how it may be affecting your vehicles.

Symptoms of having dirty diesel

How do you know the fuel is dirty? You can detect this if you begin to see varnish or sludge on your fuel system or engine. Dirty diesel often results in clogged filters and deposits in fuel injectors. Eventually, these build up into reduced vehicle performance. If you run a fleet, dirty fuel could affect every vehicle.

What causes dirty diesel?

There are a few culprits, but this section will focus on the biggest causes you should watch out for. The first problem is time. The shelf life of diesel is about 6 to 12 months, but in certain conditions (like extreme weather), it can be much shorter. Also, the longer you store diesel fuel, the more likely it will be contaminated by other issues like microorganisms.

Weather can cause water to leak into your fuel, which can result in many problems. For example, warm moisture that comes into contact with cold diesel or a cold tank could cause condensation and water leakage. Weather can also cause swings in heat and humidity which affects fuel energy content. Also, warmer temperatures naturally increase the degradation of diesel.

Finally, microorganisms are a big problem. For example, fungi and bacteria in water and can feed off the hydrocarbons in diesel. As they die, their bodies become additional contaminants in your fuel.

Other contaminants that can affect the quality of your diesel

Other contaminants that decrease fuel efficiency include lead, sulfur, and certain additives. Lead is a commonly known pollutant that is toxic to humans and can cause permanent damage to catalytic converters.

Sulfur occurs naturally in fuel, but some refining processes can remove too much. If too much sulfur is left, it can damage converters and clog filters and traps. In fact, the only way to deal with this problem is with special treatments to remove the sulfur, but these processes can damage the engine.

Finally, some additives contain metal that can cause ash to build-up in engines and result in clogging. It is important you carefully add additives to preserve the integrity of your fuel.

At Kendrick Oil, we distribute a wide variety of high-quality wholesale fuels, including red diesel, regular diesel, and premium gas. If your business is in need of bulk fuel or if you have any questions about any of our Products and Services, give us a call at (800) 299-3991. You can also Contact Us by email for more information. We have locations in Texas, New Mexico, Oklahoma, Kansas, Colorado, and Louisiana.