Diesel Fuel Contamination: Causes, Symptoms and Prevention

Have you noticed sludge-like buildup in the bottom of your storage tank? Do you feel your engine is taking more time to start than usual and losing power all of a sudden? The possibility is, you are using contaminated fuel. 

Unless you maintain your fuel and treat it well, you will notice diesel fuel contamination symptoms that can wreak havoc in your engine eventually! 

No matter if you are using high-quality diesel to run machinery or vehicles for aviation, agriculture, or marine, unless you seal the system appropriately and follow top-notch maintenance, the fuel can get contaminated, resulting in even system disruption!

To help you prevent diesel-quality degradation because of contamination, I gather its signs, preventive measures, and everything essential. 

Fuel Contamination

Fuel contamination is the process of degrading fuel quality by contaminants like water, algae, microorganisms, etc.

Today’s environment-friendly fuel is a mixture of 93% petroleum diesel and 7% biodiesel. This ultra-low sulfur diesel (ULSD) is excellent to decrease the earth’s carbon footprint, but it is prone to contamination, thus not favorable to the businesses that store fuel.

Causes of Diesel Fuel Contamination

The culprits that contaminate diesel are:

• Water
• Microbes
• Particulates

Water Contamination

The composition of modern biofuel makes water build-up in it unavoidable. Water can be present in the following three forms in a storage tank:

• Dissolved water
• Emulsified water
• Free water

When the dissolved water can deteriorate diesel quality, emulsified, specifically, the free water can taint it badly, causing severe damage to the engine, even following engine failure! 

Water can enter the fuel vessel in various ways:

• Biodiesel, being hygroscopic, easily penetrates water from the atmosphere.
• If the fuel container is not full, the vapor above the diesel gets mixed with it, appearing as a water-fuel emulsion.
• Open vents allow moisture to penetrate the tank.
• The temperature difference and humidity outside cause water condensation and produce water droplets inside the tank.

Microbial Contamination

• The microbes like algae and bacteria that cause diesel contamination are classified as diesel bugs and look like blackish or brown slime.
• The naturally found microorganisms in biofuel can spur in the presence of water.
• The contamination accelerates when the temperature reaches 10-40°C in the presence of water.

Particulate Contamination

Various smudge, asphalts, ferrous materials, etc., are other culprits that can contaminate the diesel and break your bank for making the system operate optimally again. 

Symptoms of Fuel Contamination

Is the back, cloudy exhaust of your car making you think the fuel is tainted? 

Don’t go with assumptions and check for the following symptoms:

• Uncontaminated diesel should appear bright and clean. If you have noticed the diesel looks muddy, the possibility is, it is tainted.
• Jammed filters are the initial indication of contaminated fuel. Filters capture smudge and other particulates from the diesel before it gets transferred to the engine. If they need frequent replacement, the most viable cause is contaminated fuel.
• Regular fuel filter clogging induces fuel pump failure as it has to operate beyond its design criteria to pass the engine the required fuel.
• If your diesel engine is operating with low-quality contaminated diesel, it may require more fuel, resulting in a higher fuel consumption rate.
• Do your fuel injectors require more cleaning and maintenance than usual? Well, injectors hardly need cleaning, but when the fuel gets tainted, the engine starts dissipating more power, and the injectors fail to operate optimally, resulting in frequent injector blockage.
• Black and heavy exhaust is another indication of degrading diesel. When your engine is hot and operates with clean fuel, it generates comparably clean exhaust than contaminated diesel.
• If your fuel smells like a ‘rotten egg’ while examination, the reason is, it contains microbes.
• Have your tank, cylinder, and piston rings decayed? Contaminated diesel does not let the fuel injectors sustain the uniform fuel flow. This non-uniformity in fuel combustion speeds up the decaying process and affects the camshaft torque.

How to Prevent Diesel Fuel Contamination

Preventing fuel contamination is inevitable, as it can make your whole system fail and cost you huge! Following some easy yet effective steps will help you keep your diesel and storage tank in top-notch condition, making your system run optimally. 

Buy from Reputable Sources

One handy way to avoid loading your fuel tank with low-grade diesel is to buy from a trustworthy and authentic seller. A reputable seller will provide his customers with high-quality fuel that contains no contaminating agents like water, microbes, or particulates. 

Change Your Fuel Filters Periodically

Another effective way to prevent contamination is to replace fuel filters periodically. I have already mentioned, these filters are responsible for filtering smudge and grime from the fuel before delivering it to the engine. Thus you can ensure your engine is getting clean diesel and working appropriately by changing them regularly. 

Test the Fuel

If you suspect your fuel is getting contaminated, go for a quick check before it gets too late. Testing enables you to go to the root cause of fuel degradation. Thus you can go for fuel polishing and bring the diesel to the optimal operating state again if possible. 

Microbial growth, being the prominent reason for deteriorating diesel quality, demands your utter conscience. 

If you want a quality kit to examine your fuel, Conidia’s diesel fuel contamination kit can be your ultimate choice. It is an on-site immunoassay antibody testing kit that enables you to detect the microbes in the earliest stages without undergoing a multi-step process. 

Ensure Tank Maintenance

To ensure your fuel is in the best condition, you must maintain your tank also. Rusty tank is another reason that degrades fuel quality adversely. Again, a well-maintained tank hinders contaminants like microbes and water from entering the fuel. 

The other measures you should adopt are:

• To keep water condensation to a minimum level, ensure keeping the fuel tank full.
• Always run the diesel through the filtration system after transporting it.
• Check the water state levels each month.
• To avoid microbes, use biocides in each 3-month.

Wrap Up

Using high-grade diesel fuel accompanied by top-notch maintenance can ensure your system can operate in its best condition, bypassing engine malfunctions. The above information I have summarised would help you identify the diesel fuel contamination symptoms and adopt the best preventive steps.