Could Your Diesel Fuel Tank Be Contaminated?


   It is estimated that eight out of every ten diesel engine failures have been directly related to contaminated fuel. The build-up of contaminates in fuel storage tanks can quickly

  clog filters and fuel injectors resulting in engine shut down, fuel pump wear and diesel engine damage.


  What are the problems that occur with stored diesel fuel?

  Water condensation & separation , Algae formation , Catalytic fines, dirt & rustic silicates , Fungi growth , Clouding, Gel formation, Gums & resins due to oxidation.

Engine manufacturers design diesel engines to operate on fuels meeting the properties of ASTM designation D975 (grades 1-D and 2-D).


Your diesel powered equipment  represents a large investment where reliability is critical.  You can have state-of-the-art equipment, but without “clean” fuel it won’t perform. Stored diesel  fuel quickly begins to degrade because of living microbial (bacteria) and fungi which thrive on impurities in the fuel, air, moisture, and dust.  Factors such as climate, weather, tank conditions or tank design influence how quickly these “bugs” develop into solids and sludge that can clog fuel lines and damage engines.


 As the particulates develop, the slime they create sticks to the walls of the tanks and begin a corrosion process that can also lead to tank damage and possible fuel leakage.


Additives are biocides and are similar to “antibiotics” that kill fuel bacteria. But like human antibiotics, the right one must be used for each microbial, in the right amounts, and at the right intervals. Improper application is like stopping a human antibiotic treatment after 3-4 days. The germs are still there, and will increase immediately. In addition, some biocides are water-soluble and actually breakdown with contact, which can also be a problem. If successful, the effect of the additives alone is only temporary and will not eliminate the sludge problem.

Contaminated fuels must sometimes be removed for tank repairs and fuel replacement.


 Is the quality of diesel fuel today lower than in the past, in some cases, yes?  In the past, diesel fuel remained in refinery storage tanks long enough to naturally separate and settles,  allowing it to be drawn off.  Due to the increased demand for diesel fuel today, it may not remain stationary long enough to allow for proper settling.  As a result, suspended water can be passed on with the fuel to the user.


 In addition, to reduce production costs, diesel fuel is sometimes refined from more marginal portions of the crude oil barrel. This results in a lower-grade product that is inherently thicker and more susceptible to acute water contamination.


Understanding the threat that water poses to a diesel engine means realizing the added burden placed upon diesel fuel as opposed to gasoline. Gasoline acts as a fuel only. Diesel fuel, on the other hand, also must cool and lubricate injection system parts. These parts are engineered to incredible tolerances – up to 0.0002 of an inch – and any contamination mean rapid wear or seizure. Water not only displaces the diesel fuel; it acts as a cutting agent, scoring these parts.


Water that enters the combustion chamber results in even more serious damage. When it comes in contact with the heat of the combustion chamber (In excess of 2,000 degrees F), it immediately turns to steam and often literally explodes the tip of the injector. Water causes corrosion of tanks, lines, injectors, and greatly reduces combustibility.


Bacteria also present a serious problem. Bacteria feed on nitrogen, sulfur and iron oxides. Therefore, compounds of these elements should be excluded from fuel storage tanks.


Diesel fuel begins to deteriorate as soon as it is produced. This deterioration does not present a major problem if the fuel is consumed relatively quickly. However, fuel deterioration not only affects pump ability and combustibility, but it will most likely cause engine damage.