Diesel Fuel Polishing

There is More to Fuel Polishing Then Adding Chemicals and Filter Your Fuel

Black - slimy fuel filter

Most diesel engine failures originate in the fuel tank. Maintaining diesel fuel quality has been the subject of many articles.  But what do you do when your diesel fuel that has “gone bad”. Many companies offer what they call diesel fuel polishing with varying claims, but with little substance to these claims.

The importance of Diesel Fuel Management cannot be understated. Diesel fuel problems, the causes and cures, are discussed elsewhere in this web site (click here to read and understand The Real Story of Bad Diesel Fuel). The problem addressed here is terminology! What is diesel fuel polishing, and what is not diesel fuel polishing?

Fuel Polishing is the popular term commonly used for treating bad diesel fuel. But not all Fuel Polishing is the same. Many vendors hype a filtration processes claiming that they “polish your fuel” and will return it to usable quality.  Filtering is not Fuel Polishing.

Most all of these processes, however, depend heavily on the addition of chemicals.  They echo the story of the chemical companies that treating or preventing microbial contamination is best handled with chemical biocides. Chemicals do not turn bad fuel into good fuel.

And repeated use of biocides in the same fuel often exacerbates the problem by further degrading the fuel at the molecular level.

Filtration Does Not Make Bad Fuel Good

Their story also makes extensive use of filtration machines.  Sometimes these machines use two or three filters in a row with decreasing micron rated filter elements.  Others use some novel filtering media, such as paper towels or some other “proprietary” means of removing solids from the fuel. But these approaches only treat the symptoms of the problem.

Fuel that has been degraded with contamination from microbial infestation is a common problem and a well-known subject of discussion. This problem, however, is only part of what needs to be addressed, and really is a minor part of the overall problem. Chemicals do a pretty good job, but are seldom fully effective as they cannot penetrate the bio-film that builds up on the tank sides and bottom.  The chemicals are not “tank cleaning” chemicals.  They become diluted and the microbial growth comes back in time.  They want you to buy more chemicals.

The Re-Fueling Conundrum

The biocide chemicals that do reach the organic growth strongly react with the microbes, but do not just make them disappear.  They shock the microbes and cause the organic matter to form solids that settle in the bottom of your fuel tank. These solids get stirred up each time you re-fuel the tank.  They end up getting pulled to your fuel filter, usually continuing over a long period of time, and necessitate frequent fuel filter changes.

Having your fuel treated with any of these pure filtration systems on the market do not eliminate the need for periodic chemical treatments.

The Darkening of Fuel Problem

The problem that chemicals and filtration does not address is the problems associated with the agglomeration of the fuel asphaltenes.  These are a high carbon content, heavy end crude oil molecule that is part of the heavy end of the crud oil from the refining process.  Most of this component ends up in the heaviest component of crud oil: asphalt. You don’t see them as they are very small coming from the refinery and are in solution in the fuel.

This agglomeration leads to these small components forming larger and larger clusters of solids.  As they grow they become very difficult to completely burn in the combustion chamber.  These clusters also accumulate around the injector components and create blockages in the orifice where fuel is spayed into the combustion chamber, compromising the injector spray pattern.

The presence of this degraded fuel may first be evident from the presence of black smoke from exhaust and less than acceptable engine performance. These solids may grow so large that they will not pass through the filter element and become part of the polymer and sludge build up plugging the filter (more information on this at The Real Story of Bad Diesel Fuel article). Short fuel filter life is the next sign of fuel degradation problems (see picture above). Neither chemicals nor filtration will reverse this aspect of fuel degradation.

The Process of Fuel Conditioning

The LG-X Series Fuel Conditioner, performs on two levels:

First:  The impact that the Fuel Conditioner has on microbial and fungal growth is described in detail in the article: “Why Bacteria Hate Magnets“.  The movement of the fuel through the magnetic field created within the Fuel Conditioner impacts microbial, bacteria and fungal growth preventing reproduction.

Second:  This same movement of fuel through the magnetic field breaks down the asphaltene that has agglomerated and puts it back into solution.  This is really how dark brown and black fuel becomes clear and bright, where the term fuel polishing came from.

Without a Fuel Conditioner, you do not have Fuel Polishing.

The Fuel Conditioner is the core component of every one of the Fuel Maintenance Systems we sell:

  • The TK Series Portable Tank Cleaning System
  • The FPS Series Compact Fuel Maintenance System
  • The MTC Series Mobile Tank Cleaning System
  • The STS Series of Advanced Automated Fuel Maintenance Systems

When installed in-line on the fuel line, the Fuel Conditioner works as the engine runs.  When used in conjunction with AFC Series Diesel Fuel Catalyst, contamination and sludge dissolves and the asphaltene clusters and solids are dispersed and returned to being in solution.  The AFC stabilizes the stored fuel extending its shelf life.  The results are “Clear & Bright” Fuel, improved filterability, optimal combustion and a clean fuel system. Degraded and deficient fuel is quickly restored to usable condition. With regular fuel polishing utilizing the AXI Systems that include the Magnetic Fuel Conditioner, the need to use chemical treatments, that present their own problems in their attempt to treat microbial contamination, is no longer needed, further reducing costs and maintenance.

Learn the Real Story of Bad Diesel Fuel.