Diesel Fuel Management
is an Important Part of
Diesel Generator Service

The need for reliable backup electric power is too important to leave to chance. Emergency power generators that rely on diesel fuel are at constant risk of unexpected failure due to clogged fuel filters when the diesel fuel is allowed to degrade and contamination occurs. Including the monitoring the condition of the diesel fuel and the fuel storage tank is critical whenever diesel generator service is performed.

Diesel Generator Service

The standard in the power generator industry is to simply run the backup generator system periodically, maybe once each month, for 30 minutes or until it reaches operating temperature. This is not enough time to allow the diesel fuel to circulate to achieve meaningful filtration. The diesel fuel is, however, subjected to injector pump pressure and extreme heat that warms the fuel returning to the storage tank and encourages condensation to form in the tank bottom providing an attractive environment for microbial contamination to thrive. Fuel filters are changed during normal oil changes, typically twice per year. The amount of run time for the fuel is not enough to allow contaminant build-up on the filter to reveal to the maintenance personnel that there is a diesel fuel contamination problem. Biocide additives are repeatedly added to the same fuel to deal with microbial activity, but this process accelerates fuel deterioration causing solids and debris to settle in the tank. Some protocols require fuel samples to be tested for microbial and fungi activity, but results show a false negative in many instances due to the presence of the residue of the biocide chemicals. Fuel quality, it is mistakenly assumed, is being maintained.

The Service Process is Part of the Problem

As engines are tested, the diesel fuel is continuously re-circulated and exposed to extreme pressure and heat, which results in the agglomeration of asphaltenes, the high carbon content, heavy end fuel molecules. This process leads to the formation of larger and larger clusters and solids, which are very difficult to completely combust. These solids may grow so large that they create larger fuel droplets, too large for efficient combustion to occur.

More than 90% of the debris and the sludge in our tanks is organic material, fuel and oil breakdown residue. In most cases, this debris is acidic and not good for your engine. It causes corrosion in injectors, pumps and storage tanks. Even though microbes may cause and accelerate the process of fuel degradation, it should be clear that the waste products causing the problem are not the microbes but fuel components which have formed solids.

Its not until the power goes out and the generator runs under full load that the extent of the problem is evident.  The generator shuts-down due to restricted fuel flow the result of a clogged diesel fuel filter. Repeated filter changes treat the symptom, but then adding fuel stirs up debris in the tank and the problem continues.

Treating the Symptoms

Maintenance personnel without knowledge of what is really going on add additional filters, and pour in more biocides, only treating the symptoms of the problem. Other “filter cart” systems available on the market claim to polish the fuel, but just filtering does not address the fuel deterioration problem. Without the AFC Series Fuel Catalyst, Stabilizer and Tank Cleaning Additives the debris attached to the tank walls and tank bottom are not cleaned. And without the LG-X Series Magnetic Fuel Conditioner being included in the treatment, the fuel degradation is not addressed.

The diesel fuel stored for standby generators must be periodically treated with one of the AFC Series Diesel Fuel Catalyst to stabilize and restore fuel quality, dissolve and disperse sludge and slime, remove carbon build up in injectors and the combustion chamber, and extend engine life.

Fuel that has been in storage will become dark and degrade. The agglomeration of asphaltines in the fuel must be polished and dispersed to put these fuel components back into solution (restoring the Clear and Bright appearance of the fuel) at least every six months with an application-specific FPS Series Fuel Polishing System or, where many tanks are to be treated, with a MTC Series Mobil Tank Cleaning System. Large installations should incorporate a dedicated STS Series Automated Enclosure Fuel Conditioning and Tank Cleaning System.

Maintaining Optimal Fuel Quality

Diesel Fuel maintained by AXI Total Fuel System Management has optimal fuel quality: