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Donaldson filters ensure this bulk diesel storage facility pumps clean fuel.

Keeping diesel free of contaminants is ultimately about filtration. Much has been written about the subject in past FleetWatch diesel reports but as injector tolerances get finer and slack housekeeping habits continue, the need for sophisticated filter technology increases. Mariette Jacobs, Marketing Manager, Donaldson Filtration Systems sheds light on the subject.

Today's engines are built to more stringent specifications and finer tolerances. Fuel systems, pumps and injectors require cleaner fuel to achieve better combustion and lower emissions. The "Common Rail" fuel systems prevalent in today's modern engine have extremely fine tolerances and operate at high pressures necessitating the need for a sophisticated solution. That's why the latest advances in filter media can make the difference between engine power and engine problems.

The South African environment has extreme variances in temperature giving rise to condensation during the storage of fuel not to mention the high levels of contamination in the air. Fleet operators can buy clean diesel only to find that it becomes contaminated in storage, be that in the vehicle's tank or bulk storage. 

Engines thrive on purity
Donaldson Filtration Systems recognized this and developed the Donaldson Fuel Manager utilizing the latest technology available. This product utilizes synthetic media which facilitates finer filtration without affecting fuel flow. The media is also treated to repel free and emulsified water thereby ensuring that the engine only sees pure clean diesel.

The problem with water contamination is that it lowers the lubricity of the fuel and promotes oxidation. This not only affects the internal workings of the engine, the pistons, bearings and so forth, but also damages the injectors and injector pumps. What is more, water in diesel promotes the formation of highly corrosive acids in the combustion chamber. Water mixed with diesel in a fuel tank also supports biological growth and generates organic contamination, which if it becomes severe, can accelerate the blocking of a fuel filter water separator. 

When one thinks of millions of these particles being forced through injector systems, it is not that surprising that many injectors fail prematurely. Solids create an irreversible problem, for once the injector has been damaged, there is no adjustment to compensate for this.

Frequent replacement
Most vehicles on South African roads use standard filters in the range of five to 15 microns. With the recent introduction of higher performance diesel engines, high-efficiency filters, in the range of two to five microns, have been introduced in response to the higher pressures and tighter tolerances of modern injector nozzles.

Considering the general cleanliness levels of diesel in South Africa, these filters will tend to block more rapidly, leading to the need for filter replacement sooner than the prescribed maintenance intervals. 

Added benefits
Customers who have fitted the Donaldson Fuel Manager have seen that apart from prolonged pump and injector life they are seeing other unexpected benefits to clean diesel. These include improved fuel consumption as well as less wear on power train related components as the engine is running at its full potential hence less change downs and less wear and tear.

In the face of a severe contamination problem, there are solutions that can be applied to on-site bulk fuel storage. The whole philosophy at Donaldson is that the company sells filtration solutions, not filters alone. We like to advise companies upfront about their filter solutions and how to reach the right levels of cleanliness. Donaldson has a bulk diesel cleaning programme, which is ultimately a cheaper solution.

In a nut shell, the Donaldson Fuel Manager, in conjunction with Donaldson Filtration's bulk storage solutions such as breathers and delivery filters, assists customers where it counts; by lowering their operating costs and improving their all important bottom line!