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In general, the fuel quality of New Zealand delivered fuel is of acceptable but varied standard. The regulations require that it meets given standards - and it does. However, that does not mean it is contaminant or water free.

For Diesel

Over 80% of all diesel and fuel system issues are caused by contaminants including water in the fuel. Contamination can affect a wide range of systems and can accelerate component wear and decrease service life. Even if no immediate failure occurs, contamination can dramatically decrease operating efficiency, and worn components in turn contribute to inefficient operation, higher operating temperatures, and poorer economy.

Modern diesel in New Zealand is following the standards set in Europe. Progression to ULSD (Ultra Low Sulphur Diesel) some with ever increasing biofuel percentages have created several challenges to industry in recent years. Bio-Fuel blends are increasingly hygroscopic based on blend % which enables them to absorb greater amounts of moisture. This in turn leads to higher levels of micro-biological activity which cause serious issues to fuel systems.

So why has this become a greater problem now?

Sulphur, which is being eliminated for emissions reasons, is a natural antibacterial agent and provided a degree of lubricity to the fuel.

Microbial spores can be easily introduced from the fuel source and from the air (condensation). Together with small amounts of water in the fuel, this becomes a breeding ground for Diesel Bug (in it’s many forms)

Fuel hygiene is ever more important, the containers you use, the filters you use and care you take tapping off free water, any treatment you do, all affect the condition of the fuel, and hence the performance of the engine, economy, injector pressure and operating temperature. These factors cumulate in the most important outcome of cost per hour to operate / productivity.

We are continually surprised at operators who have $100k equipment who do nothing, to protect their fuel supply. At a rate of mere cents/litre, they can have surety and the payback is far greater than the cost.

Say for example, an operator of a digger, uses 200L per day, at a commercial rate of around $0.03/L that would cost $6 in treatment!

The same as 1 ½ coffees!

So what will treatment protect him from:

  1. Remove water from the fuel (not getting into injectors)

  2. Dissolve sludge / eliminate diesel bug

  3. Prevent fuel system corrosion

  4. Extend component service life

  5. Diesel oxidation

What other benefits?

  1. Reduced operating temperature

  2. Improved economy

  3. Cleaner emissions (reduced particulate smoke)

  4. Better torque

In all cases, we support the best filtration possible, but further than that, cost of maintaining a treatment regime is negligible compared to the benefits gained.

A most common statement would be that they use / turn over so much fuel that there is no time for bug to grow.

That may be correct, but there could still be water or other contaminants in the fuel? Treatment will reduce that likelihood. The less water that gets to injectors the better to extend injector life and improve performance.

Another statement could be that we never have any problems.

Also could be true and why should they still maintain a treatment? As insurance, and there are different paths you can take, such as improved filtration which we support.

However Common Rail diesels run at higher pressure and therefor have smaller tolerances for contamination

So what treatment are we talking about?

There are multiple treatments you can find from various retail and whole sale suppliers. They are NOT all the same, nor are they all as effective. And there is a wide variation in price. Do your homework.

Chemically there are two forms – Biocide and Non Biocide.

Biocide, like RoundUp will kill any bug that it comes in contact with, but what if there is sludge? They don’t penetrate sludge or necessarily dissolve the sludge. Plus don’t forget, that this is a product in your fuel and so it will get burnt in the combustion process, so will end up in your exhaust?? How toxic is that? Why are some countries in Europe moving towards banning biocides?

Second is Non Biocide. Non Biocide typically work, not on the bug, but on the environment the bug needs to live in. Bug requires diesel, oxygen and water to survive. Can’t do anything about the diesel and oxygen, so eliminate the water and over time you will eliminate the bug. Right? Were it so simple.

Typical Non Biocides are based on detergent function. In other words, they break the surface tension of the water which is then absorbed into the fuel and gets burnt away as steam.

We DISAGREE with this process. On non common rail engines, that might have been fine for the injectors at lower pressure, but with the finer tolerances and higher pressures of common rail, all water should be removed before it gets to the injectors. Coalescing filters do much of this, but proper treatment, with FuelRight, will ensure most water is removed. FuelRight causes water to agglomerate (molecular water particles get bigger) and makes it easier to get filtered away.

Fuel360 Diesel treatment tablets also work this way.

Most Non biocides have no function is dissolving sludge. Sludge itself is not the bug but a by product of the bug. If the sludge slowly starts to break up in your tank, it gets agitated gets drawn up into the fuel system. Hopefully it won’t block the filter, but more likely it will.

Diesel Storage tanks

Please see our next article on issues in relation to longer term storage of diesel.

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