Australia’s Diesel Fuel Quality:

Australia is known to have one of the worst qualities of diesel fuel in the developed world. When fuel samples have been tested, Australian diesel fuel has often contained more sediment, water and other contaminates than the maximum allowable tolerances set by vehicle manufacturers. There are many factors contributing towards our poor fuel quality, such as where our fuel is sourced from - primarily South Korea, Japan and Singapore. Travel distances which affect the time fuel is kept in storage, transporting the fuel both during importation into the country and then also when transporting the fuel to individual fuel stations and on top of all that, the poor quality of many Australian fuel storage tanks at individual fuel stations. The transferal of fuel from truck to tank can stir up sediment, rust and other contaminates that generally form at the bottom of the storage tank. Fuel also degrades in quality over time and in Western Australia we have no local refinery. At the end of the day, our poor fuel quality comes down to two factors time and travel distances.

Why is this a problem?

With older diesel vehicles, fitted with mechanical fuel injection systems, fuel quality and contamination wasn’t a large problem. The fuel systems of mechanically injected vehicles could tolerate some level of water or contamination within the fuel without serious consequence. Mechanically injected vehicles might run rough and inefficient until the contaminated fuel had left the fuel system, but they would generally continue to run unaffected and without damage afterwards. With the introduction of common rail fuel injection systems, this all changed.

Common rail injection was first introduced in the European market, fitted to passenger vehicles in 1997 by both Alfa Romeo and Mercedes-Benz. For the Australian market, most diesel passenger vehicles produced after 2006-2007 utilise a common rail fuel injection system. Common rail fuel injection revolutionised what turbo diesel engines could do. Due to the huge increases in both performance, driveability, a decrease in emissions and an increase in efficiency, the introduction of common rail injection systems caused turbo diesel engines fitted to passenger vehicles to explode in popularity. In real world terms passenger diesel vehicles now ran cleaner, quieter and more efficient.

So, what’s the catch? To achieve these significant improvements, common rail systems run far greater fuel pressures than the mechanical fuel injection systems, in some systems up to 30, 000 PSI. With far more advanced technology, came increasingly more expensive parts, with more precise tolerances. At these high fuel pressures and with these precise tolerances, the water and contaminates previously mentioned that are found regularly in Australia diesel fuel, well that is now a significant problem. Unlike a mechanically injected diesel system, water and contaminates running through a common rail system can destroy the fuel injectors, the fuel rail, the fuel pump and in the worst cases, even the engine. Potentially costing thousands to tens of thousands of dollars in repairs.
All diesel four-wheel drives sold in Australia come fitted with a fuel filter from factory to prevent contaminates from reaching the fuel injection system. However, the majority do not filter or capture water from the fuel. The factory filter is generally between 8 to 12 microns in size.
 
So, what’s the solution?
 
The most cost-effective solution, and cheapest insurance policy to help protect your common rail vehicle is a secondary fuel filtration system, we recommend the fuel manager. The secondary fuel filtration system works as an additional layer of protection, alongside your factory fuel filter. There are two methods of setting up a secondary fuel filtration system, post filter and pre filter. We always recommend a pre filter setup before your factory filter with a 30-micron filter which will capture any larger contaminates and filter out any water from the fuel. The water will then be separated into a bowl at the bottom of the fuel manager, which can then be easily drained. The filtered fuel will then flow into the vehicles existing factory fuel filter and then through the rest of the fuel injection system. This setup adds another layer of protection while leaving your factory filter as the last line of defence, the clear bowl also provides the ability to see whether there has been any water in your recent fuel. The other option is a post filter setup where the secondary fuel filtration system is fitted after the factory filter and generally uses either a 2- or 5-micron filter, which is finer than the factory filter.

We highly recommend the prefilter setup because it allows water to be caught and drained before reaching the factory filter and this setup allows the line of defence to be the finer factory filter. A prefilter setup also avoids the possibilities of fuel flow restrictions, due to how fine the filter needs to be on a post filter setup, there are the possibilities of creating fuel flow issues or restrictions.

Modern common rail injectors can cost between $450 and $750 dollars per injector, these prices are supply only and exclude the labour cost to install and code the injector/injectors. If a secondary fuel filtration setup captures water or contaminates that would have potentially reached the fuel pump, rail or injectors, then the fuel filtration system has already paid for itself.

United Fuel Injection supply and install a vast range of fuel manager kits to suit most common rail passenger vehicles sold in Australia. We also sell direct bolt on kits which are straight forward to install and come with everything required.