the problem

Diesel bug microbes thrive wherever there is food and water. Marine diesel fuel systems are therefore ideal habitats for bacteria, yeasts and moulds. The trend towards biofuels is creating pressure for reducing sulphur and increasing biofuel content. Sulphur kills bugs and biofuels contain additional water, so the changing fuel specifications are set to make marine diesel fuel an even more bug friendly environment. The diesel bug when grown unchecked can block fuel filters and stop engines. They are so corrosive that they can eat through even stainless steel fuel tanks, over time.

the test

All you need is 10 minutes, a flat surface, a pair of latex gloves & a 200 ml sample to discover if diesel bugs are living in your fuel. The easy to interpret, pregnancy style kit gives a negligible, low or high reading. This clearly indicates the vessel’s diesel fuel system status, and what action to take, if any.

the solution

A multi-disciplinary approach to fuel hygiene is the key to avoiding the inconvenience and cost of diesel bug contaminated fuel system. Good fuel hygiene entails implementing an ‘appropriate to risk regime’. Risk is increased in hot, humid conditions, especially where diesel fuel comes from a less than reputable source. The regime should consist of regular draining of water, including the hazy fuel layer, at least annual bug testing, followed by an appropriate fuel system treatment. Appropriate treatments range from do nothing to completely replace the whole system, with tank cleaning, biocides and fuel polishing included in the intermediate options.