What is 'Diesel Bug'
Diesel bug is not a single species of microbe. It can comprise a collection of bacteria, yeasts and moulds. It can exist even in fuel that is quite clean, but at low levels. If it does not enjoy suitable conditions to enable it to flourish, there is little to worry about, as minor contamination will be filtered out as the fuel is drawn through to the engine.
'Suitable conditions' essentially means the presence of water, because the microbes live and multiply on a fuel/water interface. They live and reproduce in the water, but feed on the nutrients in the fuel. Given the presence of water, warm or humid conditions will also help them to propagate. The number of bugs required to pose a problem is many millions, so the level of contamination is measured as a logarithmic power in colony-forming units (CFUs). 'Clean' fuel will have a rating of up to a few thousand (2x103cfu/lt), light contamination which is enough to cause a problem is up to a couple of million (2x106cfu/lt), while heavy contamination will be up in the tens of millions (1x107cfu/lt).
Motor Boats Monthly "Best Value" Product - Biobor JF
Used widely in industry, this product has a good reputation for getting the job done, albeit slowly. Our own tests backed this up, with little obvious immediate effect but good results over the longer term.
However, it kills off the bug only in the fuel but not in the water, making recontamination likely if you don't keep up the preventative dosage. It comes in a handy-sized bottle with an integral measure.
Shock treatment 20ml per 100lt.
Preventative dose 10ml per 100lt.
Price £8.48 for 235ml (treats 530gal).
Preventative dose cost per 100lt of fuel £0.36.
- Specially formulated for diesel and jet fuel
- Considered the industry standard in killing microbial growth
- Recommended by airframe and equipment manufacturers around the world
- MIL-S-53021A
The content of this page is taken from the article 'Beating the Bug' wriiten by Mark Turley in the November 2002 issue of Motor Boats Monthly Magazine.
A full copy of the article is available on request which includes full details of all of the products tested and the comparative results in .pdf format.
Back to Diesel, Fuel and Marine Biocide Page.
