What is diesel bug?

What is Diesel Bug?

Diesel Bug

The dreaded diesel bug! It can stop your engine flat – so just what is it?

If your boat has been subject to variations in weather and temperature (and almost all of them have!) or your fuel has been stored for anything longer than a few months without usage, there is a danger of Contamination – Bacteria and ‘The Diesel Bug’.

Diesel has an inherent bacteria and when water is added this bacteria is able to breed.

This ‘bug’ will form a layer between the fuel and the water and as it breeds it produces waste which is usually evident as black or dark lumps – a slimy mass – which block filters.

Diesel Bugs are in fact microbial organisms which come in three main varities: bacteria, yeast and moulds.

Diesel is an organic fuel, so when water is added to the the mix, it provides an ideal environment for this cocktail of microscopic fungi, yeast and bacteria to feed and grow. All tanks contain water, either from the air or condensation. When the water accumulates and the temperature (anything above 10 Celcius) and the humidity are right – breeding begins!


EU directives

With new EU directives leading to the increasing addition of biofuel into our diesel the problem is predicted to get worse and worse. Biofuel absorbs more water, the water falls to the bottom of the tank and encourages the bug.

This slimy mass at the bottom of your tank will clog up the filters and lead to expensive damage to equipment, with breakdowns in power supply.

Bacteria cells can multiply at a rate of 2 million times in 24 hours under the right conditions. After breeding the ‘bug’ dies within 48hrs, falling to the bottom of your tank where the remains build up as the slimy sludge.


What is the Best Solution?

We cycle the fuel through our machine where it is cleaned and conditioned, removing as much of the water, contamination, bacterial growth or biomass (‘Diesel Bug’)  as possible. We return the fuel to your tank re-optimised and ready for use. We will sometimes add a special fuel catalyst which will help to inhibit the growth of the Diesel Bug biomass.

The Dangers:

  • Clogged filters
  • Slimy build-up
  • Excessive smoke
  • Algae or fungi
  • Sludge or waxy deposits
  • Hazy/misty fuel
  • Smell of ‘rotten eggs’
  • Sputtering
  • Frequent filter changes
  • Corrosion of the engine parts
  • Damaged seals and gaskets
  • Reduced power from the engine
  • Sudden breakdowns!

Contact us today to find out more.