Fuel Fix

Contamination in fuel is far more common than most people realise!

The two most common types of fuel contamination are; water and fungal growth.


Sierra’s Fuel Fix is a highly concentrated additive for the elimination and control of bacteria, fungi and water contamination in fuels. Utilising the latest in microbiological controls and surface active agents, water and biological contamination is harmlessly dissolved and dispersed into the fuel, and subsequently burnt off. Bacteria and fungi such as the common air borne spore Cladisporium Resinae appear as dark “sludge” like particles in the fuel reservoir. At their worst this “sludge” can amount to large lumps or mats. Unlike the many biocide treatments that are on the market that are only designed to kill bacteria, not remove and are of no use in removing water, Fuel Fix will remove the entire problem.

Fuel Fix can be safely used with diesel engines that run a particulate filter, in fact it will improve the efficiency of particulate filters, by dissolving any occurrence of the diesel bug.

Fuel Fix will not affect seals, hoses and fittings within the fuel system. Regular use will eliminate problems associated with condensation, and prevent further biological growth from occurring. This will give rise to;

Improved fuel economy

  • Smoother acceleration
  • Improved power
  • Improved fuel flow (especially through filters and injectors)

Left untreated, moisture in the fuel tank will eventually cause corrosion, leading to even more problems.


An initial dosage of 2 litres for every 1000 litres of fuel is recommended to thoroughly purge the fuel system of all contaminants. Regular subsequent dosage can then be reduced to as little as 1 litre for every 4000 litres of fuel. At this level of 1:4000, fuel quality will be maintained, condensation will be absorbed, and biological growths will be prevented.

If necessary, a maximum dosage of 5 litres may be added for every 1000 litres of fuel, where bacterial/fungal growth is inhibiting the flow of fuel through the system.

In all cases, Fuel Fix should be added prior to the addition of the fuel.

Since Fuel Fix will attack the existing ‘bug’ that is present, initial dosing will require more frequent cleaning/replacement of filters in the system to avoid blocking. Ensure that all efforts are taken to drain high levels of water first (where possible)


  • Appearance Dark Green Liquid
  • Specific Gravity 0.95
  • Flashpoint 176° C
  • Viscosity Approx 18 cPs
  • pH (1% aq. soln. ) 6.0-8.0

The dark sludge in this fuel sample is Cladisporium Resinae(fuel bug) which can grow at an alarming rate, clogging injectors and filters.

Counter Display “One Shot” Fuel Fix

Display boxes of 32 x 50ml are available now. Each bottle will treat up to   200 litres of Diesel. A great way to try Fuel Fix with minimal outlay.

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