Do Magnets Kill Diesel Bug?

Are magnets a reliable way to treat fuel problems?

We have many fuel polishing systems keeping diesel in prime condition for back up power applications in many data centres, hospitals and other critical applications.  But we are often asked “why don’t you fit fuel magnets?”

There is actually very little hard, trustworthy data to support the claims that magnets effectively treat any form of diesel contamination.  Some were originally introduced claiming that they “killed diesel bug” others were developed with the aim of altering the molecular structure of fuel.  There is plenty of opinion and anecdotal evidence but we have yet to see a study that proves any lasting, positive effect.

What we do know, is that a study by the Australian Department of Defence found that a particular brand of fuel magnet had no discernible effect on diesel bug and other contaminants, and actually introduced more contamination into the fuel as the magnets eroded, causing an increased risk of filter blockage.

Other studies have suggested that, while magnets can slightly disrupt the growth of microbes, this is only a temporary state and once clear of the magnet field they revert to normal growth and multiplication – none are killed.  The same is true of the formation of wax crystals –  when subjected to a magnetic field there is some softening of the crystals but once free of the magnetic effect for 14 seconds the effect is gone.

More worryingly, from our own experience we also know that, where fuel deliveries have high quantities of iron – which can be common  – magnets can actually induce filter and fuel system blockage by causing iron particles to agglomerate together.  Certainly not what you want in a critical back up power application.

We recommend – Efficient fuel polishing, using world class filtration, to remove particles and water.  Keep the water out and you keep the bug out.  If you do get diesel bug, clean the tank or use a biocide – and keep polishing!

If you would like to know more about IPU Fuel Conditioning Solutions, call us on 0121 511 0400 or email