How to Test For and Prevent Diesel Bug in Contaminated Fuel

It can be hard to know if water has already made its way into your fuel tank, so let’s look at how to identify diesel bug, how to test for it, and how to prevent it.

Before using a diesel bug test kit, you can look out for the following symptoms of fuel contamination and diesel bug. The most obvious is a brown sludge or sediment at the bottom of the fuel tank. Black smoke or an unpleasant smell may come from the exhaust after refuelling, along with increased emissions. Another symptom to look out for is blocked filters, and filters that are getting blocked faster than they usually do. Fuel consumption may rise, and starting the engine could become problematic if diesel bug is in the fuel.

Once fuel has been contaminated by water, the spores and bacteria will germinate, feeding off the water. Diesel bug can then multiply very quickly, doubling in size every 20 minutes. It can take no time at all for a thick sludge to form and cause havoc in the engine or fuel tank, so you need to act fast.

The quickest and easiest way to test for diesel bug is to use a FUELSTAT Fuel Contamination Test Kit. The single-use test kit is designed for immediate use wherever the fuel is stored or used and provides reliable and accurate results in just 15 minutes. This is significantly faster than other market fuel tests, which can take up to 72 hours. No additional equipment is needed—just a FUELSTAT diesel fuel test kit and 4 drops of fuel.

This type of diesel bug test works like a pregnancy test for fuel, looking for markers of harmful microorganisms in fuel systems, instead of human hormones.

The microorganisms and microbes known to contaminate diesel fuel include bacteria, fungi, yeasts, moulds and hormoconis resinae, which are all detected by the markers in the fuel test kit. As this diesel fuel contamination test kit detects activated germinating spores in the fuel, if the test result is positive, it typically means the fuel contains water, which is feeding the diesel bug.

Regular diesel testing of at least once a year is advisable, especially in warmer regions where fuel is exposed to humid conditions. For areas prone to microbial contamination, testing every 3 months is recommended. Detecting diesel bug and fuel contamination from water early on is the most cost-effective solution, with prevention involving prompt water removal.

The solution depends upon the extent of the diesel bug problem, which can be dictated on the FUELSTAT diesel bug test. The fuel contamination kit from FUELSTAT gives 3 level indicators of results - negligible, moderate, or a heavy level of contamination, as well as which group of microorganisms are present in the fuel.

If you have a bad case of contaminated fuel causing diesel bug, your fuel may need to be removed and be put through a fuel polishing system by a professional and placed into a clean tank afterwards.

Diesel bug grows in fuel when there is water present, so preventative measures such as installing a CTS fuel conditioner unit or an Aquafighter fuel tank water absorber into the tank can stop diesel bug from growing from the source.

Now that you know how to identify and test for diesel bug in your fuel, you can prevent and avoid it, ensuring fuel contamination from water is dealt with before it causes a serious issue.