Tech Tips

 Fuel Filter Tech Tips

To help maintain the serviceability of your fuel filters then you should consider the following:

  1. Utilize good, clean, quality fuel.
  2. Eliminate possible sources of contamination at bulk fuel-storage facilities.
  3. Monitor fuel-storage for water, bacteria or fungus. Treat appropriately with preventive maintenance.
  4. Drain vehicle fuel tanks on a regular interval. Remember, this should be done at least 24 hours after the vehicle has been idle.
  5. Do not blend used oil with diesel fuel. It can cause increased wear of injectors and plug filters, and form carbon deposits on piston tops.
  6. To help minimize the condensation and water accumulation in vehicle fuel tanks, top off with fuel at the end of the day.
  7. Good quality fuel filters are designed to last beyond the recommended change interval. If a fuel filter does not last as long as the change interval, it can generally be attributed to excessive contaminants and/or water. Always remember to drain fuel/water separators periodically

Cleaning Air Filters

Some vehicle owners and maintenance supervisors, concerned with lowering operating costs, elect to clean and reuse heavy-duty air filter elements. However, this practice is not recommended as it puts your equipment and your investment at risk.

Several other factors should also be considered before deciding to clean or wash a heavy-duty air filter. These factors include:

  • Many contaminants, such as soot and fine particles, are difficult to remove from the filter media.
  • Cleaning methods cannot restore filters to like new condition and may cause damage to the filter media.
  • Cleaning a heavy-duty air filter reduces the life of the element. This effect is cumulative each time a filter is cleaned and reused.
  • Because of the decreased life of a cleaned air filter, the filter must be serviced more often, exposing the air intake system to potential contamination.
  • Extra handling of the filter during the cleaning process, and the cleaning process itself, may damage the filter media, exposing the system to contaminants.


Inner (or secondary) elements should never be cleaned as these filters are the final barrier against contaminants before air reaches an engine. The standard rule of thumb is inner air elements should be replaced once every three changes of the outer (or primary) air filter. This may be reduced for more extreme working environments.

The best way to get the most out of a heavy-duty air filter is to use an air restriction gauge, which monitors an air filter’s condition by measuring the air flow resistance of the air intake system. A filter’s useful life is established by the equipment manufacturer’s recommended restriction level.

Using a new filter with each filter service, and using that filter to the maximum capacity determined by the OE recommendations, is the most cost effective way to protect your equipment.

Understanding Micron Ratings

A micron is a unit of measure in the metric system equal to 1 millionth of a meter in length (about 39 millionths of an inch). The average cross-section of a human hair is 50 microns. The human eye cannot see anything smaller than 40 microns in size.


50 microns – Diameter of a human hair
40 microns – Lower limit of visibility of a human eye
25 microns – White blood cells
8 microns – Red blood cells
2 microns – Bacteria

A micron rating is used to indicate the ability of a liquid filter to remove contaminants by the size of the particles. It is important to remember that a micron rating without an associated beta ratio or efficiency does not fully describe the performance of a filter.

A filter that has a rating of “10 micron” has some ability to capture particles as small as 10 microns; however, because there is no single accepted way to measure and describe the size and amount of contaminants a filter can hold, you need more information. For a micron rating to be truly useful, you must know the filters’ removal efficiency of the specific particle size in question. There are several variations of micron ratings, but the two most common terms used are nominal and absolute.

Nominal Micron Rating – expresses the ability of the filter to capture particles of a specified size at an efficiency between 50% and 90%. For instance, a nominal rating of 50% at 10 micron simply means that filter captures 50% of contaminants 10 micron in size. Keep in mind that nominal micron ratings may range anywhere from 50 – 98.6% efficient at removing a specific particle size.

Absolute Micron Rating – means that the filter is capable of removing at least 98.7% of a specific size particle. This rating is
determined through a single-pass or multi-pass test in which fluid containing measureable particles is passed through a flat sheet of filter material. Particles that pass through are measured and counted. This rating is more informative than the nominal micron rating.

Hydraulic Filters

80% of hydraulic system component failures are caused by excess contamination in the hydraulic system.

Hydraulic or fluid power systems can be found on a variety of equipment. Systems range from the relatively simple power steering and transmission of trucks and buses, to the more complex systems found in agricultural, construction, marine and mining applications.These systems contain precision-machined components that are very sensitive to wear from abrasive particles and need to be protected.

Contaminants can enter hydraulic systems from a number of sources:

  • Built-in from the manufacture of the system and its components
  • Quality and cleanliness of the hydraulic fluid used and the filling process
  • Operational ingress where rams and cylinders are exposed to dusty atmospheres and missing ineffective tank breathers
  • System generated wear particles

Eliminating contaminants from the onset is preferable through effective maintenance processes. Here at Bransby Components Ltd we offer a comprehensive range of replacement suction, return, pressure and offline hydraulic filters to cover a variety of applications.