Check your Diesel Generator Fuel

Regular checks of your generator’s fuel tanks are essential even if your equipment is properly maintained, regularly serviced and sited in a benign location.

As the diesel generator fuel in the tank get warm during the day and then cools at night a process called thermal expansion causes condensation to form.  The introduction of water can cause several problems:

  • Corrosion of metal tanks introduces particulates that damage fuel lines and engine components.
  • As water mixes in the fuel it encourages the growth of algae, which contaminates the diesel.
  • Excessive water ingress means that the diesel fuel may contain either water in solution or free water.  Both can reduce an engine’s efficiency and cause problems with filters, injectors, lines and engine components.
  • In cold weather the water can freeze, particularly in the fuel lines and filters.

You can make a quick visual check of your diesel to see if it looks hazy or it contains water droplets.  If water ingress has occurred then you will experience problems with erratic idling, cut-outs or excessive smoke from the exhaust.

One tip to prevent or reduce condensation is to keep the fuel tank topped up.  There are also a range of fuel additives to firstly remove algae and secondly to control diesel in water problems (through emulsification or de-emulsification).

If the problem is severe then free water at the bottom of the tank can be drained and/or the fuel can be cleaned and polished.

Hopefully you can keep your existing gen sets working free from water problems.

If you are looking for new or used diesel generators to supplement your back-up facilities then talk to us today.

Call freephone 0800 999 3303+44 (0) 121 5570270 or e-mail us on


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