Generator Smoking

Generator smoking when running means that there are issues to be fixed.

Generator smoke upon starting up, is usual, as the diesel fuel in the cylinders is burned off in the first few seconds of operation and then should clear immediately thereafter leaving an almost clear emission.
You may also see some additional smoke when a heavy load is dropped onto the generator and the generator adjusts its fuel consumption to provide the additional power required to support the new load. Then again, the exhaust smoke become translucent, virtually invisible.

In normal use a generator should not produce continuous visible smoke from the exhaust silencer.

Should your diesel generator smoke be visible, then the causes of the smoke can usually be narrowed down by its colour, for example:-

  • BLACK SMOKE– poor diesel combustion caused by an air/fuel ratio imbalance
  • BLUE SMOKE – oil entering and burning in the combustion chamber
  • WHITE SMOKE – fuel isn’t burning correctly and is passing through the engine and the exhaust unburnt/not used.

How to fix smoking issues:-

  • BLACK SMOKE– adjust the fuel lines and fuel input. Replace the fuel filters and also replace the air filters. Check the quality of the fuel because dirty fuel & contaminated fuel will be a major first option to fix before checking our other suggestions.
  • Next check the injectors for replacement due to age and contamination.
  • BLUE SMOKE – replace the head gasket and any gasket/seal around the fuel filters and the oil filters as soon as possible. Failure to replace will cause major generator failure and costly replacement of parts.
  • WHITE SMOKE – Check the fuel supply and adjust the fuel to allow less fuel into the diesel engine. Also check for water leaks that may have found their way into the fuel tank or engine block. Tighten jubilee clips around hoses. Check hoses.

Click the video below to see how generator exhaust smoke should look like:-


Regular service & maintained generators by PowerContinuity never smoke!
Call 0854 055 8455 for any further help and advice

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