Established 1970
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The Answer is in the Smoke

We can generally understand what is wrong with a diesel engine by the colours of smoke emitted from the exhaust. There are three basic colours - black, white and blue.

Black Smoke

  • This is due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air (oxygen ) a few things to look for :

  • Faulty injectors, defective or incorrect atomisers. (injectors need attention at about 100.000 to 120 000 Kms)

  • Faulty injector pump     

  • Incorrect fuel injection pump timing or incorrect valve timing.

  • Poor engine compression

  • Dirty air cleaner

  • Turbocharger or intercooler faulty, poor boost pressure

  • Problems within cylinder head, valves clogged up due to faulty EGR (exhaust gas recycling unit)

  • Exhaust system restriction

  • Defective "Thermostart" (Cold starting aid)

  • Incorrect valve clearances.


White Smoke

Normally means that the fuel injected into the cylinder is not burning correctly.  The smoke will burn your eyes.

  • Engine/pump timing out

  • Fuel starvation to the pump causing the pumps timing not to operate correctly

  • Low engine compression

  • Water/petrol in the fuel     


Blue Smoke


The engine is burning engine oil

  • Worn cylinders or piston rings

  • Faulty valves or valve stem seals

  • Engine over full with engine oil

  • Faulty injector pump/lift pump allowing engine oil to be mixed with the diesel

  • Incorrect grade of oil used.

  • Poor compression










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