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Discussion Starter #1 (Edited)
in my job they continualy send us on various courses to keep you update on mechanical and electrical issues..........not a bad thing but wish they'd leave it to the younger ones lol
anyway here is an abstract taken from one of these courses and may be useful in evaluating probable symptoms

The Answer is in the Smoke

We can generally understand what is wrong with a diesel engine by the colour 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 (injectors need attention at about 100.000 to 120 000 miles)
  • Faulty injector pump
  • Dirty air cleaner
  • Turbocharger or intercooler faulty....inc pipe work
  • Problems within cylinder head, valves clogged up due to faulty EGR (exhaust gas recycling unit)
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
  • Turbo seal failure & coolant entering the combustion process
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
 

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And black smoke is often down to leaky pipework on the feed from the turbo to the inlet manifold via the intercooler - lots of places for it to split, wear or come loose.
 

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Discussion Starter #6
white smoke is also turbo seal failure & coolant entering the combustion process..
Hi aerojon have added to list m8:)

have excel document would like to insert gives more in depth reference to particular area's e.g you look at what smoke you have and symptoms and it cross refs to drop down box giving poss cause more in depth e.g turbo/wastegate etc etc
how do i go on putting such a table into a thread...................when i try it end up all over the place m8 any ideas:)
 

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Discussion Starter #8
BTW, Red, white and blue smoke all at the same time means that the Red Arrows just went past.
tony if i had one of those engines in my car wouldnt care what colour smoke it produced.............could be pink lol:crazy:

it does mention turbo/intercooler but will had check pipes for those not so experienced and simple thing to check:thumbsup:

as just said to jon have a excel sheet thats goes more in depth but cant seem to insert lol
 

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Discussion Starter #9
I am thinking of making this a sticky but where to put it....
up to the 3 of you mate good idea though................i want to add excel document as well but could be done laters and you can add to it if you make sticky.......................maybe one in each section as applies to all varients dont know mate what you think

just thought be useful thats y i posted in this section not just 9-3
 
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