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Discussion Starter #1
HI ALL,
I HAVE JUST JOINED THE SITE TODAY IN THE HOPE SOMEONE CAN HELP ME OUT WITH A PROBLEMATIC ML270 CDI.........
THE VEHICLE CAME INTO ME LAST WEEK AND WAS SMOKING LIKE CRAZY FROM THE EXHAUST...I REMOVED THE INTERCOOLER TO TURBO HOSE AND THERE WAS A SIGNIFICANT AMOUNT OF OIL PRESENT SO I CAMR TO THE CONCLUSION THAT THE TURBO HAD FAILED.....
THE CUSTOMER SUPPLIED A SECONDHAND UNIT AND I FITTED IT....CLEANED ALL PIPES AND THE INTERCOOLER AND STARTED HER UP.....
AFTER A FEW MINUTES IT DEVELOPED A HEAVY KNOCK FROM THE ENGINE AND REDLINED ON ITS OWN!!!!!!.......AFTER IT CUT OUT I REMOVED THE INTERCOOLER HOSE AND STARTED IT AGAIN....THE KNOCK WAS MUCH QUIETER BUT I HAD OIL SPITTING FROM THE TURBO SO I SUSPECTED THE UNIT SUPPLIED WAS FAULTY....
I PERSUAUDED THE CUSTOMER TO HAVE A NEW UNIT AND THIS ARRIVED TODAY AND I HAVE FITTED IT.....BUT UPON STARTING AND AFTER A FEW MINUTES RUNNING THE KNOCKING IS BACK AND I HAVE AN INCREDIBLE AMOUNT OF THICK GREYISH SMOKE FROM THE EXHAUST.....HAVE DISCONNECTED THE INTERCOOLER HOSE AGAIN AND ALL SEEMS DRY....THE OIL LEVEL IS JUST UNDER THE MAXIMUM AND I HAVE CHECKED THE FUEL AND THERE IS NO CONTAMINATION....
I AM AFRAID TO LEAVE IT RUNNING FOR TOO LONG AS IT MAY REDLINE ON ITS OWN AGAIN!!!!!!!!!!.....
COULD ANYONE SHED SOME LIGHT ON A SOLOUTION TO THIS PROBLEM SO I MAY SLEEP AT NIGHT!!!!!!....
MANY THANKS IN ADVANCE........MARCUS........
 

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The engine redlined by itself because engine oil in the intercooler is fuel to a diesel engine. You experienced a "run away" condition that usually results in catastrophic engine failure.

Anytime you change a failed turbo you need to have all the turbo air tubes and intercooler flushed to get all the oil out...

Do a google video search of diesel runaway
 

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They supplied the part? What kind of warr. did you give them?
 

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I REMOVED THE INTERCOOLER TO TURBO HOSE AND THERE WAS A SIGNIFICANT AMOUNT OF OIL PRESENT SO I CAMR TO THE CONCLUSION THAT THE TURBO HAD FAILED
The "significant amount of oil" is why the engine ran away. When a turbo fails the presurized oil enters the exhaust and the charged air side of the system.

When a good turbo is installed it will use the oil that was sprayed into the intercooler and charged air lines as fuel. The intercooler could have several quarts of oil in it depending on the size. This is more than enough to destroy an engine

As a diesel has no butterfly valve in the intake it is like wide open throttle as long as it is getting fuel. The throttle on a diesel controls the fuel volume not the air volume...
 

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Discussion Starter #6
ml smoking hell!!!!!!

thanks for your replies everyone.....
i may have forgotton to mention that i have ran the vehicle with the intercooler pipes disconnected and still get the smoke and engine knock????
 

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ml smoking hell!!!!!!

i havent ran it off idle for long if im honest for fear of it happening........and the smoke at idle is still intense and thick greyish white and there is a slight knock from the engine......do you think i should run it off idle for a while and see????.....and if it does redline what do you think could be the fault????
regards
marcus
 

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The smoke at idle is still intense and thick greyish white and there is a slight knock from the engine.
Since they suppied the part......



You are going to have to rip the block down, to fix this. But stop running it, you're only making it worse.



Personally I think you bent a rod, still have good oil pressure, the last time you ran it?
 

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Discussion Starter #10
ml hell

just to clarify.....
we have fitted a brand new turbo from our usual suppliers so there unit has been discarded
 

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just to clarify.....
we have fitted a brand new turbo from our usual suppliers so there unit has been discarded
But wasnt it their turbo that dumped all of the oil into the combustion chamber?



Cant put a band-aid on a beheading. The damage was already done.


Do a pressure test on the cooling system, I bet you wont like what you see.
 

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ml smoking hell!!!!!!

hi all........
have checked cooling system and all is fine there.....used a dye to test for cracked block also and results came back all ok......
have removed the turbo to air intake hose and the egr and intake manifold were heavily coked in carbon and oil so left them for cleaning.....
i have now2 started the vehicle again and there is no engine knock and its idling and revving smoothly but there is excessive smoke coming from the metal canister which bolts to the side of the inlet manifold (its water cooled and i suspect its to do with the egr system).......and sthe smoke is greatly reduced from the exhaust......any ideas guys??????????
regards
marcus
 
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