ML 270 cdi won’t start help !!!!

ML270marc

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Hi I hope someone can assist, we had a strong smell of diesel when starting so on inspection noticed fuel coming from the high pressure pump. I have replaced the pump and all the HP and LP fuel lines as the seals were perished. It now won’t start no matter how much cranking to the point of flattening two batteries. Anybody have any idea’s ?
Is it possible I have the HP pipes on the left of the pump the wrong way round. The pipe with the T piece is on at the front and the one that goes to the back of the rail is at the back of the pump closest to the engine.
 
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om613

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Easi-Start (ether spray).
You should have just done the LP lines first, it is usually their O rings.
HP lines rarely leak.
 
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ML270marc

ML270marc

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Both the HP line white seals had perished , fuel seems to get as far as the HP pump but goes no further. Will easy start help pull the fuel through ?
 

Steve@Avantgarde

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First question...

Does it have fuel pressure of 150bar when cranking at the injector rail...??

If it has no fuel pressure it won't go no matter what. Don't guess at it, measure it.
 
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ML270marc

ML270marc

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First question...

Does it have fuel pressure of 150bar when cranking at the injector rail...??

If it has no fuel pressure it won't go no matter what. Don't guess at it, measure it.


Not sure, that’s something I haven’t checked but good point. Just checking though as described above are the pipes in correctly before I go further.
 

om613

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2 LP lines connect there... and they regularly leak.
Internal leaks from the pump much less common. And will cause running / starting issues, aside from leaks!
So that's where to start.
Both the HP line white seals had perished , fuel seems to get as far as the HP pump but goes no further. Will easy start help pull the fuel through ?

Those 'seals' are white foam, they don't do much.

Yes, the engine pulls it through. Saves the starter and battery.
 
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ML270marc

ML270marc

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She’s Alive!!!! I would like to say a big thank you for all your help problem now resolved, totally my fault school boy error not labelling the HP pipes when I took the old ones off.... got them the wrong way round. On the plus side she now has all new pipes and pump which were leaking and a new thermostat so she is getting to temperature and I’ll be able to smell leather and not diesel.
 


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