Injector Problem W124 300TD.

chastrain

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Hi, i have what seems to be a water leak around the injector housing/head, have shown this in the enclosed pic/attachment with a yellow arrow pointing to the problem area, with the engine running.. from what i can make out it seems to be bubbling water. Not sure whether this is coming from injector housing or perhaps and from what i've read could be a perforated head ?.

The green arrow points to fuel leaking on/around the injector and isn't coming from the fuel return pipe.

Many thanks for your help :)

Ps, a previous problem with gearbox jerk was solved with a transmission fluid top-up, was above min, which 'i thought' was an ok level, so took it to max. Thanks to those that helped
 

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roadhog

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I realise you say it's not coming from the return pipe but that should still be your first port of call followed by a thorough clean and degrease of the area. For the few pennies that'll cost it will eliminate them once and for all. You may even be pleasantly surprised. :)
 
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chastrain

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I realise you say it's not coming from the return pipe but that should still be your first port of call followed by a thorough clean and degrease of the area. For the few pennies that'll cost it will eliminate them once and for all. You may even be pleasantly surprised. :)

thanks hog, i don't believe it is (green arrow), have checked thoroughly, dried it out etc fuel seems definately to be coming from the injector itself.
As for the bigger problem (small dark evil hole giving bubbling water by yellow arrow ) any ideas ?.

T^hanks :)
 

roadhog

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My return lines were past their best and a couple of them were leaking fuel down the injector. The evil little hole you're referring to was bubbling on mine as well but only on the ones where the fuel was leaking. New lines, no leaks, no bubbles. :D
 
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chastrain

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Is the engine losing water?

Cheers number, that's the place i looked first on the discovery... and no or at least not noticeably so, there's not a lot of water coming through, it's at the base of the first injector, have the water to radiator running in just beside it, as you'll know :)

thanks hog, though i believe it's water ? (evil hole-yellow arrow)
 
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chastrain

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My return lines were past their best and a couple of them were leaking fuel down the injector. The evil little hole you're referring to was bubbling on mine as well but only on the ones where the fuel was leaking. New lines, no leaks, no bubbles. :D

hog... which hole was bubbling/where.. on yours ?

cheers.
 

roadhog

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The "small dark evil hole giving bubbling water by yellow arrow". :)
 
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chastrain

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The "small dark evil hole giving bubbling water by yellow arrow". :)

Haha hey ho :) Ok.. but i don't get it, why would new return lines stop what i think is an 'evil water leak' in the head, unless it isn't what i think it is, which means i've just lost that furrowed look. :)
 

roadhog

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Right, let me try again. :)
I had a leak on a couple of my injectors. I would have sworn it was coming out of the cylinder head, bubbling out of the little hole you identified with the yellow arrow. I couldn't see any leaks from the return lines but changed them as they were the cheapest part to start with. Hey presto, all fixed.
I have no idea why the holes were bubbling, OK, there was fluid sitting on top and obviously air coming out but I do not know why the air was coming out.
Just get yourself a length of hose (meterware, costs pennies) and see what happens. Don't forget the end one with the bung in it. :)
 

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Air comes out of the injector shaft because the seats at the bottom of the injectors are not 100% true, leaking compression!
 
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chastrain

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Right, let me try again. :)
I had a leak on a couple of my injectors. I would have sworn it was coming out of the cylinder head, bubbling out of the little hole you identified with the yellow arrow. I couldn't see any leaks from the return lines but changed them as they were the cheapest part to start with. Hey presto, all fixed.
I have no idea why the holes were bubbling, OK, there was fluid sitting on top and obviously air coming out but I do not know why the air was coming out.
Just get yourself a length of hose (meterware, costs pennies) and see what happens. Don't forget the end one with the bung in it. :)

Many thanks hog ;-)

Ok, can but try, as you say, it'll do no harm, though i dabbed around the hole with the engine running to catch and identify the leaking fluid and found it to be scentless thus my conclusion as to it being water.
You say holes ..so you had more than one 'air bubble leak' on more than one injector ?

I'll go for it, nice if we knew why it's happening though.

Cheers.
 

Alex Crow

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in this case it could be a leaking pre-combustion chamber. that is exactly where i would expect to see it leaing from. according what the o/p has said he has an injector leaking fuel mid length at the join, i suspect the liquid is diesel not water, but i feel the op could work this out for him/herself. if it were coolant we would expect antifreeze and calcium staining where it evaporates. i am sure it is just an injector fuel leak, and a pre-combustion chamber compression leak - quite common.
 

roadhog

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The bit the injector sits in!!:D:D

chamber if you wish sir!:eek:

Its still leaking compression up the side of the chamber/injector shaft!!
In that case I'll live with it. I did consider taking them out at the time but thought better of it as there seems to be some potential for a mishap.

You say holes ..so you had more than one 'air bubble leak' on more than one injector ?

I'll go for it, nice if we knew why it's happening though.

Cheers.
Two leaking injectors on mine, one hole per injector just like yours. S/U above has just explained why it's happening.
 
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chastrain

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Air comes out of the injector shaft because the seats at the bottom of the injectors are not 100% true, leaking compression!


Hi sam , leaking compression ...ooooohh, as of the picture of the hole it seems to be beside the shaft, but ok if it's as you say, what's the fix.

Many thanks.
 

turbopete

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and to add my 2p worth, those leak off pipes do look very wet, like theyre perished and leaking, so as a length of pipe for them only costs a few quid, id just replace the lot, then you can forget about them for another few years!
 

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Hi sam , leaking compression ...ooooohh, as of the picture of the hole it seems to be beside the shaft, but ok if it's as you say, what's the fix.

Many thanks.

There is a tool we use for re-cutting the face of the head and the face of the injector, new seals and of you go!
 

turbopete

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There is a tool we use for re-cutting the face of the head and the face of the injector, new seals and of you go!

and there i was thinking non cdi engines were safe from this kind of problem! :roll::roll:
 


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