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MillionMileSprinter
02-09-2017, 01:32 AM
A buddy brought over his '05 Sprinter complaining of a fuel leak today and when I found out it was coming from "some black tube under the engine" I figured he had a leaky return line. No big deal. So I pull the injector cover off and all the wells were full of diesel fuel. I start the engine up to see if the cracked line or plastic "T" fitting leak is obvious and white smoke starts pouring out of the #4 injector area. Weird. I unplugged #4 injector and the smoke continued, with the engine now running significantly rougher. I can't find any specific spot on the return line thats leaking, so I shut off the engine and dry out all the wells. I inspect the best I can for any cracks in the wells, but my borescope isn't too HD at close up and the inspection mirror and flashlight can't show me much, either.
I start the engine up again and sure enough, white smoke is really pouring from injector #4 area. I know what Black Death is. Repaired a fair number of them, and this is different than any Black Death ive ever seen. Black Death has always been a spitting and chuffing. This is just straight white smoke billowing out. It's so thick I cant tell exactly where it's coming from. A bad injector seal (aka Black Death)? Cracked injector well (seems unlikely since no OIL is coming out and removing the oil cap makes no difference in the quantity of white smoke)? A cracked injector (maybe, but why all the white smoke)?
Any ideas?
Again- raw fuel filling the injector wells, starting with #4 and white smoke pouring out of injector well #4...
Thanks in advance for the replies!
Oh, and the only TDC is a fuel rail pressure error that has been intermittent in this van for the last year or so. I don't think that's related, but I've been wrong before.

ECU
02-09-2017, 02:27 AM
Leakage around the injector. It is Black death. The white smoke is combustion blowing out of the injector seal.

MillionMileSprinter
02-09-2017, 02:36 AM
Leakage around the injector. It is Black death. The white smoke is combustion blowing out of the injector seal.

Ok, I can believe that. But where is all the raw fuel coming from...?
Like I said, I've seen and repaired a number of Black Death problems and never seen white smoke like this nor have I seen this much raw fuel. And neither one is spurting out like I've always seen. The fuel is just appearing and quickly filling the wells and the smoke is sort of billowing. And its not from the wiring, either.
I wonder if I don't have a cracked or at least faulty injector on my hand.
I'd love to hear your explanation, Dick. Show me how I'm wrong. :smilewink:
...and my buddy would be thrilled to hear he doesn't need a fork out the dough for a new injector... :bounce:

lindenengineering
02-09-2017, 03:52 AM
I suspect you have a cracked or parted injector.
What not remove it and re-connect it inverted and crank it over!
My rocket test!

Yes it will start with no injector and you will have the chuffs but the fuel will be blowing out all over the place of its broken..
Keep and hands away from HP injection spray patterns and use eye wear! Think safety when doing this stuff!
Dennis

ECU
02-09-2017, 03:53 AM
When I popped of the lid to look at mine, I had the gaseous fuel coming out as both smoke and small particles of fuel. Some is firing in the cylinder, some is not. The liquid is fuel condensed out of the fumes. The mechanic found three injectors leaking round the base.

PATECO
02-09-2017, 06:05 PM
This is what my #2 looked like after loosening the hold down bolt to pop it out for seal repair. Lots of white smoke.

10202505793203562

CLICK THE PICTURE TO PLAY VIDEO

I managed to fill my wells with diesel after the repair. High Pressure fuel supply line was not fully seated on the injector before I tightened. Maybe your hold down has given up, and the injector has moved/popped out enough to break the HP fuel line seal causing a leak?

MillionMileSprinter
02-12-2017, 01:10 AM
Ok, so after replacing injector #4 and seal and hold down bolt, the smoke is now coming from #3!!! WTF!!!
I pulled out injector #3 and replaced the injector seal, put injector back in and it still was smoking!
Anyone? Any ideas?
One more thing: with the DAD, I did a compression test and #2 came back as ZERO. Then did the injector shut off test and every injector shut off caused the same rough running. No change in smoke coming from #3. I do the smooth running test and all injectors are within one or two digits of each other. Then I do the DAD compression test and #2 is still coming back as ZERO..... My next step is to clean #3 injector seat and replace the seal again. Unless anyone has a better idea...
Thoughts?

lindenengineering
02-12-2017, 03:23 AM
This is what my #2 looked like after loosening the hold down bolt to pop it out for seal repair. Lots of white smoke.

10202505793203562

CLICK THE PICTURE TO PLAY VIDEO

I managed to fill my wells with diesel after the repair. High Pressure fuel supply line was not fully seated on the injector before I tightened. Maybe your hold down has given up, and the injector has moved/popped out enough to break the HP fuel line seal causing a leak?

That is a badly seated injector!
Dennis

autostaretx
02-12-2017, 06:28 PM
Dennis also mentioned the possibility of a cracked injector... pulling and reseating won't fix that. Replacing will.

(you could move #3 to a different cylinder and see if the smoke moves too... but that may damage the threads or the seat in the "new" cylinder, so i don't recommend it as a practice.)

--dick

MillionMileSprinter
02-12-2017, 11:03 PM
Finally figured it out. Injector #4 was indeed cracked and replacing it along with a quick resurfacing of the seat, a new seat seal and hold down bolt fixed it right quick. Now, #3.... Turns out the threaded fitting that is male on both ends with a 13mm nut in the middle was loose where it went into the injector (not on the end that the metal line from the rail threads on). Just enough to allow atomized fuel to escape where it would shortly either turn back into liquid and fill the well or create a smoke that would quickly shoot up, but NOT like the chuffing that accompanies leaking injector seals or loose injectors. In a still photo, they look very similar, but in real life, the two are quite different in sound and behavior.
He also had a leaky fuel return line and I bought the one with the metal fittings instead of the OEM MB plastic fittings. The lengths of hose between the fittings are a bit long, but the metal fittings are a good fit in the top of the injectors.
Thanks for all the help!

Aqua Puttana
02-12-2017, 11:27 PM
... Now, #3.... Turns out the threaded fitting that is male on both ends with a 13mm nut in the middle was loose where it went into the injector (not on the end that the metal line from the rail threads on). Just enough to allow atomized fuel to escape where it would shortly either turn back into liquid and fill the well or create a smoke that would quickly shoot up, but NOT like the chuffing that accompanies leaking injector seals or loose injectors. In a still photo, they look very similar, but in real life, the two are quite different in sound and behavior.
...
That is a good reminder to always use a backup wrench as recommended when loosening the injector fuel fittings. Without a backup wrench unintended joints can end up loose.

... I'm not saying that you don't use the proper procedure. This is just a general reminder.

Thanks for the follow-up and info. :thumbup:

vic