HappyFamilyVan
Captain Ahab
Thanks for the replies.
Noblemercedes warning: Change Turbo Inlet Seal every time disturbed
- Thread starter 220629
- Start date
apologies for further moving away from the main topic, but I am trying to see if I can replace the fuel filter without disturbing the turbo inlet seal.
the input turbo hose is at the top of this photo, and the mounting screw is just visible between the hose and fuel filter.
Got this far into it, and think I need to buy more tools. a flex drive and or ball end 5mm hex bit might let me loosen up the radial mounting without taking the hose off.
any suggestions?
I just experienced a loose 'orange' seal on my 2008, NCV3. It makes a distinctive low frequency (WOOO) sound, like a small exhaust leak, mainly when accelerating. There is a subtle loss of turbo boost and acceleration but does not go into LHM. Then ECL P0101 pops up, one of the Mass Air Flow faults. Open hood and wiggle the inlet tube... problem diagnosed.
Reading up on all the dire reports of turbo's ingesting the seal and self destructing I feel lucky, but sceptical that you need to replace the gasket unless it is damaged, degraded or the wrong type. I have simply reconnected the inlet tube dozens of times when doing standard maintenance, fuel filter replacement, glow-plug replacement, etc. over the last 8 years with no problems.
Amusingly I was dropping the vehicle off for air bag replacement under warranty at my local Dodge dealer, and they missed it, although they did recommend flushing the power steering and brakes for a princely sum, but that's another story.
Reading up on all the dire reports of turbo's ingesting the seal and self destructing I feel lucky, but sceptical that you need to replace the gasket unless it is damaged, degraded or the wrong type. I have simply reconnected the inlet tube dozens of times when doing standard maintenance, fuel filter replacement, glow-plug replacement, etc. over the last 8 years with no problems.
Amusingly I was dropping the vehicle off for air bag replacement under warranty at my local Dodge dealer, and they missed it, although they did recommend flushing the power steering and brakes for a princely sum, but that's another story.
on my 2015, I ended up pulling the hose between the turbo and air filter. no realistic way to get this fuel filter out without doing so.
apologies for further moving away from the main topic, but I am trying to see if I can replace the fuel filter without disturbing the turbo inlet seal.
the input turbo hose is at the top of this photo, and the mounting screw is just visible between the hose and fuel filter.
Got this far into it, and think I need to buy more tools. a flex drive and or ball end 5mm hex bit might let me loosen up the radial mounting without taking the hose off.
any suggestions?
I ordered a replacement seal, but decided, after close inspection, that the seal looked to be in good shape. I gave the outside of the seal a wipe with a towel wetted with some of the dieselfuel from the old filter, and put it all together. (with 3NM torque on the screws that snug the clamps on that hose.)
I understand inspection and re-use DIY. It would seem that improper re-assembly is the biggest factor. Part replacement each time is the conservative approach.
I would suggest that having a new seal on hand would be worth the investment. Without a new seal on hand the temptation to re-use a questionable seal would be great. Given 8 years service perhaps install the new seal and keep the still good one as a spare.
vicThis is the procedure I use. Replacement every time the seal is disturbed seems more designed to protect against damage from commercial service work where the mechanic may not be very careful about inspecting the seal, so it's easier to just replace it every time even if not necessary (on your nickel of course.) Otherwise it's not necessary to replace a seal in perfect condition, but I would have an extra on hand so (as Vic pointed out) you're not temped to put a questionable one back in service.
And I would not take the 3 nm torque spec too literately, that is essentially code to an experienced mechanic saying 'not too tight dumbass!' The proper procedure is to tighten so that there is a positive seal but not so much that the gasket is damaged. This does require some experience/feel but that's just part of the skill set anyone should have before attempting mechanical work.
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seems the seal I left in place did not stay there.
the estimate is $6300 for new turbo, intercooler and oil change.
I probably made it worse by applying engine oil to the seal. (even though there is some oil inside the air pipe)
probably should have used the new seal, and made sure all mating surfaces were clean and dry, then torque to spec.
the estimate is $6300 for new turbo, intercooler and oil change.
I probably made it worse by applying engine oil to the seal. (even though there is some oil inside the air pipe)
probably should have used the new seal, and made sure all mating surfaces were clean and dry, then torque to spec.
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Bummer.
Maybe diesel fuel wasn't a good choice.
I think you may be on to something with "clean and dry". Even if there is oil within the hoses/system, when the seal remains tight the oil never makes it to the seal faces.
Sorry. I'm not trying to pile on. My intention is discussion for others who might be in the same situation as you were.
It sure seems like a poor design as compared to what was used on the T1N.
Any chance the turbo can be rebuilt by Garrett?
vic
I have a request for quote from an independent shop.
unless it is way cheaper, I likely will let the dealer do the work. He did say he should be able to knock some off what the bill comes to. and the towing was free for me.
with under 30k on the rest of the van, I probably will go with a new turbo in any case IDparts has them for around $1300.\
indy estimate $4500. but by the time they came up with this, the dealer had the parts almost all installed
kind of an expensive lesson, but that is the way life goes sometimes.
my brother did a brake job on his chevy and spent $20k on back surgery as a result.
I now have greater apreciation for the original post. linked service note clearly says replace every time, 3 NM torque.
wondering what would be good to clean the mating surfaces with on the turbo inlet and inside of the tube.
suggestions on this welcome.
unless it is way cheaper, I likely will let the dealer do the work. He did say he should be able to knock some off what the bill comes to. and the towing was free for me.
with under 30k on the rest of the van, I probably will go with a new turbo in any case IDparts has them for around $1300.\
indy estimate $4500. but by the time they came up with this, the dealer had the parts almost all installed
kind of an expensive lesson, but that is the way life goes sometimes.
my brother did a brake job on his chevy and spent $20k on back surgery as a result.
I now have greater apreciation for the original post. linked service note clearly says replace every time, 3 NM torque.
wondering what would be good to clean the mating surfaces with on the turbo inlet and inside of the tube.
suggestions on this welcome.
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Carburetor cleaner doesn't leave any residue. I wouldn't spray it on. Dampen a rag and give it a wipe. Based only upon your experience, whatever is used to clean the area should not leave a residue and should be allowed to completely dry before installing the seal.
Such a sh*t design. It's amazing that they haven't included some sort of frame or skeleton molded within the seal rubber to stop this very expensive failure from happening. Seems to me that it wouldn't take much support to keep it from being sucked in. It must begin collapsing in one small area and then the distortion avalanches in for a complete failure.
vic
I'm really confused about how this happens. When properly installed the seal is on the outside if the turbo intake, in between it and the plastic pipe. If the seal is in place and clamped properly I don't see how it is possible for it to migrate in such a way that it gets sucked into the intake. The only thing I can envision is two possible scenarios... one is that upon installation the gasket somehow gets shoved out of position and into the turbo intake, but this doesn't seem very easy to do. The other is that due to excessive tightening of the clamp the gasket gets cut in half, allowing the now-separated trailing portion (with the lip) to get sucked in. I think this is what happened with the early design because that had a thin portion that was easy to damage, but updated replacement that has been out for many years is much thicker and not really prone to this. All in all a mystery to me.
Maybe sometimes the problem is the clamp is not tight enough, rather than too tight. I wondered exactly how tight the specified 3 Nm torque really is, so I got a small torque wrench of the type used on bicycles, with a range of 2 to 10 Nm. It turns out that 3 Nm is quite a bit tighter than what I would normally do when tightening a hose clamp by hand. I also found that if the clamp on the turbo hose isn't real tight, that the hose can be worked loose fairly easily by moving the hose back and forth. This could happen when people change the fuel or air filter, or remove the air box for other reasons, and put too much sideways stress on the hose. Eventually the hose could come off, and then the turbo seal can be inhaled by the turbo.
My turbo hose did come off once. Fortunately, the seal was not inhaled, but clearly it could have been. It wasn't my fault - no one had touched it since I bought the van until the first service at a dealer, but apparently the MB tech did not install or tighten the hose well enough after changing the fuel filter. Now, it is part of my regular under-the-hood inspections to check that hose is completely on the turbo and nice and tight.
My turbo hose did come off once. Fortunately, the seal was not inhaled, but clearly it could have been. It wasn't my fault - no one had touched it since I bought the van until the first service at a dealer, but apparently the MB tech did not install or tighten the hose well enough after changing the fuel filter. Now, it is part of my regular under-the-hood inspections to check that hose is completely on the turbo and nice and tight.
TooMuchHair
Active member
Mike, first I want to say I am so sorry this happened to your van, next I want to thank you for your original comments about changing your fuel filter. I did my 2015 today and your posts were very helpful, especially the pics of the omega shaped clamp.
So here are a few things for the future, when I saw that your seal stuck on the turbo (remembered others saying the same thing) I ran my heat gun on the turbo inlet for a few minutes and even though it would not budge before it it now slid off easily and left the turbo neck completely clean and stayed in the plastic clean air hose.
I too considered re-using the seal, but decided to use the new one I had ordered thinking "why carry it around?"
The next time you take this apart and look at how the seal needs to be worked into place into the female plastic part you will be able to see that just pushing it back onto the seal while still stuck on the turbo probably did not fully engage the step on the OD of the seal.
I literally just came in and saw this, so thanks again and know that I am bummed for you.And a huge thanks to all that Noblemercedes adds to this (and other) groups!
Around boats and airplanes that sounds like something which would be safety wired.
As parrot Poly - Thread Finder and owning T1N's, I'm not at all familiar with the NCV3's. Is this hose assembly something that could be safety wired to assure that the hose never leaves the proper position?
After a quick scan back through the thread it occurred to me that there isn't one picture of the hose/seal assembly. If someone adds some decent pictures I can copy/move them to my original post.
vic
It doesn't seem like wiring it could easily be done, at least not by me.
Since I have become aware of the importance of making sure the seal and hose are correctly assembled on the turbo, and the clamp correctly torqued, I haven't found any tendency for it to come apart during normal use. But I check it regularly because the penalty for being wrong is so high. Not as bad as the penalty for not getting the o-rings right in the oil filter right, for example, but a similar "gotcha."
Also maybe worth mentioning again in this thread that there are two different seals, orange and black, and they are not interchangeable. The orange seal goes with an earlier version of the hose, and the black with a later version of the hose. Hose and seal have to match. Also, there is a different orange seal used in some of the passenger car versions of this engine. Looks similar, but didn't fit as tight in my hose. So you can't just go in and ask for an "orange turbo seal." Get the right stock numbers. Or else it's gotcha, gotcha, gotcha.
I will get some photos of the outside of the assembled joint. will probably be a while until I take this apart again.
Thanks for the nice words and kind thoughts.
(it does seem short sighted that the design is so touchy overall. the fact there had to be tech guidance published is an indication of the failings of the design and material selection)
Thanks for the nice words and kind thoughts.
(it does seem short sighted that the design is so touchy overall. the fact there had to be tech guidance published is an indication of the failings of the design and material selection)
Mike, how did you discover the seal had been sucked In?
I found my turbo had been chewed, only upon my curious inspection of the turbo intake while changing fuel filter for the first time. All other service done my MB dealer to date. Seal is black and still in place. Doesn't look compromised in any way.
I'm with others on this. If installed correctly, how on earth does that seal manage its way off the turbo inlet, and slip into the turbo, without the inlet pipe coming out of plac, and the now loose clamp flopping around?
I found my turbo had been chewed, only upon my curious inspection of the turbo intake while changing fuel filter for the first time. All other service done my MB dealer to date. Seal is black and still in place. Doesn't look compromised in any way.
I'm with others on this. If installed correctly, how on earth does that seal manage its way off the turbo inlet, and slip into the turbo, without the inlet pipe coming out of plac, and the now loose clamp flopping around?
I heard the turbo whine, it refused to accelerate, and after I found a place to park, and had it towed to the dealer, a phone call with bad news.
I gave it a look in between, and did not see anything obvious.
remember the other end of the turbo inlet tube is clamped to the air filter housing.
I did not go down and look/photo the damage. (have to work sometime, especially with a big bill to pay)