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tolsen

Egr Cartridge Removal

61 posts in this topic

Removing the whole EGR valve from the 450 Cdi is a very complex and time-consuming procedure, which is strictly not required.

You can remove and clean EGR valve in situ by removing actuator and steel valve cartridge from aluminium housing. Removing cartridge is made easier if you have in your possession a suitable tool that can turn cartridge and break it free from soot and hard deposit inside housing.

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Removed cartridge after cleaning using elbow grease and Mr Muscle Oven Cleaner. T25 Torx bit, 1/4" ratchet with short extension and special home made tool used to rotate and break free cartridge in housing. I have later been advised the bolts actually have 4 mm Allen heads. T25 Torx bit is therefore not the right for these small bolts and will damage the heads and make it difficult to fit the right 4 mm Allen bits.

The area where the tool fits measures 28.09 mm in diameter. The slot is 5.85 mm wide. ID of tool 28.25 mm and width of tooth 5.6 mm. Tool is also guided in aluminium housing. You have to keep twisting cartridge until it moves freely and can be pulled out with pliers. I have drilled 6.5 mm radial holes in my tool so I can turn tool using a screwdriver.

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Exhaust inlet into valve cartridge.

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Exhaust outlet from valve cartridge. Exhaust flows out of the slot in above photo and out of its tip, see photo below.

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Close up view of seat and disc. Note that seat is serrated and burnt. It may be possible to repair by machining but cartridge can’t be easily disassembled since valve at end is TIG welded to valve stem. This valve won't seal but no major problem since I've blanked off exhaust supply at exhaust manifold.

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View from engine space and EGR valve aluminium housing with actuator and internals removed. Valve cartridge fits with slot facing the lower bolt hole (the most inaccessible bolt).

Blanking off exhaust supply to EGR valve will ensure there is no need to open out and clean in the future.

Tool is made from a brass pipe fitting. Its tooth is stainless steel and silver brazed to slot filed in pipe fitting. Tool is turned down to 39.3 mm on the OD where it is guided in aluminium housing.

One can chamfer the cartridge as shown in below photo but diametrically opposite slot (12 o'clock, 6 o'clock is position of slot). Initially I chamfered 60 degrees anti clockwise from slot when viewed from actuator side but found that was no good due to my chisel interfering with car body.

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A sharp chisel can now be wedged into the chamfer to pry cartridge out making next time EGR clean a whole lot easier and no need for any special tools that are unavailable unless you make your own.

Those lucky to have access to a metalworking lathe can chamfer the whole circumference but leave at least 0.5 mm of land.

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Brilliant! Nice work as usual, I've added a link (with credit) to the clean the valve wiki.Thank you, Tolsen.

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I just tried this, on my spare EGR. The slot or chamfer can be cut in place with a (gasp) hacksaw, two of them in line with the two solenoid mounting bosses that you can reach. Some way of applying torque to get some rotation to break loose the carbon deposits will still be required before you have any hope of removing the sleeve, along with a liberal soak in an appropriate cleaner. My spare valve was in a vise, of course, so trivially easy to rotate. Mounted in the car another story, of course. A tool like Tolsens will be required. I shall be making one, may make it available to all members on a floating pay the postage, use it and hold it until the next member requests it. I have a lathe, so it will be easy. If this comes to be it will be listed on the "clean the valve in situ" wiki, with the current custodian named.Again, thank you Tolsen, this has been in the back of my mind to investigate. The actual valve is the most important bit to clean, and can't be done properly in place. Full removal of the entire valve is far too involved to be an optimum solution.

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Really just a slide in unit. The solenoid retains it for the first 10 kilometers, then the carbon takes over the job. On an older valve it will be a royal pain to get it broken loose from the carbon. A brand new or freshly cleaned one will just drop out.

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I mentioned I did this by accident when cleaning my EGR and after that it is how I cleaned my EGR from then on until I removed it. In my case the first time I was wiggling around with a screwdriver getting as much junk as possible out, and the cartridge popped partway out, I wound up using vice grips with the jaws taped up to prevent scratching to twist it slightly and remove it. This is how I removed it after that, the twisting broke it loose from the carbon and then the cartridge could be removed easily. I am sure Tolsen's solution is more elegant and correct, but if you need to my way works as well. Make sure you get the cartridge back in the correct orientation though as it does seem to cause problems if it is off ( or there was just something else I jostled when I had problems with mine the first time, and after reorienting it jiggled back into place )

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I made the tool out of a 28 mm brass compression nut. Unsure whether those are available in Canada. These are very cheap in the UK costing less than GBP 2 each, obviously price varying a bit depending on where they are sourced.

DSC03189.JPG

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I've had a few hellish days with work, no time yet to do anything. I will do up a tool. Already designed it and found the materials.Even the esteemed Tolsen will be forced to admit it is a nice design, and totally free. A lathe is required, which I have.

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As I said your way is better, but in a pinch ( or the first time someone pulls it out) my way does work. If I were still doing it I would go with something similar to your solution now that I see it, as I said yours is more elegant and correct, and makes it look like it should be that way, as always very impressive work on your part.

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Tool is made! Pics to follow. A thing of beauty it is, and functional to boot.Is anyone in the Vancouver area having EGR troubles and wants to be the guinea pig? Mine is recently cleaned out and working perfectly, so I'm not sure I want to mess with it yet.

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Posted (edited) · Report post

Tool:post-5138-1336247777_thumb.jpg post-5138-1336247740_thumb.jpgMaterials: Stub of 1" shaft, already with 1/4" keyslot, center drilled and tapped to 1/2" NC.Hub from worn out chain sprocket, sprocket cut off, OD machined to loose fit inside aluminum EGR housing, ID to snug slip fit over flange of valve insert.Retaining ring just a disc from worn out electric brake, machined to fit land on hub.1/4" key-stock, end hand filed to fit slot in cartridge.1/2" NC bolt and nut to apply torque with.Advantages: Tight well-aligned fit due to being guided by both EGR housing and most crucially the flange of the cartridge.Key is held well by both the shaft and hub, rigid to within a whisker of the cartridge. Tool is retained by ring held on by screws into solenoid mount holes. You can concentrate on applying smooth torque, without danger of tool coming out of the rather shallow slot.

Edited by Alex

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Looks very good but you have no brass you can polish up to a brilliant shine.

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You are right! I could get that pinky/purpley anodizing on the aluminum, I suppose.

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So, this is available for borrowing should the need arise?

Yes. I still need to do a valve in situ, possibly mine (maybe yours?), take photos and write up instructions. It took me less than an hour and no cash to whip that one out, I won't need it more than one every few years and can easily whip up another if needed.

I think that once it is tested and recorded, it will go out into the wide world to make new friends, help clean one valve at a time then be mailed on to the next user. Just keep track of the location on the wiki page, it can just stay with the last user until requested elsewhere.

Prepaid postage is so much simpler than collect, so a user will receive it free with a heavy moral obligation to promptly mail it on when requested. (Karma will getcha bad if you shirk this!) Rush service the responsibility of the recipient, regular parcel post is all you should pay for.

I quite like the design now that it is done, if anything will turn a stubborn valve this will. I see no improvement possible other than shiny brass or purple anodizing.

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From what I've been able to ascertain, our EGR is fine.Maybe because of the use of Biodiesel since almost new?Anyway, glad to know it available...

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+1, so far so good with 175,000 km on the second EGR.But if I need it one day, I will be happy to partake, thanks!

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Looks very good but you have no brass you can polish up to a brilliant shine.

:D

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Excellent, Alex!

The Japanese kitchen knife collectors regularly do pass-arounds -- around the world -- of knives costing in the several hundreds (to several thousands) of dollars, and it works really well when someone is designated as the umpire charged with keeping track of locations. Usually a time limit is given for each participant. Because of the global nature of those pass-arounds, the participants are decided in advance and an itinerary is drawn up with the intent of minimizing shipping costs; for a purely-Canadian itinerary that is unnecessary.

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I need to clean the EGR in my daughter's car. I would love to have a shot. If you ever put this "on the road", I'm in.

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Posted (edited) · Report post

I tested the tool, it works like a charm, my EGR is squeaky clean again, the wiki is updated and the tool is ready to embark on a Canadian tour.

Edited by Alex

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I tested the tool, it works like a charm, my EGR is squeaky clean again, the wiki is updated and the tool is ready to embark on a Canadian tour.

I've just skimmed through those comprehensive instructions. One gets a bit overwhelmed by the amount of narrative. Suggest a 1, 2, 3 step by step recipe. I also see you use an Allen key. Mine is held on with 3 off female Torx headed bolts requiring a T25 bit.Most fiddly job is removing the lower Torx bolt. It is therefore essential that the tools used are the proper length. My setup with 1/4" ratchet, short extension, 1/4" socket and T25 bit worked perfectly. Too long and there is interference with ECU and cable harness, too short and you can't turn bolt without touching EGR socket. Total length of short extension with socket and bit fitted is 85 mm.

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Posted (edited) · Report post

Ours do have Allen bolts. At least my 2006 does, it might be a model year change or the Canadian cars were changed. No idea, but they are Allen, not Torx. Plenty of Torx elsewhere on the cars.As for the comprehensiveness of instructions... Well, for you I'd just say "Clean the EGR. You'll have to find some way to turn the insert, it seizes with carbon."The EGR is a source of much grief with our climate and crappy fuel standards. Most diesel here is only 40 cetane. It can easily be $1000 from Mercedes to install a new one, which is their only solution. It is really a straightforward job, albeit messy to clean one, but there are some tricky bits. I suspect theses instructions will be used by people who don't already know the smart inside out like you do, so better too much info than not enough.Anyway, tis done and I'm not redoing it, so it stands.

Edited by Alex

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It's easy to offer critiques from the outside but I think Alex has done a great job, not only in designing a spectacular tool but in offering to share it with the members. Thanks!

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