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#31
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I think rcouts has the simplest idea for a quick fix. A 15 thou steel shim could be cut from a piece of shim, no big deal, its of the shelf & a pair of good sharp scissors would cut it like paper. It would need to exactly fit on top of the liner. then just put a new gasket on.
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Grumpy Old Diesel Owners Club group I no longer question authority, I annoy authority. More effect, less effort.... ![]() 1967 230-6 auto parts car. rust bucket. 1980 300D now parts car 800k miles 1984 300D 500k miles ![]() 1987 250td 160k miles English import ![]() 2001 jeep turbo diesel 130k miles ![]() 1998 jeep tdi ~ followed me home. Needs a turbo. 1968 Ford F750 truck. 6-354 diesel conversion. Other toys ~J.D.,Cat & GM ~ mainly earth moving |
#32
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A 0.014" gap is about 0.3mm. That's a fairly thick chuck of metal to fall into the combustion chamber. In addition, any shim applied, especially the thicker it is, will not expand and contract with the cylinder wall, so 700-1000 psi of combustion will bust the "ring shim" apart, and much bigger pieces will fall into the chamber. The only practical non-replacement method seems to be to weld a similar material on and hone it. But, that needs the block to come out, in which case you can just replace the lining. Btw, this lining thing is really silly. Mercedes made the engines so that the liner is replaceable, but they didn't bother to put a lip at the bottom of the cylinder or a flange at the top of the liner to keep the liner in place. I've heard that some diesels have stops at the bottom, but this still allows the liner to drop an 1/8 inch or so. So, by the time you pull the block to replace the liner, you could for the same price just get a low-mileage used engine--which then comes with it's own unknowns! I have to say that this liner design is a design flaw. It doesn't happen as often as Land Rovers and Harley CVO's, but still a weak point in Mercedes engines, diesel or gas.
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#33
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Such a shim would be no more likely to end up in the cylinder than a piece of gasket. I know of motors that have shims like that for head gaskets. A steel shim will not burn away. The CI head will burn first. The same applies for expansion & contraction, the gasket is not falling to pieces in a motor.
It looks like people are jumping to blame design for what is very poor workmanship when the liner was fitted. I see the OP has not replied in a long time. I guess he just replaced the gasket & sold the car, thats probably what the last owner had done.
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Grumpy Old Diesel Owners Club group I no longer question authority, I annoy authority. More effect, less effort.... ![]() 1967 230-6 auto parts car. rust bucket. 1980 300D now parts car 800k miles 1984 300D 500k miles ![]() 1987 250td 160k miles English import ![]() 2001 jeep turbo diesel 130k miles ![]() 1998 jeep tdi ~ followed me home. Needs a turbo. 1968 Ford F750 truck. 6-354 diesel conversion. Other toys ~J.D.,Cat & GM ~ mainly earth moving |
#34
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I am not familliar with these engines nor have I had one apart but I am familliar with large diesels. Here is my $0.02 based on the engines I work on.
Large truck engines are commonly shimmed under the liners. If a liner protrudes too far, the counter bore is cut down. If the liner sits too low in the counter bore, it is shimmed back up into spec. If the liner rests in a counter bore, the liner could be shimmed. The shim would need to be placed under the lip of the liner. Pull the liner out, cut the shim and reinstall. Shim stock is readilly available at tool supply stores. Could the liner be pulled out with the engine still in the vehicle? Google "cylinder liner puller" and see if one of those would work for you. |
#35
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For a relatively "flat" shim, it will be exposed to combustion pressure because the gasket hole diameter is greater than the linder's ID. This thin shim will eventually clog with carbon, and will be wedged up and flake off. For a relatively thick "ring" shim, it will be a dissimilar material, and therefore expand at different rate and extent. The pressures of combustion will eventually break the ring, and it will fall into the cylinder. However, a MLS gasket is a composite that is malleable, and its exposed edge of the hole will absorb the pressures. It's a lot like a twig versus a un-cooked spaghetti noodle. The twig will bend, but the noodle will break. Quote:
I know that whunter has this (Remove/Install engine cylinder Sleeve/Liner, but actual success DIY stories? And then, there's the task of putting the liner in. At the factory, I believe the blocks are placed in a HOT oven, and very COLD liners are slipped in. A similar trick I suppose would be to torch the cylinder walls, and slip in a liner that's been bathing in dry ice. But, you've got one shot to do this on a $250 liner, and if it binds half way, oh boy. Has anyone seen a DIY success story on a Mercedes liner replacement?
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#36
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jsap,
Are you expressing a personal opinion or do you have formal qualifications in machine design (eg Professional Engineer)? Liners do not cost $250 each. It is common when rebuilding these motors to replace liners & not pistons as is the case with many dry liner motors. Pressing dry liners is a common practice in motor rebuilding. I have seen blocks without liners bored & dry liners installed. Your comments about gaskets, twigs & noodles lacks technical substance. I have a motor here that has operated for many thousands of hours with such a shim on top of a liner.
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Grumpy Old Diesel Owners Club group I no longer question authority, I annoy authority. More effect, less effort.... ![]() 1967 230-6 auto parts car. rust bucket. 1980 300D now parts car 800k miles 1984 300D 500k miles ![]() 1987 250td 160k miles English import ![]() 2001 jeep turbo diesel 130k miles ![]() 1998 jeep tdi ~ followed me home. Needs a turbo. 1968 Ford F750 truck. 6-354 diesel conversion. Other toys ~J.D.,Cat & GM ~ mainly earth moving |
#37
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Here's what I said: By the time you've found a machine shop who can replace your liner (btw, a Mercedes liner (OEM) will cost the consumer $250, unless you get aftermarket), remove the engine, take the heads off, etc., you can replace your engine with a low-mileage engine for less money. So, if you think that my comment that the liner design in the MB engines are a weak point is unwarranted, then good for you. I know for a fact that liners can be designed in a way that will not slip, over-heating, stuck pistons, or whatever. Btw, what's your qualification? Also, what are the dimensions of your shim? Can you provide pictures of it with the gasket on top, prior to head installation? Also, I want to hear jparker164's story.
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#38
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jsap,
I have an Engineering degree from Adelaide University ( have previously posted a copy of my degree on this forum), over 30 years experience as a Professional Engineer (not a trade certificate & trade experience), while working in the USA previously I was a registered Professional Engineer in the state of Texas. I gather from your comments that you do not have formal Professional Engineering qualifications & perform an administrative roll. If you are in the diesel section of a machine shop as you say you are, it is highly unlikely that you would have "hundreds of PE's" working there, maybe a handful of fitters & turners. I notice interestingly that you dont actually say you are supervising "hundreds of PE's, instead just infer it. I dont work in a diesel shop, I have a consulting engineering biz (yes I employ a number of professional engineers) & also own a Civil engineering contract biz. Cant give you a pic of the shim as the motor is assembled. I am sure that others who have worked on motors from EM equipment will know what I am talking about. jparker64 appeared to have replaced the motor. Others on this forum have replaced liners in the past & commented about it. Only a fool would bother with an OEM liner ~ a fool & his money are soon parted!! Now what is this qualification that you have? I wait for an answer in anticipation!!
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Grumpy Old Diesel Owners Club group I no longer question authority, I annoy authority. More effect, less effort.... ![]() 1967 230-6 auto parts car. rust bucket. 1980 300D now parts car 800k miles 1984 300D 500k miles ![]() 1987 250td 160k miles English import ![]() 2001 jeep turbo diesel 130k miles ![]() 1998 jeep tdi ~ followed me home. Needs a turbo. 1968 Ford F750 truck. 6-354 diesel conversion. Other toys ~J.D.,Cat & GM ~ mainly earth moving |
#39
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Enough pissing. I can see you're the prickly type. Save your time and give me the material used, the dimensions of the shim (thickness, ID delta from linder ID and gasket opening), so you can teach me under what conditions your shim supposedly survived. Enough about your fool business. Your diesel is not alu-sil, my money is mine, and if you bought a Mercedes, you've thrown enough money away. Provide links to DIY methods and results. If you're not going to be generous, then shut it. All I wanted to know was how jparker fared. Of course, it's cheaper to replace the block then to install a liner. Can you still do the math?
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#40
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question: what if you were to stack two cylinder head gaskets on top of each other? you know, how some guys put spacers of different thicknesses under carburetors...
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#41
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woah, woah, woah. i see i've just stepped into a MAJOR battle without even reading through the whole thread.
guys...advice: take three steps BACK from this thread. fists WILL fly. Chuck Norris WILL be involved.
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i know Jim Smith. i don't actually know him, but I know of him
http://imageshack.com/a/img923/6201/RQ1H6A.jpg |
#42
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Every engine is different, depending on wet vs dry. But, the one problem with open decks is that surface area of the top of the cylinder to the head gasket sufficient to contain the combustion pressure, which can run as high as 1000 psi on naturally aspirated engines, is not very much. With a slipped liner, the surface area becomes half on an open deck design. In actually, though, because the preformed MLS head gasket opening is the same for the various group sizes of the cylinders for even the same engine, and the actual area of the contact can be 1 mm less in web width than the potential 6mm (cylinder wall + liner thickness), so the surface area might be about 70% of the original. Instead of a 5mm width, you'll have about 3.5mm. Doubling up on the MLS gasket doesn't really help contain the pressure. The pressure loss is perpendicular to the cylinder axis, from within the cylinder to the adjacent coolant. Adding more gasket thickness under the head simply allows more cushiness for the pressure to escape. Rather, reducing the thickness would be better, but MLS gaskets are thick for the reasons that it much provide vibration resistance, water jacket, heat cycles of the various metal parts, and so on. The other things about adding another MLS gasket is that it increases the volume of the chamber (changing the compression ratio), the spark plug electrode position, and misalignment of the intake manifold (if you have a V configuration). Also, it's difficult to know how much to turn the Torque Tighten to Turn (TTT) bolts. Long story short, the gasket depth cannot really be changed on some engines.
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#43
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May I quietly and politely ask what the cost of replacing 5 dry liners on a OM617 would cost in a machine shop where you are?
I gather the OEM liners would be $1250 with out fitting. Is that correct? I only ask as it may be a choice I may need to make in the future.
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1992 W201 190E 1.8 171,000 km - Daily driver 1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone 1965 Land Rover Series 2a Station Wagon CIS recovery therapy! 1961 Volvo PV544 Bare metal rat rod-ish thing I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior ![]() Don't leave that there - I'll take it to bits! |
#44
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I do know, however, that many machinists have done liner replacements on Mercedes diesels. The cost starts with labor: pulling the engine. Once you've pulled it, then some machinists will not warranty the work unless they inspect the entire engine and approve the condition as well perform the work they recommend. So you'll start wracking up costs for parts and labor for the block and heads. In the end, it's often cheaper to replace the entire engine. The wrecking yard or dismantler will often trade your broken engine for a low-mileage used one for about $1000 to $2000. They'll often give you compression numbers on the cylinders as proof that the engine is alright, but it's really a gamble. My recommendation is to interview as many machinists as possible. Eventually, you'll find a couple of tiers of costs. And look into used engines, as well. Weigh the costs and risks, and go from there. Either way, you'll probably have to remove the engine, so there's really little difference in that respect. The OEM liners for your OM617 might be cheaper. Mine is pricey because it's silicone crystal aluminum, but you can get aftermarket for them too. You could try aftermarket for yours from reading other people's comments and feedback. For diesel, from talking to machinists and mechanics around here, they've done dozens of them, already have tools for them, etc.... But for gas, they seem to scratch their heads, and I only got a number of a guy who someone knew ten years ago who used to do gassers near the Mexico border. Admittedly, I haven't called everyone in town, but if you're serious about it, then a few phone calls start to give you an idea pretty quickly. Good luck.
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#45
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The sleeves on a 616 cost 42.99 each from fastlane. I have pressed them out personally in my favorite machinist's shop. It does not take long if you have a 20 ton press. It takes a lot of pressure to get them out, I always wonder if the sleeve is going to come out or the block explode, but the sleeves always come out. Of course the real work is assembling and disassembling the motor. If I had them do it for me I suspect they would charge me about 30 or 40 per cylinder labor, not including disassembling and reassembling the motor.
Sleeving a gas motor is no big whup either, you have to overbore it and leave a lip at the bottom, then install an appropriate diameter sleeve and hone to fit your piston. I imagine they would charge 100 to 150 per cylinder if you took the bare block in with a piston to hone to. Prior to installing the new sleeves he puts them in the fridge for a while, I believe. ![]()
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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual. ![]() ..I also have a 427 Cobra replica with an aluminum chassis. |
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