I think what I like the most about these videos is the editing and the fast forwarding. So many other channel hosts ramble on and on and feel we need to watch a bolt being removed for 20 minutes. This is the way is should be done. No music. No ego. Just good informative education. My many thanks.
This is like comfort viewing for me. I watch these at night when im ready for sleep. Sometimes i have to rewind several times until i watch the whole thing. Such purity, watching a guy dismantle an engine and finding the broken bits.
M112 and M113 which have the same SOHC , 3 valves , 2 spark plugs per cylinder design as this V12 are renowned as extremely reliable engines. Right up there with best ever made by MB.
I took a 4.3L M113 from 236k to 297k miles before I sold it (transmission failed)... and bought a 427k mile M112. I've had a couple ancillary issues due to mileage (and would have likely failed on any domestic car), but on the whole, they get me to work and back with no complaining.
@@sethsantiago304 Quite literally, just oil and transmission fluid changes at normal intervals. Total motor issues in 225K miles: - Water pump (took me 1.5 hour to replace) - One set of ignition coils (because I waited too long on the plugs, the extra gap voltage stresses them) - Idler pulley seized up causing the belt to slice the lower radiator hose... took a combined 2 hours and a 5 mile tow home. I saw this one coming... but I gambled. - Failed oil cooler hose... the only really annoying fix as the hoses are very expensive and not available aftermarket. I simply replaced them with Mishimoto braided hoses and a new AN-style oil cooler that I custom mounted where the old suspension pump cooler was (see below). - If you count the transmission, I had to replace the wiring plug (twice). The o-ring fails and causes them to suck in air and the oil foams causing slippage. Super-simple 1/2 hour job... if you have a lift. That's it. It is a simple engine with gobs of juice. The hydraulic suspension is a different story, but I replaced that with coil-overs and had no more issues.
They are very reliable motor, as long as you keep basic maintenance and don't mess up with upgrade (They have some potential, but sometime people just doing it cheap)@@sethsantiago304
I had one of these in a CL600 - incredibly economical for it's size and enough power. I enjoyed the car a lot although it was from Mercedes' low quality period. I used to get 21-22mpg which I found incredible at the time.
I'm just now starting the video but these engines are VERY notorious for out-of-round cylinder walls and warping of the block, which causes all kinds of fun. So I'm betting that there may be more to this one than we can easily see.
And when the cylinder roundness are off tolerances the pistons are 'loose' in the cylinders and then the piston rings may start to spin. So that's why this engine may have suffered low compression. VW and Audi have had these same issues.
@@ville85 also issue with heat , stress and shit design the heads start to warp on their planed edges and won’t seal well loss of compression and sometimes undetermined because you can see unless gasket shows it which most of the time it doesn’t! This will cause the engine to overheat in areas but not necessarily will the gauge show this depends I had a caddy with the special sport trans and 325 hp northstar motor shit happened to me. Head bolts started to pull out from heat expansion over time pissed me off car was mint and really nice ride lotta balls it would chirp tires hitting 3rd in an auto trans with Trac on !
@@dan88rx7turbo22 What model was your car with the Northstar? As someone who has worked on practically every application of that engine, I am unaware of any 325hp version with a "special sport trans". Also, the head clamping failure mode was not as you describe. They fail due to lack of cooling system maintenance. The acidic coolant degrades the head gaskets, eventually reaching the head bolt holes. Over time, the head bolt threads in the block are compromised. Once they begin to fail, clamping force is reduced to the point that combustion gases start leaking into the cooling system.
I'm not a mechanic, but this thing looks like an engineering masterpiece with no intention of ever being repaired. I can't imagine how tight it must be in that engine bay to access stuff.
At the Benz dealership, I was going to have a bad week if I pulled up a R.O. for any V12! I would rather have a V8. There are many engineering faults on this engine. The predecessor for the M137 (that you are tearing down) was the M120 and the ME (motor electronics) is hard to grasp for most. It's crisscrossed. The left ME controls the right cylinder bank and the right ME controls the left bank. The oil cooler leaks in the valley of the engine; both cylinder heads have to be removed for removal/replacement. As for the M137 and same oil cooler. They introduced a completely new spark ignition system with ion measurement for fuel economy and cylinder shut-off (V12 to V6). Auto manufactures have tried. Even during factory training the instructors stated that the ignition rails have a 50% damage rate while trying to remove them with the engine installed. Toss them. As techs, we could just turn off they cylinder shut-down option if the owner wanted to. The Bi Turbo V12 adds even more issues with turbo coolant leaks. Step 1, remove or lower the engine to gain access to the turbo coolant pipes to replace the O-rings. You need a big wallet to repair these engines and vehicles as a whole.
since discovering this channel a couple off weeks ago, I've joyfully wasted hours watching in fascination. I've learnt a lot and thoroughly enjoyed doing so. Thank you!
While I have never experienced it myself, I have been told by many mechanics that an out of round cylinder bore will cause the rings to rotate and the end gaps line up.
Love watching your tear downs and the commentary. It amazes me how many engines die because of lack of simple maintenance!!! Regarding those lined up ring gaps, I remember watching an episode of Engine Power on PowernationTV and one of the builders mentioned how lined up ring gaps was an indication of the bore being out of round.
These parts will not be sold again. Think of it: the amount of cars with these engines on the road will only diminish in time. There will be virtually no demand for second hand parts. Especially vital engine parts.
The ring issue is the EXACT same issue Honda has/had with there Variable Cylinder Management engines. After about 80k miles, the ring gaps align like that and throw a code. The engine will then need to have the effected piston rings replaced. Happened to me and many others.
Don't four stroke piston rings naturally rotate as they run? Or do you mean that yes, they rotate, but at some point they align and will no longer naturally rotate?
I enjoy this content a lot being a car guy who's built engines. I really wish you'd add one thing to these tear downs. You mentioned several times that this engine is known to burn oil and have out of round cylinder bores. It would have been great had you measured the bores looking for out of round. It would have also been great if you popped out a compression ring from the pistons put them in the bore and measured how much wear was on the ring. Keep up the good work!
I remember when I was a kid been told that overheated piston rings when you bend them they stay bent and don't retain their original shape, does that still apply to nowadays rings technology cause Eric could've done that to confirm overheating.
Rings are known to have some gap to allow for expansion to prevent butting. Force air induction engines usually have more gap. The top ring is usually gap a bit more than the lower.
I'm a M112 fan so was good to see the insides of this M137 engine, still relatively simple compared to the latest Mercedes high tec engines. Keep it up I enjoy your vids.
Please tell me that was a typo.. I have yet to come across an m112 engine that didn't have screwed up timing... My God the sheer amount of plastic parts in the front of that engine! I have the m113, which is basically the same engine with two cylinders added, and I find it strange how I haven't had a single issue with it, I've owned my 2006 S430 for 6 years now, and in that time racked up 163,000 MI on top of the 90,000 that was on the car when I got it.. all I've done was replace the PCV gasket on the passenger side, new spark plugs, and just oil changes with mann fleece oil filters, and either Pennzoil synthetic 5W30 or mobile one 0w40.. it still runs perfectly at 253,000 miles!
Judging by the staining and scorching at top of skirts bottom of ring lands, this engine had a blow by issue. I don't know if it's indicative of all the engines or just that one, but would definitely be the oil burning culprit.
FWIW, I don't like the open deck architecture of most any of the kind. I suppose I was influenced by the old Vega engines who failed so quickly back in the '70s. Without a lot of R&D work and testing, I think a lot of insufficient designs made it to the market and they're troublesome.
@@aaronatwood9298 Oh, don't I know. Almost bought a Vega, used, back in the day but with the good fortune of choosing, bought a used Datsun 510 instead which turned out to be a keeper for well over 200k miles and then sold to a friend to live on.
The list of cars worse than the Vega or Pinto is pretty small, but thankfully, most of the "worse" were made from 1971-1983, and are either currently rust or been melted onto 3 Kia's
Onto the Mercedes, I bet those cylinders were very unstable while running going out of round dynamically. I'm a retired motorcycle mechanic, dedicated to the craft through the '70s and into the '80s. We had so much product improvement during the period that some auto makers were on a downfall. I owned SAABs during that time and the engine in my '99' didn't make it much over 100k miles before a piston apparently broke and I sold it as a fixer-upper - Triumph made engine.
Hey, I've seen some of your videos in the past few days. Love that Zephyr engine. First one I've ever seen. Man, love to have one and put in a street rod!
Well it looks like quite a well made engine! Definitely comes from a car where a significant chunk of the price actually is the power plant. If not for the cylinder deactivation and whatever causes the smoking issue, looks like it would be quite a reliable beast. Very cool teardown!
Leave an engine that long and that heavy on an engine stand w/o support in the front and yea, the bore will be oval in a short time....hours. Engines(at lease ones that you want to use should NEVER be left on an engine stand even for a day or two w/o being supported on both ends. Hanging one from the bell housing even for a short time w/o blocking it up in the front wrecks the thing. Chrysler school(Motech) that I went to in the '80s had a bunch of 2.2s on engine stands and the bores were visibly oval. Pretty educating for sure. I've seen friends so proud of their SB Chevy builds that never work worth a damn cuz the left the stupid thing hanging on a stand for months. No engine is designed to be hung from it's bell housing.
I don't sit around watching you tube videos, but your presentations, are the best. Snowman Ray has everyone snowed, the trans guy is good, but rough around the edges. And Scotty is, well Scotty. I love how you follow proper bolt loosening procedures even on stuff that's going in the scrap pile. You should go to Gollywood before you become too old. I would love to have that engine in a Hudson truck rat rod with 12 Stromberg 97's and zoomie headers!
The bores look like some variant of Alusil. I want to say Alusil tends to gouge/scour/shred rather than wear, so maybe the block structure itself is dimensionally unstable to cause bores to go out of round. In my experience with the Porsche 944 engine that was Alusil, the piston rings are the only significant wear item if the ferrous coating on the piston skirts remains viable and the engine wasn’t abused with deferred maintenance. The bores seemed pretty hard wearing. Supposedly they have to coat the pistons with some sort of ferrous coating with aluminum bores or the aluminum-aluminum contact with the pistons will start galling and destroy itself pretty quickly.
yes they are alusil. I'm not really a big fan of this technology but seems mercedes did have a better quality control than other (for example BMW). But still, it's kinda hit or miss, two exact same engine might have different lifespan, but mercedes did a better job to keep the variance low.
Today i learnt something that had been a little worry to me, my w212 E class has a worn cam lobe, no difference to the wear you indicated, so no more worries, engines done 130k diesel. Cheshire UK many thanks.
Wow, that's some intricate castings. And that valley cover was really over-the-top. I was impressed with the general cleanliness of this particular engine. However, the rods, appeared to me to be too thin and too long for any kind of high rpm/performance use.
I'd like to see you write a book on common engine issues and give your opinion on the best ones to own. While it's true that the info could be a bit late for new car buyers, I rarely buy new cars for myself. You could prevent history from repeating itself!
The only significant changes made to this engine when it became the m275 was that Mercedes beefed up the webbing in the block and head so that it could handle the stress of its owner power. The lack of structural integrity is what caused the out of roundness occurring.
Great job on this one. Great job on all your teardowns.... Not gonna lie, I've seen stuff that looked a lot worse than that, that was running fine before we took it apart..... A commenter before me said this, and I agree with it, that could have had some blow-by, no question. One hypothetical is, customer brings it in, it's blowing a little smoke, smells oily, water pump is noisy.... If you even bother putting a compression tester on it, you find a couple low cylinders, you just tell them it's done, it needs a new engine.... You're not gonna mess with this thing. Pull it out, sell it as a core....
That crank has the same layout as an I6 just oversized to fit a pair of rods per throw. The overall simplicity of the I6 and V12/flat12 makes them the best engines suited for anything that demands power and ease of maintenance. These layouts can be enlarged to any sizes without ruining any balance to the engine. Lightweight crank design and no balance shafts make them reliable power packs. On-road trucks prefer the I6 for compactness. The marine and power generation prefer the 12 for its very high output power.
He has the case of the drops! I had that last week when I was replacing a cylinder off of a Mooney Aircraft. The Lycoming IO-360 cylinder costs $1500.00 and I dropped it. Luckily no damaged but I had to get it pressure tested anyways
Actually looks like a well designed engine in terms of casting quality, beautiful in fact. And that double roll timing chain is no joke. High sulfur in US fuel is hard on Nikosil cylinder coatings.
I thought they got rid of Nikosil coating some years ago. BMW did due to their mid-nineties engines failing due to the coating wearing away and causing loss of compression. It got so bad the engines wouldn't start.
All piston rings rotate, it is random how gaps are aligned after tear down. The oil ring which in this case appears the Hastings style (now copied universally), rotates as a complete ring, the rails maintain their gaps relative to the installed expander gap. High ring rotational speed can induce wear, engine manufacturers have instrumented engines to measure this. A significant factor is the honing, unequal directional cut known to cause ring spinning. Mercedes and BMW build ultra clean engines, don’t know about Audi. This is why bores and bearings can look like new after high mileages. BMW Have great base engines spoiled by degrading front end coolant plastic.
hey maybe this will help someone out there and after seeing this can get some parts from you and get their Mercedes back on the road. It was kind of a shame to see this engine get torn down after seeing the condition of everything inside it looked really nice
To keep the coils from failing you have to gap the spark plugs properly to 0.8mm. Too large of a gap causes the spark to cross the coil instead of the gap damaging it. Mercedes doesn't even gap them properly from the factory. Just throws them in.
About the rings, they always turn or rotate as engine is running. The end gap placement doesn’t matter cause they turn soon as the engine starts rotating.
That was a really interesting tear down. The design of the coil packs is terrible, but as you said, it was pretty straight-forward to tear it down. I'm not a fan of open deck engines. I wouldn't be surprised if the root cause of that engine burning oil is the open deck block. There is too little rigidity in the block and it results in cylinder wear. Glad you got a lot good parts. Hopefully you do well on the engine. Thanks for sharing!
The UA-cam channel "Legit street cars" has just done one of those valley cover gaskets that you mentioned. He had to remove the entire engine from the car and it was a mammoth job. Heads had to come off and virtually strip down the entire motor, down to the short block.
Its not the cover gasket, its an o ring for a turbo oil line, that happens to be under the valley cover, that happens to have a bracket attached to it requiring removal of the heads which usually means the whole engine comes out.
That is ideal in terms of design. But if the quality is low, it won't matter. What I mean is not having the engine wound up tight. Build it to be wound up tight, then tune it down with less power.
I never took auto shop class. This channel helps me understand how engines are designed and what can go wrong. It's a long shot but any change of tearing down a Vanagon Waterboxer engine? I'm a 25 year Westy owner.
Just started this video. So one ig coil fails and you have to replace the whole damn bank! That's crazy. Truly a car for those who don't care about the cost of ownership. No wonder these cars depreciated like a piano falling out of a window. Who'd buy one secondhand? Oh, and that's five hundred bucks' worth of spark plugs right there, every service!
We used to find Lawn Boy 2 cycle mowers, strip them down and throw a few decks into a bonfire, wait a half hour then throw cinder blocks at them...WOOOOHOOOO!! Talk about a shower of sparks!!! Don't let it get on you though. Bird shot from a 12ga works too. I love me a Class D Magnesium fire...just don't get it on you. You can't put it out till it's done
It is nice to see you get an engine on good shape. This is the first time seeing a 12 cylinder marcades engine taken apart. Thank you for another awesome video. 😀👍🇨🇦
Back in the 80’s there was a batch of Buick 3.8 (maybe 4.1 too?) liter v-6’s that had oil burning problems, traced back to an assembler that had either on accident or purpose lined up the gaps on all the rings of every cylinder. The complaint was excessive oil consumption to the tune of about a quart per 1000 miles or so, which GM tried to initially say was acceptable. The dealer I was at did a ton of them, where we basically re-ringed the engines.
just so everyone is aware, the rings during normal operation rotate around the ringlands continously. You could assemble an engine mark the ring postion and turn it over just a couple of times by hand and find them already moved. The fact the rings were aligned is most likely just by chance.
@@Regular_Thomas It's a good thing they do rotate, otherwise you'd start scoring the cylinder bores where the gaps are. The ring ends would start chowing down...
Guys, I saw it with my own eyes. The engines came apart with the ring gaps lined up, on all the cylinders, every engine that had the oil burn problem. What you say is supposed to happen and what happens in real life are two different things.
Great Video - thanks! Yes, those Coil Packs are something else.... A bloody nightmare. I've heard them sell for upwards of $4000.00! Crazy money - and that's S/H! Ciao for now. :)
I swear we tore down a npi 4.6 with a bearing so spun we sheered the crank bolt off trying to turn it over. Every bearing looked beautiful and brand new. Was still very siezed till all the caps came off
Been subscribed for maybe 8 months when I discovered the channel. Totally random comment here, but you said you welcomed all responses. If you could good sir, zoom in with the camera, and amplify the microphone when your breaking loose head bolts. It is by far my favorite sound when working on engines. Tink!- Tink! - Tink!🔧
There's a little tiny o ring that goes bad in the valley of the engine on the oil cooler and the only way to fix it is to remove the entire engine from the car. Per Hoovie, it mechanically totals the car due to the labor cost to change it out.
MY WHOLE LIFE HAS BEEN DEVOTED TO MECHANICAL APPLICATION NO MATTER WHAT MY SPECIALTY SMALL BLK CHEVY UP TO THE END OF THE BUILD. I KNO NOTHING ABOUT LS BUT WHAT A INCREDIBLE MOTOR THEY R
I very much enjoy watching you tear down engines and analyze their strong/weak points. That said, it appears to me that Mercedes used about twice as many parts as they needed to.......I'm not sure what kind of power these make but when I compare this engine to a high-perf LS motor or one of Ford's Shelby motors, I have to ask myself........why all the complexity? It looks like putting in 3X as many parts as they needed to do the job. When you design an engine with less parts, the parts left out will never break, won't need to be stocked, will never cause you problems, etc. No thanks.
If you can get your hands on any Inline 5's (like the 2.5L VW had in a lot of stuff in the late 00's and early 10's) or older Volvo stuff, that would be cool.
Great job taking that engine apart buddy. Looked overall to be in decent shape. Hope you had a nice Thanksgiving. Be well. See you on the flip side. Big Al.
That water pump literally knocking around along with that low compression cylinder, was dead man walking for that motor. I think that locked up tensioner sealed its fate. These motors run so smooth even with a low hole its hard to tell unless you get an actual misfire. You basically have two six cylinders under the hood. The fact that the VCT was clogged didn't help either. That said I might interested in those coils. Lol.
Not many of us ever get a chance to work on or even see the insides of an engine like this one. I was very impressed and can see dollar signs$ on every part. Thank you. Have you taken apart a later VW tdi engine?
I remember when all cars had one single coil packs. LS coils seem to be put in everything these days. I had a alfa 156 come in with eml lamp on and misfire. the coil for that was $760+TAX & that was a 4cyl
Nice. You know, if you ever get your hands on some oddball engine, like a steam engine or a radial, it'd be really interesting to see those torn down, lol...
I think what I like the most about these videos is the editing and the fast forwarding. So many other channel hosts ramble on and on and feel we need to watch a bolt being removed for 20 minutes. This is the way is should be done. No music. No ego. Just good informative education. My many thanks.
Same here. I just get my popcorn and a beer, sit back and see what happens. No drama just the facts
plus the impact gun sounds like starwars blasters when sped up
That's why I don't make vids. I'm a professional at makin' short stories, LONG. 😆😂🤣
Plus additions to my vocabulary! :-)
That's the difference between someone doing these as a side project and having them as their prime income
Every time you do one of these I'm struck by how gorgeous some of the large castings are. They're so intricate an complex. Like pieces of art.
" intricate . And complex , like a piece of art",and might cost a Picasso to rebuild .😂LOL
MB engines in particular they seem way over built
This is like comfort viewing for me. I watch these at night when im ready for sleep. Sometimes i have to rewind several times until i watch the whole thing. Such purity, watching a guy dismantle an engine and finding the broken bits.
M112 and M113 which have the same SOHC , 3 valves , 2 spark plugs per cylinder design as this V12 are renowned as extremely reliable engines.
Right up there with best ever made by MB.
My daily driver is an M113K at 223,000 miles.
I took a 4.3L M113 from 236k to 297k miles before I sold it (transmission failed)... and bought a 427k mile M112. I've had a couple ancillary issues due to mileage (and would have likely failed on any domestic car), but on the whole, they get me to work and back with no complaining.
@@capn_shawn shitttt man, what maintenance procedures do you do to get it there?
@@sethsantiago304 Quite literally, just oil and transmission fluid changes at normal intervals.
Total motor issues in 225K miles:
- Water pump (took me 1.5 hour to replace)
- One set of ignition coils (because I waited too long on the plugs, the extra gap voltage stresses them)
- Idler pulley seized up causing the belt to slice the lower radiator hose... took a combined 2 hours and a 5 mile tow home. I saw this one coming... but I gambled.
- Failed oil cooler hose... the only really annoying fix as the hoses are very expensive and not available aftermarket. I simply replaced them with Mishimoto braided hoses and a new AN-style oil cooler that I custom mounted where the old suspension pump cooler was (see below).
- If you count the transmission, I had to replace the wiring plug (twice). The o-ring fails and causes them to suck in air and the oil foams causing slippage. Super-simple 1/2 hour job... if you have a lift.
That's it. It is a simple engine with gobs of juice. The hydraulic suspension is a different story, but I replaced that with coil-overs and had no more issues.
They are very reliable motor, as long as you keep basic maintenance and don't mess up with upgrade (They have some potential, but sometime people just doing it cheap)@@sethsantiago304
I can't tell you how much I enjoy my weekly visit to your channel and watching you do this. It's the greatest show on Earth!
That is a serious piece of enginering, I was a GM tech in the mid 80's and I have to say I've never touched anything like that.
Not really. This is incredibly simple especially for a German engine.
Yes, things like the detail and fineness in the castings, beautiful.
@@douglasm3310 the American version and German version of simple are two completely different things
These are my favorite videos every week. I appreciate the time and effort you put in to create this content, as well as the humor.
There's always been something soothing about the sound of head bolts cracking loose
I had one of these in a CL600 - incredibly economical for it's size and enough power. I enjoyed the car a lot although it was from Mercedes' low quality period. I used to get 21-22mpg which I found incredible at the time.
There is nothing more peaceful and calming than watching interesting engine disassembly at night and falling asleep after it.
I'm just now starting the video but these engines are VERY notorious for out-of-round cylinder walls and warping of the block, which causes all kinds of fun. So I'm betting that there may be more to this one than we can easily see.
And when the cylinder roundness are off tolerances the pistons are 'loose' in the cylinders and then the piston rings may start to spin. So that's why this engine may have suffered low compression. VW and Audi have had these same issues.
@@ville85 also issue with heat , stress and shit design the heads start to warp on their planed edges and won’t seal well loss of compression and sometimes undetermined because you can see unless gasket shows it which most of the time it doesn’t! This will cause the engine to overheat in areas but not necessarily will the gauge show this depends I had a caddy with the special sport trans and 325 hp northstar motor shit happened to me. Head bolts started to pull out from heat expansion over time pissed me off car was mint and really nice ride lotta balls it would chirp tires hitting 3rd in an auto trans with Trac on !
@@dan88rx7turbo22 I loved my 300 hp N.S. they need the head stud conversion done
@@dan88rx7turbo22
What model was your car with the Northstar? As someone who has worked on practically every application of that engine, I am unaware of any 325hp version with a "special sport trans".
Also, the head clamping failure mode was not as you describe. They fail due to lack of cooling system maintenance. The acidic coolant degrades the head gaskets, eventually reaching the head bolt holes. Over time, the head bolt threads in the block are compromised. Once they begin to fail, clamping force is reduced to the point that combustion gases start leaking into the cooling system.
Hey Eric , how about a straight Six Benz, you know the ones used on 90s 300s
I'm not a mechanic, but this thing looks like an engineering masterpiece with no intention of ever being repaired. I can't imagine how tight it must be in that engine bay to access stuff.
This one isn't as bad as some newer Benz designs
At the Benz dealership, I was going to have a bad week if I pulled up a R.O. for any V12! I would rather have a V8. There are many engineering faults on this engine. The predecessor for the M137 (that you are tearing down) was the M120 and the ME (motor electronics) is hard to grasp for most. It's crisscrossed. The left ME controls the right cylinder bank and the right ME controls the left bank. The oil cooler leaks in the valley of the engine; both cylinder heads have to be removed for removal/replacement. As for the M137 and same oil cooler. They introduced a completely new spark ignition system with ion measurement for fuel economy and cylinder shut-off (V12 to V6). Auto manufactures have tried. Even during factory training the instructors stated that the ignition rails have a 50% damage rate while trying to remove them with the engine installed. Toss them. As techs, we could just turn off they cylinder shut-down option if the owner wanted to. The Bi Turbo V12 adds even more issues with turbo coolant leaks. Step 1, remove or lower the engine to gain access to the turbo coolant pipes to replace the O-rings. You need a big wallet to repair these engines and vehicles as a whole.
since discovering this channel a couple off weeks ago, I've joyfully wasted hours watching in fascination. I've learnt a lot and thoroughly enjoyed doing so. Thank you!
While I have never experienced it myself, I have been told by many mechanics that an out of round cylinder bore will cause the rings to rotate and the end gaps line up.
Love watching your tear downs and the commentary. It amazes me how many engines die because of lack of simple maintenance!!! Regarding those lined up ring gaps, I remember watching an episode of Engine Power on PowernationTV and one of the builders mentioned how lined up ring gaps was an indication of the bore being out of round.
Ahh the soothing "pew pew pew" of the air drill. Love it.
Suggestion: Use a brass rod to avoid marring any surfaces of good parts (like pushing the pistons out). Risk avoidance never hurts.
Yeah, I was concerned for the crank throws too...
These parts will not be sold again. Think of it: the amount of cars with these engines on the road will only diminish in time. There will be virtually no demand for second hand parts. Especially vital engine parts.
The ring issue is the EXACT same issue Honda has/had with there Variable Cylinder Management engines. After about 80k miles, the ring gaps align like that and throw a code. The engine will then need to have the effected piston rings replaced. Happened to me and many others.
Yeah the dealership I work at has done many and still get them from people.
Don't four stroke piston rings naturally rotate as they run? Or do you mean that yes, they rotate, but at some point they align and will no longer naturally rotate?
I've torn down one of these exact engines from a 2001 CL600. The block isn't as "pretty" as an M120 in my opinion, but still a neat piece nonetheless!
One thing that shocks me is the complexity of all those castings... VERY intricate!
Yeah this thing doesn’t compare to the M120 is much prettier and engineered better in my opinion. Especially the closed block design.
M120 is one of the best engineered engines in the world
I enjoy this content a lot being a car guy who's built engines. I really wish you'd add one thing to these tear downs. You mentioned several times that this engine is known to burn oil and have out of round cylinder bores. It would have been great had you measured the bores looking for out of round. It would have also been great if you popped out a compression ring from the pistons put them in the bore and measured how much wear was on the ring.
Keep up the good work!
I remember when I was a kid been told that overheated piston rings when you bend them they stay bent and don't retain their original shape, does that still apply to nowadays rings technology cause Eric could've done that to confirm overheating.
Pretty much the same train of thought I had. With so little actual "carnage" I was wondering why all the oil burning.
@@oldtanker4860 Valve stem seals can make a car burn a lot of oil
@@alexstromberg7696 That’s where I would lay blame. The valve stems were soaked in oil.
Rings are known to have some gap to allow for expansion to prevent butting. Force air induction engines usually have more gap. The top ring is usually gap a bit more than the lower.
Thanksgiving weekend and we still get to see one go under the knife, a big 'en too, that's dedication to your fan base right there, thanks Matt.
Those bores are impressively clean.
How did you not laugh, chuckle or anything when you removed the waterpump, I'm over here gasping for air from laughing so hard
I'm a M112 fan so was good to see the insides of this M137 engine, still relatively simple compared to the latest Mercedes high tec engines. Keep it up I enjoy your vids.
Please tell me that was a typo.. I have yet to come across an m112 engine that didn't have screwed up timing... My God the sheer amount of plastic parts in the front of that engine! I have the m113, which is basically the same engine with two cylinders added, and I find it strange how I haven't had a single issue with it, I've owned my 2006 S430 for 6 years now, and in that time racked up 163,000 MI on top of the 90,000 that was on the car when I got it.. all I've done was replace the PCV gasket on the passenger side, new spark plugs, and just oil changes with mann fleece oil filters, and either Pennzoil synthetic 5W30 or mobile one 0w40.. it still runs perfectly at 253,000 miles!
Judging by the staining and scorching at top of skirts bottom of ring lands, this engine had a blow by issue. I don't know if it's indicative of all the engines or just that one, but would definitely be the oil burning culprit.
FWIW, I don't like the open deck architecture of most any of the kind. I suppose I was influenced by the old Vega engines who failed so quickly back in the '70s. Without a lot of R&D work and testing, I think a lot of insufficient designs made it to the market and they're troublesome.
@@whalesong999 The open deck was the least of the Vega issues. In many ways, it was worse than its Ford counterpart, the Pinto.
@@aaronatwood9298 Oh, don't I know. Almost bought a Vega, used, back in the day but with the good fortune of choosing, bought a used Datsun 510 instead which turned out to be a keeper for well over 200k miles and then sold to a friend to live on.
The list of cars worse than the Vega or Pinto is pretty small, but thankfully, most of the "worse" were made from 1971-1983, and are either currently rust or been melted onto 3 Kia's
Onto the Mercedes, I bet those cylinders were very unstable while running going out of round dynamically. I'm a retired motorcycle mechanic, dedicated to the craft through the '70s and into the '80s. We had so much product improvement during the period that some auto makers were on a downfall. I owned SAABs during that time and the engine in my '99' didn't make it much over 100k miles before a piston apparently broke and I sold it as a fixer-upper - Triumph made engine.
Way to keep the content coming! This is nothing like the zephyr flathead V12!! Love your teardowns, Eric. Greetings from Phoenix 🌵 USA
Hey, I've seen some of your videos in the past few days. Love that Zephyr engine. First one I've ever seen. Man, love to have one and put in a street rod!
Naah we need a flathead Ford V8. I am sure you see lots of them!!
@@henrys.6864 Thanks Henry!
@@ldnwholesale8552 Looks like the Ford 3V :lol:
Would be interesting to see the oil filter media on these teardowns - what kind of stuff ends up in the filter?
Well it looks like quite a well made engine! Definitely comes from a car where a significant chunk of the price actually is the power plant. If not for the cylinder deactivation and whatever causes the smoking issue, looks like it would be quite a reliable beast. Very cool teardown!
Until you realize the bores are coated and not sleeved
@@colchronic Ah that is a pain.
@@802Garagedarton makes sleeves for the V8. you could do the same for this if you felt like it
Looks like a piece of junk
@@colchronic Coated bores aren’t as bad as people make em out to be
Leave an engine that long and that heavy on an engine stand w/o support in the front and yea, the bore will be oval in a short time....hours. Engines(at lease ones that you want to use should NEVER be left on an engine stand even for a day or two w/o being supported on both ends. Hanging one from the bell housing even for a short time w/o blocking it up in the front wrecks the thing. Chrysler school(Motech) that I went to in the '80s had a bunch of 2.2s on engine stands and the bores were visibly oval. Pretty educating for sure. I've seen friends so proud of their SB Chevy builds that never work worth a damn cuz the left the stupid thing hanging on a stand for months. No engine is designed to be hung from it's bell housing.
I love building, fixing, buying, selling engines and transmissions!
I don't sit around watching you tube videos, but your presentations, are the best. Snowman Ray has everyone snowed, the trans guy is good, but rough around the edges. And Scotty is, well Scotty. I love how you follow proper bolt loosening procedures even on stuff that's going in the scrap pile. You should go to Gollywood before you become too old.
I would love to have that engine in a Hudson truck rat rod with 12 Stromberg 97's and zoomie headers!
The bores look like some variant of Alusil. I want to say Alusil tends to gouge/scour/shred rather than wear, so maybe the block structure itself is dimensionally unstable to cause bores to go out of round. In my experience with the Porsche 944 engine that was Alusil, the piston rings are the only significant wear item if the ferrous coating on the piston skirts remains viable and the engine wasn’t abused with deferred maintenance. The bores seemed pretty hard wearing. Supposedly they have to coat the pistons with some sort of ferrous coating with aluminum bores or the aluminum-aluminum contact with the pistons will start galling and destroy itself pretty quickly.
yes they are alusil. I'm not really a big fan of this technology but seems mercedes did have a better quality control than other (for example BMW). But still, it's kinda hit or miss, two exact same engine might have different lifespan, but mercedes did a better job to keep the variance low.
What I love most of these videos are the bolts breaking lose!!!! And that lil ass milwaukee putting in work!!!
My man, you're quickly becoming my favorite channel. Please, keep up the good work. :-)
In addicted to your tear downs and I’m learning
3/4 air ALWAYS does the trick !
Best part of Saturday is watching your teardowns!
I've always been impressed how tight head bolts can be threaded into an aluminum block.
Pretty cool disassembly. For a guy who really only rebuilds chevys ..... it’s cool to see how other manufacturers design their stuff.
Today i learnt something that had been a little worry to me, my w212 E class has a worn cam lobe, no difference to the wear you indicated, so no more worries, engines done 130k diesel. Cheshire UK many thanks.
Wow, that's some intricate castings. And that valley cover was really over-the-top. I was impressed with the general cleanliness of this particular engine. However, the rods, appeared to me to be too thin and too long for any kind of high rpm/performance use.
Not to worry. It's neither a high rpm engine nor does it make much horsepower. It's main attributes are smoothness, it's a V12 and it's expensive.
I'd like to see you write a book on common engine issues and give your opinion on the best ones to own. While it's true that the info could be a bit late for new car buyers, I rarely buy new cars for myself. You could prevent history from repeating itself!
The only significant changes made to this engine when it became the m275 was that Mercedes beefed up the webbing in the block and head so that it could handle the stress of its owner power. The lack of structural integrity is what caused the out of roundness occurring.
Answer I was looking for.
Great job on this one. Great job on all your teardowns....
Not gonna lie, I've seen stuff that looked a lot worse than that, that was running fine before we took it apart.....
A commenter before me said this, and I agree with it, that could have had some blow-by, no question. One hypothetical is, customer brings it in, it's blowing a little smoke, smells oily, water pump is noisy.... If you even bother putting a compression tester on it, you find a couple low cylinders, you just tell them it's done, it needs a new engine.... You're not gonna mess with this thing. Pull it out, sell it as a core....
That crank has the same layout as an I6 just oversized to fit a pair of rods per throw. The overall simplicity of the I6 and V12/flat12 makes them the best engines suited for anything that demands power and ease of maintenance. These layouts can be enlarged to any sizes without ruining any balance to the engine. Lightweight crank design and no balance shafts make them reliable power packs. On-road trucks prefer the I6 for compactness. The marine and power generation prefer the 12 for its very high output power.
“Rods per throw” hehe
You have to be capable of making really strong cranks and really stiff bottom ends though, otherwise the length of that crank will catch up to it
Maybe the most satisfying head bolt cracks yet!
He has the case of the drops! I had that last week when I was replacing a cylinder off of a Mooney Aircraft. The Lycoming IO-360 cylinder costs $1500.00 and I dropped it. Luckily no damaged but I had to get it pressure tested anyways
A Mercedes engine with an actual oil dipstick. That item alone outta fetch a pretty penny.
ditto for BMW
My M272 V6 has a dip stick.
Actually looks like a well designed engine in terms of casting quality, beautiful in fact. And that double roll timing chain is no joke. High sulfur in US fuel is hard on Nikosil cylinder coatings.
The engine with cylinder deactivation is a pure joke and the two yrs that engine lived if a used one rolls into the dealer they strip and crush it.
I thought they got rid of Nikosil coating some years ago. BMW did due to their mid-nineties engines failing due to the coating wearing away and causing loss of compression. It got so bad the engines wouldn't start.
All piston rings rotate, it is random how gaps are aligned after tear down. The oil ring which in this case appears the Hastings style (now copied universally), rotates as a complete ring, the rails maintain their gaps relative to the installed expander gap.
High ring rotational speed can induce wear, engine manufacturers have instrumented engines to measure this. A significant factor is the honing, unequal directional cut known to cause ring spinning.
Mercedes and BMW build ultra clean engines, don’t know about Audi. This is why bores and bearings can look like new after high mileages. BMW Have great base engines spoiled by degrading front end coolant plastic.
James, you are 100% correct about rings rotating. It constantly amazes me how many urban legends persist in the automotive repair industry!
hey maybe this will help someone out there and after seeing this can get some parts from you and get their Mercedes back on the road. It was kind of a shame to see this engine get torn down after seeing the condition of everything inside it looked really nice
Whew you got lucky on that right hand thread bolt.
Left hand. And yes, it's wise to double-check.
To keep the coils from failing you have to gap the spark plugs properly to 0.8mm. Too large of a gap causes the spark to cross the coil instead of the gap damaging it. Mercedes doesn't even gap them properly from the factory. Just throws them in.
Good to know. Thanks
Breaking head bolts is my favorite sound next to the *ploop* noise coil pack sleeves make.
Hans und Franz have out done themselves designing this one!
To confirm if the valve covers are magnesium, put a torch to it, if it burns up, it was magnesium....🔥
About the rings, they always turn or rotate as engine is running. The end gap placement doesn’t matter cause they turn soon as the engine starts rotating.
That was a really interesting tear down. The design of the coil packs is terrible, but as you said, it was pretty straight-forward to tear it down. I'm not a fan of open deck engines. I wouldn't be surprised if the root cause of that engine burning oil is the open deck block. There is too little rigidity in the block and it results in cylinder wear. Glad you got a lot good parts. Hopefully you do well on the engine. Thanks for sharing!
I've seen that a lot of engines that use cylinder deactivation have problems with oil consumption. It really creates more problems than it solves.
Cylinder deactivation does exactly what it was designed to. Which is to solve the issue of long lasting engines.
cylinder deactivation is hydraulic... the gunk in the actuators could made a nice V12 into a full time S6
and as always.... i enjoy watching you take stuff apart.
The UA-cam channel "Legit street cars" has just done one of those valley cover gaskets that you mentioned.
He had to remove the entire engine from the car and it was a mammoth job.
Heads had to come off and virtually strip down the entire motor, down to the short block.
Sounds fun
Its not the cover gasket, its an o ring for a turbo oil line, that happens to be under the valley cover, that happens to have a bracket attached to it requiring removal of the heads which usually means the whole engine comes out.
Was waiting for this, thank you for another great video!
Awesome video bro. Btw, if the piston ring gaps line up, that means the cylinder is out of round! Nice work
Could you explain how that process works?
That is ideal in terms of design. But if the quality is low, it won't matter. What I mean is not having the engine wound up tight. Build it to be wound up tight, then tune it down with less power.
I suspect a lot of that material in the solenoid screens was extras from the chain guides. It was pretty tidy inside other than those.
WOW, you get all the fun. I would love to have an engine like that just to take it apart.
Great video's. By the way has anyone mentioned you look like Adam Sandlers mechanical brother
I never took auto shop class. This channel helps me understand how engines are designed and what can go wrong. It's a long shot but any change of tearing down a Vanagon Waterboxer engine? I'm a 25 year Westy owner.
Just started this video. So one ig coil fails and you have to replace the whole damn bank! That's crazy. Truly a car for those who don't care about the cost of ownership. No wonder these cars depreciated like a piano falling out of a window. Who'd buy one secondhand? Oh, and that's five hundred bucks' worth of spark plugs right there, every service!
Eric weld some angle iron to the bottom of that stand to hold the drain pan in the middle
Great design, I am impressed.
We used to find Lawn Boy 2 cycle mowers, strip them down and throw a few decks into a bonfire, wait a half hour then throw cinder blocks at them...WOOOOHOOOO!! Talk about a shower of sparks!!! Don't let it get on you though. Bird shot from a 12ga works too. I love me a Class D Magnesium fire...just don't get it on you. You can't put it out till it's done
Nice to see something different like this
It is nice to see you get an engine on good shape. This is the first time seeing a 12 cylinder marcades engine taken apart. Thank you for another awesome video. 😀👍🇨🇦
Cool tare down as usual
I’m no car guy but I like watching you take these apart
Back in the 80’s there was a batch of Buick 3.8 (maybe 4.1 too?) liter v-6’s that had oil burning problems, traced back to an assembler that had either on accident or purpose lined up the gaps on all the rings of every cylinder. The complaint was excessive oil consumption to the tune of about a quart per 1000 miles or so, which GM tried to initially say was acceptable. The dealer I was at did a ton of them, where we basically re-ringed the engines.
The problems ONE person can create 😂
just so everyone is aware, the rings during normal operation rotate around the ringlands continously. You could assemble an engine mark the ring postion and turn it over just a couple of times by hand and find them already moved. The fact the rings were aligned is most likely just by chance.
@@Regular_Thomas It's a good thing they do rotate, otherwise you'd start scoring the cylinder bores where the gaps are. The ring ends would start chowing down...
Guys, I saw it with my own eyes. The engines came apart with the ring gaps lined up, on all the cylinders, every engine that had the oil burn problem. What you say is supposed to happen and what happens in real life are two different things.
@@GNX157 I hate to say it, but anecdote isn't the same as proof. Whatever your situation was, in the real world rings rotate.
Great Video - thanks!
Yes, those Coil Packs are something else.... A bloody nightmare. I've heard them sell for upwards of $4000.00! Crazy money - and that's S/H!
Ciao for now. :)
I swear we tore down a npi 4.6 with a bearing so spun we sheered the crank bolt off trying to turn it over. Every bearing looked beautiful and brand new. Was still very siezed till all the caps came off
I have this exact engine in one car. Awesome to see the inside out of it.
I just purchased one
Nice work done! Really enjoy your content 👍
Been subscribed for maybe 8 months when I discovered the channel. Totally random comment here, but you said you welcomed all responses.
If you could good sir, zoom in with the camera, and amplify the microphone when your breaking loose head bolts. It is by far my favorite sound when working on engines. Tink!- Tink! - Tink!🔧
I’ll consider it!
Definitely would make a cool coffee table.
That engine doesn't fail. Mine is solid except for a little lifter tick.
There's a little tiny o ring that goes bad in the valley of the engine on the oil cooler and the only way to fix it is to remove the entire engine from the car. Per Hoovie, it mechanically totals the car due to the labor cost to change it out.
Benz motors are a work of art. Certainly an engineering accomplishment.
Engineer: How many spark plugs do you want ?
Mercedes: YEEES!
MY WHOLE LIFE HAS BEEN DEVOTED TO MECHANICAL APPLICATION NO MATTER WHAT MY SPECIALTY SMALL BLK CHEVY UP TO THE END OF THE BUILD. I KNO NOTHING ABOUT LS BUT WHAT A INCREDIBLE MOTOR THEY R
I very much enjoy watching you tear down engines and analyze their strong/weak points. That said, it appears to me that Mercedes used about twice as many parts as they needed to.......I'm not sure what kind of power these make but when I compare this engine to a high-perf LS motor or one of Ford's Shelby motors, I have to ask myself........why all the complexity? It looks like putting in 3X as many parts as they needed to do the job. When you design an engine with less parts, the parts left out will never break, won't need to be stocked, will never cause you problems, etc. No thanks.
I don't see what you think is so complex about this engine, it's extremely simply built?
Id love to see a teardown on a 1.6 or 1.8 miata engine! Loving the videos!!!
If you can get your hands on any Inline 5's (like the 2.5L VW had in a lot of stuff in the late 00's and early 10's) or older Volvo stuff, that would be cool.
I actually have an early one to teardown out of a eurovan
Damn... seeing what i saw, i would have tried an engine flush and new water pump.. ahhaha
Great job taking that engine apart buddy. Looked overall to be in decent shape. Hope you had a nice Thanksgiving. Be well. See you on the flip side. Big Al.
Great video. Well-shot and well-explained!
That water pump literally knocking around along with that low compression cylinder, was dead man walking for that motor. I think that locked up tensioner sealed its fate. These motors run so smooth even with a low hole its hard to tell unless you get an actual misfire. You basically have two six cylinders under the hood. The fact that the VCT was clogged didn't help either. That said I might interested in those coils. Lol.
Not many of us ever get a chance to work on or even see the insides of an engine like this one. I was very impressed and can see dollar signs$ on every part. Thank you. Have you taken apart a later VW tdi engine?
I remember when all cars had one single coil packs. LS coils seem to be put in everything these days.
I had a alfa 156 come in with eml lamp on and misfire. the coil for that was $760+TAX & that was a 4cyl
I sent 1 to the scrap yard for exactly what you found. Plugged solinoids. Pretty common these days.
Nice.
You know, if you ever get your hands on some oddball engine, like a steam engine or a radial, it'd be really interesting to see those torn down, lol...
most skookum timing chain award goes to...