By on April 11, 2013

After finding a couple of Mercedes-Benz W123 coupes for this series, I decided to shoot the next four-door version of this legendary machine that I spotted. Here’s one in solid, stolid brown.
It’s pretty tough to beat the diesel W123 for sturdy construction and utter lack of corner-cutting in the build-quality department. These cars cost plenty, and their owners (usually) got their money’s worth. The price tag for a new 300D in 1978 was $20,911. That’s close to 75 grand in 2013 bucks, for a slow car that was reasonably luxurious but utterly bling-free.
This one made it to just 216,623 miles during its 35 years on the planet. Not bad, but a bit low for one of these cars.
Once it got a little battered and its interior was no longer so nice, this car’s days were numbered. Most likely, something broke that would cost more than a couple hundred bucks to fix, and the owner just gave up on the car.
Here it is, the legendary OM617 five-cylinder diesel. Not a lot of power, but ready for Armageddon!
Some junkyard shopper thought about getting the grille, but then left it behind.

Get the latest TTAC e-Newsletter!

52 Comments on “Junkyard Find: 1978 Mercedes-Benz 300D...”

  • avatar

    I would appreciate some feedback from the readers of this post. I recently saw a 1984 300SD for sale in my local craigslist for $1500. The ad said the engine and transmission were fine, but that the turn signals and heater fan did not work. Also, at least one of the front and rear windows was broken. They also said the odometer quit at 210,000 miles. Other than that, from the pictures the car actually looked pretty nice. Suspiciously, the rear of the car seemed to be painted a slightly different shade of puke yellow than the front. I guess I was wondering if I should have bought it. It certainly didn’t last long on CL. Are these mercedes diesels like those S-class and BMW 7 series from the late 90s-early 2000s, in that they look nice, but you will go to the poorhouse with all the maintenance costs? I’ve always wanted a diesel, and the only thing that put me off from the 300SD was the tank-like sound of the engine running.

    • 0 avatar
      DC Bruce

      The short answer to this last question is “no.” These 1980 cars were designed by engineers without much regard for cost. So, if one screw would hold something on just fine, three screws would be even better. What happened to Mercedes in the 1990s was “Lexus” which delivered a lot of quality (though not a lot of prestige) at a much lower price. M-B realized that it had to be somewhat price competitive, and its initial steps in that direction were not good.

      My daughter’s boyfriend has a 240D which he still tools around Los Angeles in. Given the basic simplicity of the car (no electric window lifts; manual transmission) and the very high quality of the materials used, inside and out, and that he’s in California, the car does fine . . . although it’s not happy being driven over 65 mph. Typical highway mileage is around 35 mpg.

      Diesel engines — even the best — are vulnerable to use of cheap oil (not “SD” service rated) that is not changed enough. The engines are high-compression, so clearances are tight and lubrication is crucial. Also diesel fuel filters must be maintained to avoid injector wear. Probably before buying one of these cars today, you should get a lube oil analysis which will tell you what kind of shape the engine is in — although a drive will tell you something as well. An engine rebuild could be very expensive.

      The turbocharged 5 and 6-cylinder engines in the SD are more powerful than the N/A 4 in the 240D but, apparently just as durable, turbo notwithstanding. Obviously any car of that age is going to need its rubber parts replaced: hoses, bushings, door seals and the like.

      • 0 avatar
        Athos Nobile

        “Diesel engines — even the best — are vulnerable to use of cheap oil (not “SD” service rated) that is not changed enough. The engines are high-compression, so clearances are tight and lubrication is crucial.”

        You got half of that right.

        Diesel engines need a lot of oil changes because as you said tolerances are tight.

        But also because the produce a LOT of soot and corrosive components, which if not controlled, will destroy the engine.

        Regarding oil, good quality diesel oil needs to have a high TBN. The amount of that additive is the one the main indicators on how long it’s going to last.

        Diesel engines are lovely, almost magical machines. But maintenance is MANDATORY. You can’t really mock around with that.

    • 0 avatar
      bumpy ii

      These won’t put you in the poorhouse unless you’re already there. However, these cars are NOT tolerant of indifference and neglect like an ’80-90s Toyota or Honda. They can be reliable daily drivers, but you can expect to sink several thousand dollars in rehabilitation costs to get there. As with most older cars, you really want to buy the best condition possible.

    • 0 avatar

      I have an early 220D and the heater fan would give me pause. It is buried deep, deep in the dash. Basically you have to take almost the whole dash out to get to it. The part isn’t cheap either. If you can DIY it then probably take a weekend but paying someone else would be a no go.

      • 0 avatar

        A 220D is likely to be the previous model, the W108.
        R&Ring the blower motor in a W123 is a piece of cake. It’s accessible in the front passenger footwell.

    • 0 avatar

      old mercedes are a lot like old vw’s porsches and anything german, if you have the time and patience to scour junkyards and can fix most of the things that break on the old beast the dog will run forever…. i have owned and loved several 123 chassis diesels and have clocked over a million miles total on said cars …. nothing on those cars will beat you up like an afternoon working on a modern jap car or anything else modern with electronics that require a degree from mit … run synthentic oil in the crankcase, transmission, rear axle, and don’t even think about fixing all the oil leaks, old german cars mark thier territory much like dogs … it was a lot more fun running the old diesels in the old days when diesel fuel was dirt cheap, but they still get great mileage for such a large tank … the all time best were the 1985 300D and 85 300 SD … if your gonna send your kid out in the world to drive nothing is safer than the old diesels … these cars have character and must be treated as such, i try very hard not to piss off my old 123 …. if you must have a good ac unit look elsewhere, i have 3 benzes and when it gets hot we drive the old ladys dodge ram which has a great heater and a real a c unit, she loves her 560 SL but love fades when it’s 115 in the shade here in az….many years ago i run a benz service outta my garage and very seldom saw major problems, mostly stuff like vacuum leaks and such… good luck finding a pretty neet old daily driver

  • avatar

    These things are popular with the waste veggie-oil crowd. I’m not sure why you’d spend $5k on converting such an old car, but to each his own.

    How many MPG do these old diesels get?

    • 0 avatar
      Dr. Kenneth Noisewater

      My 300SDL peaked at about 32MPG on the highway when I owned it, overall MPG was closer to 25.

      I donated it at 426k miles, repair costs (including collision damage) exceeded its sale value, and I wanted something with a warranty and more reliability.

      The W123/124 may be more legendary for build quality, but the W126 I think was the nicest Benz, and has held up best over time styling-wise. I would _LOVE_ to find a cheap mint 350SDL with a bad motor and convert it to electric, if I had the time, money and skill.. :p

    • 0 avatar

      It doesn’t cost anything near $5k to convert an old diesel to run on waste vegetable oil.
      In fact, you can just pour clean, filtered WVO into the fuel tank of most old diesels and they’ll run quite happily.

    • 0 avatar

      My W115 gets 20-21 mpg.

      The W123 with the same engine (1977-1981, the non-turbo version such as is shown here) should get about the same.

      They’re also … quite slow, by modern standards. 0-60 in about 18, if the transmission is in good shape.

      The turbos like Mr. Noisewater’s below are considerably faster (~125hp vs ~77hp) and as far as I know, equally economical if not slightly better., in the 123 body.

      (People say the W126 gets better economy for aerodynamic reasons, but I have no personal experience.)

  • avatar

    I had a 1985 300TD (bought it back in 2000 or so) with 125,000 on it (low miles for this thing). Yes, it was slow getting up to speed…the term “glacial” comes to mind. But my God, was that a tank on wheels. Given today’s relative tinny build, you could certainly feel the weight and presence of the vehicle. For the years I owned it, maintenance wasn’t too bad, but I made sure to find a really good mechanic in town who understood these beasts. Mine was gold metallic with those classic Bundt wheels. Once up to cruising altitude, it was a great ride…not sporty, but I guess the best term would be “quality.” You could still tell you were driving a machine made to higher standards. True, today’s diesels are much more refined and quiet under power, but I somehow enjoyed the honest rumbling of that industrial-grade motor. I catch myself looking today at a solid, clean example…

  • avatar

    We owned an 84 for some time & thoroughly enjoyed the car. Once it gets rolling on the highway it’s a wonderfully smooth car. However, I would say that unless you are capable of working on it yourself or have a sympathetic local MB shop (we were fortunate with the latter) you should steer clear.

    The windows, as with a lot of other parts on the car, are actuated by vacuum and problems can be difficult to diagnose and fix. Tires are also an expensive issue as the extreme front end weight of the mighty 5 diesel means you have to buy the good stuff.

    • 0 avatar

      “The windows, as with a lot of other parts on the car, are actuated by vacuum and problems can be difficult to diagnose and fix. ”

      What? No.

      The locks, yes.

      The windows are electric.

    • 0 avatar

      I have a couple of friends who drive W123s and take to a local independent Benz shop. The owner makes his big bucks off of his wealthier customers and does work fairly cheaply for his old school diesel folks.

  • avatar

    I worked on one of these for a friend last summer. That OM617 engine is bulletproof. The rest of the car was easy to work on; quality fasteners, easy access to engine components, cheap and readily available parts. Just watch for underbody rust. They coat the underside for noise, and rust can form under the coating. Nothing you can’t fix with some aluminum sheet, epoxy, and a pop riveter, but watch for it nonetheless.

    Like Murilee said, it’s not super luxurious like Mercs are today, but in my estimation it was a good car. It floats like a Panther and, except for the considerable turbo lag, hustles pretty well. I also like the looks, and a well-maintained W123 diesel has character in spades.

  • avatar

    I did my first on public road driving in my mom’s 81 240D 4-speed, manual everything, one mirror, aftermarket faux MB 14″ alloys, but by gar it’s a MERCEDES!!!! Slow, but what a tank. The only thing I’ve driven that’s been anywhere in the same area code in terms of that “bank vault” solidity of the W123/124 cars were Volvos of that era.

    I still have deranged ideas of cobbing together a 4-speed turbo 300D or TD WVO conversion, but the prices are out of my project budget area (I want my two dollars!).

  • avatar
    Jeff S

    I doubt it was the engine that caused this car to end up being salvaged. More likely it was that someone did not want to put the money into it to fix it up or possibly this car came out of an estate or had been sitting around for a while and was donated to charity and sold at an auction to the salvage yard. Someone might yet take the diesel engine.

    @Murilee-I went back in your prior articles and read the one about the 57 Chrysler Windsor 4 door. My parents had one just like that except it was dark metallic blue with a white top and white trim. We moved from Dayton, OH to Houston, TX in August of 1958. I was number 3 son and sat in the middle of the back seat between my two older brothers. That Fall my father traded the Chrysler in on a new all white 9 passenger 1959 Plymouth Sport Suburban station wagon with factory air which you need in Houston. Someone in Hempstead, TX bought that Chrysler and had it painted all white. I saw that car being driven around for the next ten years. The metallic blue had faded bad which was typical of a lot of metallic paints of that era. For years my parents bought cars without metallic paint. Today metallic paints are much less likely to fade.

  • avatar
    Pete Kohalmi

    We had 4 different W123s (3 240Ds and a 200E direct from Germany) in our family growing up. They were painfully slow but the diesels had this air of invincibility about them. It felt like a tough, rugged engine that would be put under the hood of a Jeep or another military vehicle. They didn’t like starting in the cold though. If they weren’t plugged in at night–uh oh.

    It’s tough to put into words, but the entire car felt like it was built to last for ever and ever. From the “pleather” upholstery to the way the doors slammed shut to the way all the control moved with satisfying precision. This was a car engineered and built by people who cared about their legacy–as if they wanted to leave something behind long after they were gone.

    • 0 avatar
      bumpy ii

      Local Craigslist a few months ago had an ’80s Cherokee with an OM617 under the hood. There are commercial adapter kits, of course.

  • avatar

    I had an ’83 300SD, (the one with the short S class body). I traded it in ’92 with 135K on the odometer.
    The engine was bullet proof, but the transmission had died at 99,000. This was so long ago that the Mercedes dealer put in a factory rebuilt for $1800, about what they charge today for a minor service! I had to replace the vacuum pump twice, or no vacuum for door locks, and HVAC controls. At the end I too had electrical gremlins causing some problems. I would average 26 mpg with a combination of 70/30 highway over city driving. I finally traded it for a Lexus LS because I couldn’t take the SLOWWWWWWW acceleration and because morning starts would wake my family and the neighbors (small lots, close together). With proper maintenance the engine will run forever, but I’m not sure that everyone would want it to.

  • avatar
    Steven Lang

    Eddie Alterman provided a pretty solid synopsis of the W123 models.

    I bought a silver 83′ 300TD for $1000 at a public auction not too long ago. Great interior. No rust. Records. It has a few annoying issues that are reflective of the age. The vacuum system is a constant struggle and I just don’t have the time to drive it on a frequency that merits my keeping it.

    These cars definitely do have an enduring quality about them and my home state of Georgia seems to be a haven for grey market Benzes.

    The big issue with any W123 is selling it to the right person. This often requires me to be the equivalent of an Israeli airport security screener. Since fewer people are fully capable of providing the attention and quality parts that these vehicles need to stay in their prime.

    I have probably dissuaded a dozen plus potential buyers who simply wanted a low maintenance vehicle for a family member or were seeking a low operating cost proposition through a WVO or biodiesel set-up.

    The W126 models are also on the same boat when it comes to the ‘right buyer’ paradigm. The rear-wheel drive Volvos have also entered the same transition from an affluent owner’s enduring runabout to enthusiast owner who has money or time to spare.

    At the moment I also have a well kept 94 Infiniti Q45 and a 94 Lexus LS400 along with a 1993 Volvo 940 turbo wagon. I personally prefer the first two to the common Benz W123 and W126 models. Ten years of engineering enhancements and lean production can yield an unquestionably better product.

    But if I had to choose between all of those vehicles and the Volvo 940 Turbo wagon that was recently traded in for all of $575, that wagon would be in my garage. With a few light modifications, a 940 wagon can offer a surprising combination of solidity and utility without the price premiums that come with an old halo vehicle.

    A guy who bought a 940 sedan from me seven years ago actually gave me two nice cloth seats and a new head for that Volvo wagon. Given that the old owner replaced over a dozen important parts on that Volvo within the past year, I should have a nice cheap hauler for my local trips. Or I may just finance it. Just like I did to a burgundy 94′ Volvo 940 wagon last year.

    So long as you have an owner who understands that 20 year old vehicles need to be tended to, these old Volvo wagons usually make the note.

    • 0 avatar

      +1 on all counts. Volvo 940s are about the best car ever made for long-term ownership if you have a clue – as I have said before, they are like a Panther that doesn’t suck. Especially on a base N/A 940, what is there to break?? Nothing like the solid feeling of a Mercedes though, they were engineered to be easy to assemble and you can tell every time you close a door. Super easy to take apart to fix though.

      Old MBs are great, but they take a LOT of care and feeding. The biggest nightmare with them IMHO is that awful bought in from Chrysler automatic HVAC system. I got the one in my ’79 300TD working properly, but it cost a lot of money and time. It always amuses me to think that car cost new in ’79 just about exactly what my folks paid for their new house in ’78. And what LUXURY, the car had A/C, power windows and locks, and a manual sliding roof. And a stereo with AM AND FM! Golly! 0-60 in right on 18 seconds once I got the old girl running right with the valves adjusted properly. Sold it to a guy on the other coast who wanted to run it on WVO. Go figure.

      The only way to deal with the vacuum system is to go through and replace every single one of the rubber junctions. They are not expensive, but there are a bunch of them. Do that, and it will work like a charm for ages.

  • avatar

    The Weirs were a frugal sort.

    Deidre went to fetch some groceries. She bundled herself up in layers on this cold and blustery October morning. There would be no heat on this ride.

    She climbed into the Benz, and turned the key to the “run” position. She watched the “light bulb filament” light illuminate on the cluster as instructed by her husband. The ear-piercing shriek of the buzzer sounded “EEEEEEEEEEEEEEEEEEEEEE” as the glow plugs did their warming thing. After a few seconds, the note of the buzzer became very disenchanted as lights slightly dimmed “EEEEEeeeeEEE___eEEEEErrrreeEE”. Deidre responded “Well someones an ornery cuss this morning!” before twisting the key. The familiar sound, akin to a light duty commercial truck, confirmed that the engine had lighted.

    She put the car in gear, and sortied to the Safeway across town. She shivered, and it prompted her to fuddle with the fan switch in a vain attempt for warmth. She shook her head in disapproval at her husband Charley. He was, no doubt, enjoying functioning heat in his Jeep somewhere. She recalled the exchange they had when she brought the malady to his attention. “Yeah, it looks like the fan is shot. I’ll have to fix that when it gets warmer so I can work on it.” To which, her response was simply laughter at the thought of working HVAC just in time for warm spring.

    The Benz hammered it’s shifts across town. Deidre accelerated briskly in anticipation of the dreadful hill that was now in sight. She took her place in the right lane as the behemoth labored up the steep slope. She was promptly passed by her penny-pinching counterpart in a Prius. The grey-bearded man in the Prius observed the struggling Benz quizzically as he passed. The expression he wore on his face appeared to Deidre as “I’m glad I’m not driving that piece of crap. That poor woman.” Once again, Charley’s rationale was called into question. “Buying a new car to SAVE money just doesn’t make any sense!”, he would say if he were here. The big underpowered beast was hardly the mileage marvel Charley seemed to wish it be. It had turned out to be merely “OK” in that aspect. She rolled her eyes at the thought of the impending fill up with the ,now, pricey fuel. The oily nozzle and hose at the gas station would no doubt, ruin more of her clothes, and make her hands stink for hours.

    Like an automotive Dr. Jekyll and Mr. Hyde, the Mercedes’ smooth cruising demeanor transformed back into the clattering diesel as she looked for a parking spot. She procured her store-branded items and made the uneventful, although cold, return home.

    At the house, Charley inspected the items. He scoffed at the 20-pack of chewing gum that had been purchased. “We’re not going to be flying THIS much.”, he balked. Deidre proclaimed that it was on sale, which put him at ease….sort of. The Weirs packed into the taxi, and headed to Denver International.

    After 4 weeks, the Weirs returned. They had spent a nice holiday in the old country. Charley awoke in the mid-afternoon after sleeping off the jetlag. He inspected the homestead. He found his Jeep had a flat, which he expected, since he had been dealing with an ongoing rim leak. He topped the tire off with his trusty plastic compressor. He wanted to check the 300d as well. The battery was likely low, since it was already flaky. He opened the door of the Benz, and was halfway into the seat, when he immediately aborted his mission, and lept out of the car. He was dumbstruck by the stench of piss. Rodent feces were everywhere. The little turds adorned every horizontal surface along with small sticky puddles and stains. “AAAAAAAAAARGGGGGGH!!!!”

    The flatbed driver hooked up the chains. He wrote Charley a check. He grimaced while reaching into the putrid cabin to work the steering.
    “So I guess that’s how you kill these things.”

  • avatar

    Crabspirts – good story. I’ve owned two of these, an 83 and an 84 both 300DTs. Yes, they were built like Panzer tanks. And yes, once over 20 years old the vacuum stuff started to fail due to bad hoses and accumulators. Injector hoses also started to leak. I have several holes in my black top driveway to verify this. I had no idea diesel fuel was so corrosive. They were wonderful cruiser cars for long trips provided the cruise control was working. MBTex must have been a WWII body armour invention for the Wehrmacht.

    They were the perfect sized car. Mercedes should make a modern version.

  • avatar

    Last summer I went to look at a 1987 TDT wagon for sale by this guy who lived by my mom. I was interested and went to look at it. Turbo diesel wagon with RWD was so tempting. He let me fiddle around, explained the story (he bought it from Vancouver and drove it to Edmonton here about 7 years ago – on the Coquihalla highway on the way here, a fuel line broke and crapped diesel all over the place and he wasn’t sure if that caused permanent damage but I said it probably didnt because diesels run lean anyway) and the amounts he’d spent to keep it going over the years. It was a US car, in miles.

    I test drove it and discovered some stuff too. Felt very solid and awesome except there must have been something wrong with the transmission because the engine would rev and the car would take awhile to get going, and also the steering wheel was needing to be turned like 20° to get it to go straight. I explained my situation and why I was interested and we discussed it frankly. It was good because he wasn’t tring to “sell” me the car. He ended up recommending I don’t buy it, and I sort of reluctantly agreed. Kind of unfortunate, but at this point in my life and career, there’s just no room for a third car… would have to get rid of my ’91 740 which was part of the plan at the time. Oh well, I hope it went to someone who cares about it.

  • avatar

    We bought one for our son in 1999 for the princely sum of $1500, but there were 3 grand in receipts for a rebuilt engine in the glovebox. It had 80K on the rebuild at time of purchase.

    It was t-boned by a drunk, 45 degree hit to the driver’s side B pillar that pushed it in 6″. Son walked out without a scratch. The back window popped out in one piece, but both passenger doors opened and closed perfectly.

    The engine and tranny was sold to a good friend who swapped it into his ’78. He just had a gorgeous Glasurit paint job applied a couple of years ago, and that engine probably has 250K on it. Still runs like a switch watch and doesn’t leak a drop.

    the NA 5-cyl automatics have liesurely acceleration at best, but are easy to maintain and maintenance parts are reasonable, brakes are a cinch to replace.

    I ran a turbo 1984 300D between 2002 and 2011. It was the most reliable car I ever owned. If you have a choice between the two, get the turbo. It’s well worth the increase in power and efficiency. Mileage will be about 23-25 in Bay-Area style commuting, (50/50 stop & go and 55-65). Mine went to 417K before I sold it to the local PNP, but it was never seen inside the yard. Hopefully someone snagged it and kept it on the road. Tranny had been replaced at 79K and still shifted like butter. I never changed the tranny fluid in the 170K I drove it.

    The biggest flaws are in the climate control system, turbo oil drain tube leaks, cabin water leaks, and occasional vacuum issues. Keep the valves adjusted, change the oil at recommended intervals and it will take a huge amount of use. I only got rid of mine when the clearcoat and interior got so bad that I couldn’t justify restoring it. But is did serve me very well, and I have an ’82 300sd waiting in the wings as a spare car.

    Get familiar with diesel discussion and do some searches to educate yourself about the car. They are very helpful over there, and will save you a ton of money in the upkeep of your car.

    Hope this helps!

  • avatar

    Ah the W123. Brings back good memories. For a couple years I was the owner of a used ’84 300D which was the sedan version of the chassis with the 3.0L inline 5-cylinder turbo-diesel version of this engine (as I recall, the ’78 did not have a turbo but I could be wrong).

    It is indeed a tank. A very solidly built car. A lot of folks will say that the W123 was the last bank-vault Mercedes, built to a high standard without consideration of cost. The 300SD of the era was on a different platform, the W126 I believe, which is also pretty highly regarded.

    Even the turbo version was pretty slow. This was the ’80s so of course it has a big turbo with lots of turbo lag. Moving off the line is quite slow until the turbo spools up and starts generating some boost; then it starts to hustle. But if you put your foot down when the engine is off boost, you can be waiting quite a while for that to happen. To my chagrin, the 300D was only sold in the U.S. with a 4-speed automatic transmission. Would have loved to have a manual in that car, but you have to go back to the supremely more gutless 240D (also available in W123 platform) to have a manual. And I’ve been tempted to do so a few times.

    A major quirk of this car compared to modern cars is the use of vacuum to operate certain systems. Though the windows and sunroof were electrically operated as in modern cars, the “power” door locks and automatic climate control system were vacuum-operated. The car had an engine-driven vacuum pump and a vacuum storage tank mounted in the trunk which would allow some operation of the door locking system after the engine had been shut off. Naturally, vacuum leaks play havoc with the system and cause all sorts of strange behaviors with the door locks and climate control. The car has seemingly miles of vacuum hoses. Owning this car made me purchase a hand vacuum pump and gauge for troubleshooting and the factory service manual has vacuum hose routing diagrams that look like a normal car’s wiring diagrams.

    I also found out one day that, since the plunger on the fuel pump that is used to shut off the fuel and stop the engine is vacuum-operated (via a vacuum valve attached to the ignition switch), if you have a vacuum leak, turning the key off will not stop the engine, which will happily run on indefinitely until you run out of fuel. Mercedes, clearly aware of this possibility, thoughtully provided a manual engine stop lever on the injection pump which you could get to in just such an event.

    I also recall oil changes requiring 2 gallons of Rotax and a huge canister-style oil filter instead of a spin-on type like we’re used to today.

    Cold starting with temps in the 20s was often an adventure, usually requiring more than one activation of the glow plugs. Then it would catch and start running on two, maybe three cylinders before all 5 got hot enough to join in as well. Even then, you got the typical cold diesel white fog from the exhaust and acceleration was much much slower than normal until the engine started to get warmed up to normal operating temperature.

    The car drove very well and was mechanically very sound and reliable. The MBTex seats held up great. My car had a couple minor electrical niggles especially in very cold weather and of course I had to chase down and repair some vacuum leaks soon after I bought the car but other than that it was great. Those engines will run almost forever with proper maintenance. I always heard from others that the automatic transmission was the mechanical weak link of the car but I never had any issues with mine.

    As you can see from this post, I have fond memories of the car. Buy the best one you can afford and maintain it well. I miss that “klatta klatta klatta” sound and of course the range afforded by the massive 21 gallon fuel tank.

    • 0 avatar

      Another issue I recall is that, typical of Euro cars of the era, the A/C was pretty underpowered for American summers (at least mine was even after replacing a leaking expansion valve and having the system re-charged with Freon). The car actually had a Delco compressor as I recall…

    • 0 avatar

      The trick for cold starting is to upgrade to the new style glowplugs and the fancy electronic control box with “after glow” that keeps running them after the car starts. Mine would start easily at -5F after that upgrade. Fairly cheap too, <$200, and mine needed a new glow plug relay anyway.

      • 0 avatar

        One way to make them start cold is to put a couple gallons of unleaded in when you fill up with diesel. I wouldn’t be easily convinced myself, but this is what I did with my old 240D. It worked a treat, and the car ran pretty much the same after starting much more quickly. Is it good for long term durability? I don’t know, but the guy I sold it to drove it for years before parking it on a farm when he lost his license. A couple years later, a relative needed a car and it started up with just a new battery and went back into service.

        I sold it because it was an automatic, and I didn’t trust the transmission after it needed to be rebuilt the second day I owned it. I don’t like driving automatics anyway, and it was slow even by the standards of the other slow cars I’d owned. The guy I sold it to bought it to replace a Mustang GT, which must have been quite a change.

        • 0 avatar

          In the northern part of the US, diesel is “winterized” during the cold months by blending it with kerosene.

        • 0 avatar
          Kevin Jaeger

          A relative had one of these (a 300 turbo) and eventually parked it in his field after it had accumulated a number of issues. Exhaust leak, wonky shifting, vacuum problems and ultimately brake failure.

          It looked pretty forlorn after a couple of years but when my son asked about the car he was told he could have it if he fixed it up. I was pretty skeptical but if my son was willing to give it a shot I said I’d help.

          We charged the battery and strung a long series of extension cords out to the block heater and it reluctantly sputtered to life in a big cloud of smoke, sounding more like a 1940s tractor than any type of modern car.

          We tracked down the vacuum problems to a simple O-ring between the master cylinder and brake booster. The brake problem was just a leaky caliper – fixed cheaply with a reman. $150 for a downpipe and the exhaust was fixed. After a full day of washing, cleaning, waxing and chrome polishing it even started to look like the old classic it used to be. Eventually did a valve adjustment and put in new glow plugs and it starts and runs like new now.

          I never would have believed it, but for maybe $500 in parts and a lots of time that car has been the most practical, dependable student car one could hope for. Three years later it just keeps chugging along.

          • 0 avatar

            Yes, they are practical if you can invest “Sweat Equity”…time and knowledge in place of cash. If you had to pay someone to keep such a car going, it would very quickly nickle and dime you to death.

    • 0 avatar

      “I also recall oil changes requiring 2 gallons of Rotax and a huge canister-style oil filter instead of a spin-on type like we’re used to today.”
      Do you remember the copper washers that went under the bolts that held the canister lid on. Mercedes filters would come with new ones and a third large one for the drain bolt too.

  • avatar

    I had one of these for a while. The most fun you can have in a heavy car with all of 88hp. ;)

    I gave it up because I didn’t have time to deal with the maintenance, if I was going to do it myself, due to a heavy travel schedule…these cars will run nearly forever, but you do need to pay attention to maintenance. A W123 is a solid and well-thought-out vehicle, though. When I needed to replace something, disassembly and reassembly were not the exercise in frustration I had suffered through with other cars.

    However, if you’re going to buy one, keep in mind, “there’s nothing as expensive as a cheap Mercedes.”

    The 216K on the odometer is likely due to that being the point at which the odo quit–they are known for being a weak link in these cars. Mine was non-functional, as was the fuel gauge; I just had to top it off every few days to ensure I wouldn’t run dry.

    (Edit: I did have to use the manual stop switch at least once! My grand plan to replace all the vacuum hoses never quite came to fruition.)

  • avatar

    The 300D probably quit working in disgust. Having shouldered the embarrassment of glued-on fender chrome for long enough, the indignity of an Emperor Pinocchio sticker tipped the balance for a proud car from West Germany.

    • 0 avatar

      National Socialism (German: Nationalsozialismus) in full, was the ideology of the Nazi Party in Germany and related movements outside Germany. Lots of trade unions there, too.

  • avatar

    One of the first jobs I had in high school was as a pump jockey at a nearby garage. It was one of the few stations in the area that had a diesel pump. We lived near an affluent area, although my family certainly wasn’t wealthy, which is why I was working as a pump jockey. I remember these cars well from back in the day when they were new, or very nearly so. The original owners were almost all uniformly jerks…never did get a tip from anyone driving a diesel Mercedes. At the time the most generous tippers were older people driving new Lincolns and Cadillacs.

  • avatar
    Athos Nobile

    “The price tag for a new 300D in 1978 was $20,911. That’s close to 75 grand in 2013 bucks, for…”

    what was essentially a taxi cab.

    I fixed your text a little bit.

    • 0 avatar

      Not just a taxi cab, a car designed to be used and used and used and repaired and used and used and used.
      Those traits happen to make the car eminently well qualified for the life of a taxi, especially when ordered in a bare bones configuration that they never offered in the US.

      I suspect you have never had the pleasure of a W123 daily driver. That’s a shame.

      And I second the suggestion that the odometer on this junkyard dog died long before the car did. Don’t reset them while the car is moving.

      • 0 avatar
        Athos Nobile

        I haven’t had the pleasure. With 88HP on a car weighting 1500+ kgs I’m not looking forward to have it either. Have seen only 2 on the streets down here.

        Now if we talk about a W124 300E, that’s something I’d love to try. Sadly the ones I’ve seen at the auctions have all the wood trim cooked and cracked. And they still command some coin.

      • 0 avatar


        I’m not sure how much more stripped an early 240D could get. No sunroof, no electric windows, no A/C, 4spd manual, no passenger side mirror was not uncommon in New England in the ’70s and early ’80s, as those things were all options. I suppose it could be a 200D or a 220D without power locks – I think the power locks were standard here.

  • avatar

    Note the single, double, and triple square dots in the speedometer.
    Simple but effective engineering solution showing maximum shiftpoints.

    These cars were full of thoughtful engineering touches like that.

  • avatar

    This makes me sad, partially because my one previous owner (he ordered it new) 1983 240D just turned 217,000 this week and still glistens like new.

    They all leave the factory the same.

    I love diesel 123s- this is my fifth. It wakes up every morning with a cheerful chortle and teaches me to appreciate every tenth of a horsepower. And it’s fun to play crazed Parisian cabbie.

    • 0 avatar

      All this talk makes me want one again. I could use it to go to IKEA and buy some nice sofa cushions, which I would need after my wife, who was not in love with my first W123, banished me to the sofa for a month. ;)

Read all comments

Back to TopLeave a Reply

You must be logged in to post a comment.

Recent Comments

  • ToolGuy: When that second ad was shot in 1992, Donald Sutherland was only 57 years old. I still hear him doing...
  • Crosley: The AC really was terrible, I actually figured out a way on a Volvo forum to make the condenser fan always...
  • SnarkIsMyDefault: Should call it the Corolla GRrrr! Some are already calling it the Grolla..
  • Lie2me: Yes, those two T-Birds are far more interesting then this Volvo Hey, Murilee, will we see the Thunderbirds in...
  • Crosley: I had a 240 wagon, loved that car. So easy to work on, simple design, and everything felt solid and...

New Car Research

Get a Free Dealer Quote

Who We Are

  • Adam Tonge
  • Bozi Tatarevic
  • Corey Lewis
  • Jo Borras
  • Mark Baruth
  • Ronnie Schreiber