1983 Mercedes-Benz 300SD Turbodiesel

Description for Mercedes-Benz S-Class 1983

Please read this description fully as any questions you have may already be answered, including why I have decided to sell this car. This is my personal vehicle, a 1983 Mercedes 300SD that is in very good condition. The owner prior to me was quite wealthy and had made it his goal to turn this car into a daily driver and although it has some imperfections, that goal of making this classic Benz a daily driver was definitely met in my opinion. I have already driven this car on several road trips of 250 to 500 miles each with no problems at all. The car starts, runs and handles straight and true with no issues and does not smoke on startup or at idle. This car is not a speed demon in town but once it hits over 50mph it zooms right along and loves to cruise between 80 and 90 mph all day long while holding steady temperature and oil pressure. At 80 miles per hour I averaged 24.5mpg and at 65-70 miles per hour I get about 26mpg.
This car has had extensive preventative and restorative work performed over the last 20 months (described in detail below). This car loves to cruise on the highway and is very comfortable on long drives. The cruise control works perfectly, and the A/C blows ice cold. The transmission shifts very smoothly without jarring between gears. With a light foot on the accelerator it shifts to 4th pretty quickly, a heavier foot prolongs the shifting for faster acceleration. The kick-down switch works great if you need to downshift, just press the accelerator to the floor and it downshifts immediately. All windows, hood and doors work fine and the sunroof opens and closes smoothly; even the sunroof air dam works fine.
This car is rust free and has a very solid and true body with no accidents. Here is a complete list of all restorative and preventative maintenance performed on this car over the last 20 months. Almost all of this work has been performed by a Mercedes Technician who specializes in classic Mercedes Benz (detailed invoices are included with the car).

Preventative and Restorative work performed on this car

July 2018

• Oil and filter change including all new filter shaft o-rings
• Liqui-Moly Diesel Purge
• Replaced clear pre-filter and main fuel filter, o-rings and crush washer
• New MANN air filter
• Valve adjustment / valve cover gasket with new wave washers
• Lubricated all throttle linkage points
• Lubricated hood hinge pivot points and both latches
• Window lift rail sliding clip replaced in right rear window + lubricated regulator at same time
• Repaired broken air cleaner mount

September 2017

• Fixed transmission leak: replaced pan gasket crush washers and dipstick seal
• Adjusted aneroid compensator for better performance
• Replaced front transmission crush washers
• Replaced both gear shifter bushings
• Replaced Bowden Cable hasp

April 2017

• New left front brake rotor and wheel bearing kit (under warranty from previous repair) and left steering stabilizer
• Replaced push button control unit for climate control system
• Replaced transmission reverse piston seals

November 2016

• All new General tires
• Replaced both lower ball joints
• Replaced guide rod bushings and mounts
• Replaced upper control arms and sway bar bushings
• Replaced both front calipers, brake pads, and flex hoses
• Full brake fluid flush with DOT 4
• Replaced right rear brake sensor cable
• Replaced both front rotors
• Replaced both front wheel bearing kits and seals
• Replaced idler arm bushings
• Replaced rear sway bar links with upgraded metal sway bar links
• Replaced A/C compressor and drier, compressor fan switch and all A/C o-rings in engine compartment; system upgraded to R134; blows ice cold
• Replaced defrost actuator behind glove box so all vents work properly
• Replaced climate control grill in overhead panel
• Replaced A/C foam cover and evaporator drain on driver's side
• Replaced all 5 glow plugs with Bosch glow plugs
• Replaced old plastic primer pump with upgraded new metal Bosch primer pump
• Replaced all fuel injector return lines
• Replaced rack damper pin
• Adjusted injection pump control rod and linkage
• Replaced turbo waste gate hose and clamps
• Removed and cleaned aneroid compensator bolt at back of manifold
• Replaced diesel return cigar hose
• Replaced all three air cleaner shock mounts and heat shields
• Replaced crankcase ventilation hose
• Replaced both motor mounts including new heat shields
• Replaced engine shock mount
• Replaced upper oil cooler hose
• Replaced oil filter housing gasket
• Replaced oil dipstick bracket which was missing
• Transmission filter replaced, fluid and torque converter flushed with new fluid
• Both transmission cooler hoses replaced
• Power steering return hose replaced, flushed power steering pump, new filter
• Coolant system flushed and replaced with Xerex G-05
• New thermostat
• Replaced all drive belts
• Differential fluid drained and replaced
• Replaced both front door strikers
• New battery
• Replaced cruise control amplifier
• Rebuilt right front window motor
• Replaced right inside door handle
• Brand new Euro headlights (original headlight assemblies are included with car)
• Lubricated all door hinges
  
• Compression was tested at this time and tested okay

Undocumented upgrades and service performed on this car

• The car has a relatively new Bluetooth-compatible JVC stereo with remote control and lapel mic attached, but no instructions. For the life of me I cannot figure out how to turn this radio off, so I mute it when not used
• I believe the Hirschmann antenna has been rebuilt at some point as it seems to work fine
• The front seats are solid and firm and I believe the driver's seat may have been reinforced or had some springs replaced in the recent past, because it is quite firm and does not sag, a common known problem with these older cars
• The rear window seal has been replaced in the recent past as it is pliable, with no cracks at all and looks brand new

Known issues with this car

As with any car this age (35 years and counting!) there are some known issues that the new owner may or may not choose to deal with. Known issues that I am aware of are—

• While the car does not burn or leak oil while driving, as soon as it's parked it leaks about 1/4 cup of oil from the rear main seal. This does not seem to be a major issue and the mechanic who did this major work considered this a secondary concern and told me not to worry about it. But it can make for a messy driveway over time. If you park the car facing downhill, it will not leak at all.
  
• The trunk lock is a little funky and the trunk can only be opened with the key
• The vacuum lock system functions erratically refusing to work most of the time, although the pump located in the trunk does activate. The door lock pump in the trunk has been diagnosed as being stuck closed so it needs to be replaced. This is an easy DIY replacement for the new owner to address.
• Because the vacuum lock system does not work (see bullet point above) if you do lock the driver door with the key you have also locked the fuel door which won't unlock again. So when this happens you will have to use the emergency unlock (only once) to unlock the fuel door (easy to use and found in the trunk) when you need to refuel. It's just easier to not lock the car until the door lock vacuum pump is replaced. I hope this makes sense.
  
• The passenger seat has one motor stuck or in need of attention so the up/down seat adjustment doesn't work properly. The front to back movement and the seat back adjustment motors work fine.
• The front driver's seat is not perfect, it has some wear with only a two minor tears (see photos). As mentioned above, it is solid and does not sag and offers firm support. All the other MB-Tex seats are in very good condition with no wear, rips or cracks.
• The silver paint is a little tired showing micro-scratches throughout. They don't show in the photos but they are there. It seems a previous owner loved to put this car through those aggressive automated car washes and the paint shows it. This kind of thing doesn't bother me but the next owner could bring the look of the car back to life easily as the car is rust and accident free.
• The engine does have some blow-by but I have been told by two Mercedes technicians (one who looked at the car, one by phone) that this is normal for this engine and not to worry about it
  
• The dash is cracked, common for these 35+ year old cars.
• While most of the real wood trim is in excellent condition, the trim on both sides of the steering wheel has some issues ... with some separated laminate (poorly re-glued) and a small piece of the wood laminate is missing (see pics).
  
• Unfortunately, I do not have an owner's manual. These can be found on eBay for about $30.
• I have no service records prior to November 2016.

Parts and tools I'm including with this car

I'm including spare parts and special tools I have to help the new owner keep this car going. Included with the car are—

• Special valve adjusting tools made in USA by MercedesSource. A must-have because without them adjusting valves on this OM617 engine can be very difficult and a hair-pulling experience.
• Two new Elring valve cover gaskets
• Special diesel purge tank made in USA by MercedeSource. This makes doing a diesel purge much easier than any makeshift system you can come up with and lets you see the purge's progress in real time.
• Seven new clear pre-filters (Meyle and Mercedes brand)
• Two new MANN main fuel filters
• One new Mahle canister oil filter
• One new Mercedes brand window lift rail sliding clip … for the next time one breaks (and they do break with age).
• A new Hugo voltage regulator for when it's needed (the Bosch regulator on the alternator is fine with plenty of life left)
• A set of brand new Bosch windshield wipers for when they're needed (the ones on the car are fine)
• An ample supply of Mercedes brand rubber o-rings, crush and wave washers for all your oil and fuel filter changes, and your next valve adjustments you'll need to do for the next few years
• One unopened gallon of Xerex G-05 50/50 antifreeze. There are no leaks at all, this is on hand just in case it's ever needed.
• A sunroof lubrication kit with enough special Mercedes sunroof grease for 2-3 applications or 2-3 cars.

I acquired the car never actually having driven (beyond short test drives) or owned a 300SD, although I did own an early 80s W123 300D decades ago which I enjoyed but I was much younger then and DIY maintenance was much easier for me. I always liked the look of these W126 Mercedes and had convinced myself in the last year I wanted one. I guess it's truly a matter of "be careful what you wish for" because after months of searching for one in decent condition, and now owning and driving this one, it's clear these older classics simply are not for me. To be honest, the hunt was more fun than the catch. I have to admit that my love affair with these older diesels is over, and to top it all, at my age my lower back simply will not allow me to continue performing the do-it-yourself work that is required to own one of these classics. I almost blew out my lower back recently doing the most recent valve adjustment — something I enjoyed doing when I was much younger — and I am still paying the price with Chiropractic visits. I have to face my own reality of growing older (I'm pushing 60) ... so it is what it is. While I have not owned the car very long I did an extensive search to find the best one I could find. There are no hidden surprises and everything I know about this car is listed above. I believe you will be hard pressed to find another 300SD in this price range in this general overall condition. I have come to the realization that someone else would be a better caretaker for this car than I can ever be. I also don't have a garage so the car has been outside since I acquired it, something which bothers me a little. It really needs to be garaged.
This car is offered as-is without any warranty and I encourage you to ask any questions which I will be happy to answer, or to arrange for your own personal inspection. Upon purchase I am requiring a non-refundable $500 deposit by PayPal, with balance to be paid in full by certified check, wire transfer or cash prior to local pickup within 10 days of sale. I will make myself available for a car transport arranged by the buyer, or the new owner can easily drive this car home with no problems.
If you wish to converse with me by phone about this car please email me for my phone number. If you are located near the upstate South Carolina area you are welcome to come test drive the car yourself, it is registered and insured.
I am also advertising the car locally (same description and photos) so I reserve the right to discontinue this listing early. The car is located in upstate South Carolina. I have a clear and clean SC Title in-hand.
Blessings and thanks for reading this very long description.