1983 Mercedes-Benz W123 Sedan nonturbo from North America - Comments

Injector leak from return lines.

Radio and dome lights do not work.

Instrument cluster lights do not work.

Fog lights do not work on one side.

Lazy shifting automatic transmission.

It is average in durability, despite people's many optimistic praises. Germans definitely do not have their electronics correct. There are many electrical gremlins. A Toyota of similar vintage is much more reliable in the electronics area.

To start off, power door locks are air, so that is prone to problems when a leak occurs.

The dash lights are very dim, and sometimes do not work at all, despite replacing the potentiometer on the gauge cluster.

Clock sometimes works and sometimes not.

Dome light and radio cuts out from time to time.

Mechanically it is decent, but rust develops in the wheel wells.

The injector return lines (3.2mm ones) are prone to leaks. These lines are secured by barbs (no clamps) at the injector. They are also tiny and braided, and available only from Mercedes dealers. Leaks here can be a fire hazard. It would have been better if they used hard metal lines instead of flexible rubber return lines.

Performance wise, it is very slow, barely getting up a steep hill. Mileage is also not so great (24mpg) probably because of large weight. Its only redeeming quality is that it is immune from emissions requirements (even though it probably pollutes more than a regular gasoline). That opens up the possibility of an engine upgrade without government intervention.

If the barbed lines leak, why don't you just put hose clamps on?

The fuel return hose is cheap and easy to replace. Try to light diesel fuel with a match, then explain how it's a fire hazard!

You cannot put hose clamps on the return line hoses. There is not enough room at the injectors. Besides the leak occurs at the hose itself due to old dry-rot age not where it meets the barbs. Although it can also leak at the barbs also if you try to reuse old lines. The factory Mercedes braided return lines are not cheap at all $12 (US) per foot. Diesel may not be a fire hazard for the previous reader, but the inspection authorities will think otherwise. Also who wants to smell diesel coming out of the engine compartment not to mention get even worse gas mileage?

I used Tygon line on mine, go to a lawnmower or chainsaw shop to find it. It's cheap, and mine hasn't leaked at all.

He has bought a car with nearly 300,000 miles on the clock and seems to expect it to be perfect!! Plus he wrote this review after only 100 miles!! A well maintained W123 is just about the most durable car made. I have a 1983 Benz W123 and a 2003 VW Polo TDI I choose the Merc every time. The VW has become transport to my office and back nothing more.

You should not be driving about with a Diesel leak. Think of other road user especially Motorcyclists who could get killed by your lack of Maintenance. Please do not endanger other Road users.

There are a couple of classic rust areas on the W123s, but minimal attention will stop the rot.

I think the "permanent" cure for the injector return lines is Viton tubing - I've had some on mine for a couple of years now, and it can't be much more than what a Benz dealership charges.

I've seen an LED mod for the dash lights - but be sure the rheostat on the light panel isn't bad, even when new, by shorting the terminals then checking the brightness.

Benz used vacuum for many things on this car, from door locks to engine cut-off. A cheap hand vacuum pump with a gauge is well worth it for troubleshooting.

My uncle repaired his with plumbers tape. No more leaks.

Your instrument lighting can be fixed by bypassing the dimmer resistor, easy job. It will have disintergrated into a cocaine like powder! The crap Mercedes Benz produces now pales in comparison to the w123.

Anyone who has been driving the old MB diesels for any time at all will tell you they were the best cars the road has ever seen.

My wife's 1983 240D had 374K miles when she totaled it last week, and was still going like a champ. My 1984 300SD just turned over 662K miles, still on the original engine. "Mediocre reliability" is a joke.

ANY car this old is going to have things break. That's just common sense.

The return lines are not only available at the MB dealer. I buy it for about $3 a foot from a local foreign car parts store, and it's a 5-minute repair. Any idiot could fix it.

Also, as far as harmful emissions, gas engines are actually worse than diesels, as far as the type of emission they produce.

I have been driving these cars for many years, and wouldn't dream of owning anything else, despite how old they are now. You should sell the car to someone who appreciates them.

I agree with the above poster. Anyone who really knows cars, should know that W123 era Benzes are the some of the BEST!

My 83 300TD is one fine, solid and reliable car. It has over 300k miles and looks great too. It drives smoothly and quietly around town and has more style, character and appeal than the majority of cars in circulation on the roads today.

The 300TD was my first Mercedes and because it was so wonderfully built, comfortably equipped and refined as well as engineered to last for ever if needed it made me an appreciative fan of the newer cars with the Three Pointed Star. As nice as a new Benz can be, the old ones are just as nice to drive.

Mercedes was first, and the way things are going these days, they may be the last.

I suppose that if one were to complain about an old car, comparison should be made to the other inferior cars on the market.. if I may say, I will drive an old benz over any other old model vehicle on the road... any day, any time.

I recently purchased my baby - 1983 300D with WVO conversion. And must say I love it. I cannot imagine owning any other car, let alone driving in any thing else. Also with the reliability of these beauties and the amount of torque a diesel engine can produce. Go ahead and sell that Benz to someone who will love it, and when your new lil car breaks down - we will be there to tow you home. Viva La W123.

This w123 diesel owner does not realize what he/she has, nor does he/she appreciate the engineering that went into this automobile.

I am the proud owner of a 1977 Mercedes Benz 300D that I convinced my parents to buy new over 30 years ago. My parents are both gone, but my "Heirloom" benz keeps moving down the road like the day it was new.

I have every service record for this car going back to the delivery documents from the dealer (even the canceled check copy from my dad!). I figure this car, including original purchase price, has only cost about $1,000.00 per year - not bad.

Oh...about the fuel return lines, anyone with these cars knows that is a routine service item that costs less than $20 and 15 minutes to repair if you do it yourself.

Mercedes Benz Classic Department in So. California can get almost any part needed for this car. I have even had them provide new interior plastic parts to replace the brittled old pieces, not that expensive either.