123 diesels vs. 124 diesels: what to expect?
 

I don’t intend to open a can of worms here, but I would like to get some feedback & opinions on the 124 chassis diesels, specifically the turbo’s (1987 model year only???)

My 84 300D is the first diesel I have ever owned, and in the last 2½ years I have really become a diesel “nut”. I intend to keep the ’84, but would like to get a wagon for camping & hauling stuff around. I know about some of the typical idiosyncrasies of the 124 chassis cars in general, but what other pitfalls are there pertaining specifically to the diesels?

I am already aware of the head cracking problem, but supposedly the new castings don’t crack (or do they???). I guess I am looking for opinions on the overall durability & ease of service as compared to the 123 chassis cars. How durable are the bottom-ends on these engines? What about all the ancillary equipment? I want to *drive* the car, not tinker with it constantly.

I like the fact that I can take off on a 1500-mile trip in my ’84 with 228,000 miles, and not really worry too much about it – it just keep going and going and going…. Could I expect to experience the same confidence with a 124?

Thanks in advance for any & all replies!

Glenn

There was a great thread about this a few months ago, I believe it was started by LarryBible. Great reading for this. Some things covered there were complaints of higher cost parts, fixing a part and having it last for a short while then having to fix it again. The more accessories, the more possibility of problems. They get better mileage, have more power, ride nicer, but can be much more costly. If you buy an abused one you're in for a big task. Buy one only with good records. The confidence should be about the same, but when it comes time to work on it I takes more time and money.

It can be found here

The W124 TD will have more power, especially the 87 with the 603. Better milage, too.

Mine, initial problems with IP aside ($8.10 fix) has been very reliable. Start locked up at 182,000, needed a new belt tensioner spring (why MB doesn't use this sytem on the other engines I don't understand!), and a few other piddly things. Going strong.

Later models have the 602 2.5L five cylinder, so they have less power (still more than a W123) and get even better milage, up to 35 mpg or so.

Drawback is finding one......

Peter

BoostNbenz: Thank you for the link! That thread is great – just what the doctor ordered.

PSFred: Years ago, I rode in a ’87 300D and it was quite impressive. (probably what got me to even ever consider a diesel at all). I’m glad to hear of your good experience with yours – question: is the engine all original, or has the head been replaced?

Also, is the 2.5 (602 engine) significantly less powerful than the 603? (I apologize for being lazy – I could research that myself… :) )

Thanks again guys!

Glenn

Yes, the 87 300D is quite a bit faster than the 300D 2.5 Turbo! You probably won't notice it much in the city, but passing power and highway response is much better in the 87 300D. Drive both and see for yourself. However, the 2.5 Turbo gets better mileage and comes with a few nice things that the later model 124's had - wood on the dash and doors, a rolltop center console box, better front seatback pockets, the "convenience module" allowing you to roll up the windows with the key, updated body side moldings and trunk filler panel, etc.

I love my 124. Much more performance than the 123 that my son owns. I have put about 80,000 miles on it in the last two years with only minor problems. I recommend it highly.

Joe

Don't know about the head, but the rad is brand new, so it may have been replaced. I'll have to check.

Bright and shiny inside the oil filler cap, but then I've run Mobil 1 in it for almost 20,000 miles, too!

Peter

I owned a 123 and a 124. The 124 from 125K to 202K. I would hands down recomend the 124 over the 123 in a heart beat!! Just make sure that it has been cared for.

I simply will not understand why so many people think that the 124 is such a more complicated car to work on. The only thing that went on my car that I did not do so myself were the tires (Walmart) and the ball joints. And I am the quintessential home mechanic with no training. For all the extra safty, comfort and convenience you get in a 124 over a 123, I just don't see why there is a question...unless your concern is economical (we all understand this). Obviously, you can get a 123 for less than a 124.

The only thing I can think of that made my experience different than a few others is that I bought a car that was previously pampered and garaged, it had the smaller 2.5 i.e. more room under the hood, and it was a latter model that benefitted by several years of chasis improvements.