Mercedes W124 300D

[1990C4S]

Anyone here have a 300D W124? Dennis?

I'm looking at buying a 1986 with lowish miles (120,000).

These cars 'appear' to be slow, and but reliable and can run forever.

Any reason not to do it? I don't mind a car that takes some work...as long as it starts and runs every day.

[otto_kretschmer]

Don't have a Mercedes but I follow Pierre Hedary and sometimes Kent at Mercedes Source



https://www.youtube.com/@Mercedessource/videos

[1990C4S]

Thanks, he gives it a thumbs up...

[jyl]

No idea about the diesel, but I have a gas W124 and it’s a great car. Super build quality. Not too many electronics.

[RNajarian]

I had one of those. Yes a little sluggish even with the Turbo, but a great overall car.

At 120,000 miles and 35 years likely all the rubber will need be replaced, motor, transmission etc.

Sometimes the seats lose their spring. Wood dash parts crack, but all that little stuff can be replaced.

If it’s not leaking oil and a PPI checks out I’d say do it.

[Chocaholic]

Originally Posted by jyl

No idea about the diesel, but I have a gas W124 and it’s a great car. Super build quality. Not too many electronics.

Ditto…my W124 (gas) is my DD and has never let me down.



Hope I don’t regret typing that.

[1990C4S]

I think the gas suggestion might be a better route...as much as I like diesels, the 300D is definitely sluggish.

[1990C4S]

Originally Posted by RNajarian

At 120,000 miles and 35 years likely all the rubber will need be replaced, motor, transmission etc.

That would be the first thing I do.

[speeder]

Sorry for the delay, I was typing out a response yesterday when I got waylaid. I have a 1995 w124 diesel that is sitting outside of the cafe I am typing this from. Completely different engine, though.

I have owned a couple of cars with the OM603 6-cylinder that your car has and they are great. The early ‘90s w124 diesels had a 2.5 liter turbo 5-cylinder that was different from either of our cars.

The people complaining about slow turbo diesels either have a schit mechanic, (or don’t know how to work on them themselves), or drove one that was a worn-out POS. In proper tune and condition, they run very strong. My 1995 doesn’t even have a turbo, (NA OM606), and it performs great. It’s very important to find a shop that understands OM603 motors, they are not overly complex but they have some unique mechanical features. Normal maintenance is the same as any other MB diesel of the era, in fact it’s easier because there is no valve adjustment needed. Your car was the switch over from regular tappers to hydraulic.

[speeder]

Almost forgot the photos!

[jyl]

Diesel doesn’t have the biodegradable wiring harness problem, right?

Replacing W124 upper and lower wiring harness and throttle actuator is rather spendy. I think the supply of OEM parts is gone so you’re buying used or rebuilt or custom fabricated harnesses, and rebuilt actuators. Really nice to avoid that.

[Chocaholic]

I’m guessing it would have been replaced by now as it would have disintegrated to dust some years ago. If it’s like the gas version, there’s a tag on the harness near the battery (may have to pull it out) that shows the year of mfg. Mine says 2009.

[jyl]

Originally Posted by Chocaholic

I’m guessing it would have been replaced by now as it would have disintegrated to dust some years ago. If it’s like the gas version, there’s a tag on the harness near the battery (may have to pull it out) that shows the year of mfg. Mine says 2009.

Sadly there’s still W124 out there with the bio harnesses, or only the upper harness replaced.

Mine has a new upper harness and I have a rebuilt throttle actuator ready to go in.

[speeder]

The harness issue is really a good question; I have not located a date tag on this one and do not know if it shares the biodegradable original harness material with the gasoline models. Fwiw, the wiring all seems great and no electrical problems at this time. Between my first ownership and the person I sold it to in 2020, (just got it back), about 20k miles added. 265k now and runs like showroom new.

[speeder]

Originally Posted by Chocaholic

I’m guessing it would have been replaced by now as it would have disintegrated to dust some years ago. If it’s like the gas version, there’s a tag on the harness near the battery (may have to pull it out) that shows the year of mfg. Mine says 2009.

You’re good to go with that 2009 harness. Which model do you have?

[speeder]

Originally Posted by otto_kretschmer

Don't have a Mercedes but I follow Pierre Hedary and sometimes Kent at Mercedes Source

The Pierre video is great, I don’t agree with him 100% but pretty close. He has a lot of knowledge. He states that my 1995, (one year only), e300 diesel is the best one ever. Having owned so many MB diesels, I agree. Its magnitudes more refined than any w123, (which I also own).

Kent Burgsma has helped a lot of people with his videos and products but a more annoying person has never lived. He has a way of injecting a lot of BS in his videos in an attempt to dumb them down for the masses.

[1990C4S]

The car is not as rust free as advertised. Had to pass. I will keep looking.

Thanks for all the input, I'm watching Pierre pretty regularly now.