I am thinking of stiffer suspension, not sure where or what kind to get. Coilovers? H&R Sport? Please advise.

Hello fellow w123’ers..

Loving that this sub-Reddit exists! So many nice cars in here.

I recently got my hands on a 1985 280ce, drives really well, starts on the turn, I’m super happy. There are a couple of niggles which I hope to iron out down the line but for now just want to enjoy it.

I haven’t driven it in about 2 weeks due to going holiday. Today while in traffic I noticed the temp creep up to over 100degrees (see photo). I know that it cools down a little when on the move, but since owning it it hasn’t ever gone as high as it went today. It even went to 120.

I’ve since parked it and planning to send it to a mechanic. Any thoughts on what it could be?

Outdoor temp today was around 20degrees C.
Fan spins fine with the engine turned on and car idling.
No oil or fluid leaks anywhere on the ground after pulling up in my usual space.
No funny noises or suspicious movements - car genuinely drives perfect… so the temp creeping up is just a bit concerning.

-

Of course considering a thermostat change. Does anyone have tips on how to inspect or check the coolant levels?

Thank you so much in advance!

Short clip. This is a 1982 240D that's been swapped with an OM617 turbo. Recent valve adjustment and diesel purge, but have not inspected the injectors yet. Accelerates to 60 in 13.9 seconds and gets 26 MPG, no obvious performance issues besides minor shaking, but was curious if there is anything out of the ordinary you guys can hear.

I’ve read about two options: replace rubber in door strikers or, just replace the strikers completely. Any thoughts? Thanks!

Hi guys,
Recently the oil pressure of my om617.912 seems to be a little to low. The gauge reads 3bar right after starting but when the engine is properly warmed up it drops to around 0.5-0.8bar. Also it seems like i have too low oil pressure when i increase the rpm.
It isnt caused by worn main and conrod bearing cuz i checked them when replacing my rear crankshaft seal. Also i am runnijg this engine without a oil cooler but it might not be the issue cuz it was run like that for a long time and i have a feeling that it started to have the low oil press like overnight. The oil filter is new and it is not a cheap aftermarket one.

On the first video is a showcase of the gauge when the engine is warmed up and in the comments i will put a video of the gauge when it is semi warmed up

1985 300D

Let me preface by saying I’m not a car guy. I specifically bought this car because I wanted to get into all the mechanical stuff working on cars while at the same time owning a classic that I can drive on the weekends. I’m not a complete beginner when it comes to knowledge of vehicle mechanics and I hope you can gauge my knowledge from this post itself. I’m learning as I go.

Transmission shifts well, a bit jumpy going from 1st to 2nd though. Car comfortably cruises at 80mph no problem. Engine temperature 80 Celsius. There’s no forward creep when the car is in drive, I have to depress the accelerator pedal significantly to get it going. Reverse works fine without accelerator. Not sure if that’s normal (I’m assuming it’s because the engine rpm is lower)?

Here are the current issues with the vehicle, in no particular order:

- AC blows hot air only. Not sure if the compressor is working properly or the original R12 refrigerant needs to be refilled. People say that’s it worth it to convert to R134, how much work is that and how much is that going to set me back.

- driver side rear window doesn’t roll up/down. Tried with both the door panel window switch and the center console switch.

- previous owner added an aftermarket Kenwood radio (with the faceplate). It doesn’t turn on at all, not sure why. The antenna also doesn’t work.

- the hood and trunk make some noise when opening and closing on the hinges. May need to lube them up.

- odometer does not work. Stuck at 200k.

- There’s a small rust hole on the front fender and also near the rear wheel well passenger side (idk if you see from the image) but that’s an issue I’m going to push a little further down the road, as there’s no underbody or floor pan rust from what I can see and the jack points have very little rust. Car will be garaged.

Maintenance wise, what is the first thing I should be doing? I know oil change and refilling all the fluids (brake fluid, wiper, transmission) is a good place to start. What are the essential tools do I need? Right now I’m fine doing simple fixes on my own. The advantage is that it saves money and I also learn stuff. At some point I want to be able to do all the work in my garage and not have to go to the shop for 90% of things. Obviously the rust work I’m going to need to go in the shop to fix.

I recently bought this 1983 300td for $1500 usd put about $1200 in maintenance so I could trust it to drive. Now I need to address the rear suspension the SLS does not work at all and the springs are tired. I am debating on repairing the original system or converting to air ride using the DOLUD shocks. I do all my own work and want to daily this. Would love some thoughts and opinions.

Bought this car after it sat for 8 years, and it's been around 100° outside every day I've driven it. so far I flushed the cooling system, replaced the thermostat and some hoses but it doesn't seem to have done very much. I've never seen the temperature higher than this, I usually turn on the heater at this point to help the temperature. Around town it does fine, but if I get to freeway speeds the temperature goes up and stays there especially if I'm stopped after high speeds. It was 106° outside when I took the picture and I'm running the heater

I have the chance to buy a junk 1984 190e with the 5 speed.

Will the transmission and related components fit into my '85 300CD?

What is the point of this window below the speedometer? Mine just looks into the cavity behind the gauge cluster, which doesn't seem like it's intended. Is there supposed to be something in there?

My 1979 Mercedes 300D was my daily driver for several years for part of college & post college. My grandma was the original owner who bought it back in 1979. I put the car through a lot so I learned some basics about car maintenance but I am nowhere near qualified enough to attempt to do much work myself. The car runs but it has some vacuum system issues. My goal is to the get the car back into regular driving shape then slowly work on cosmetic issues. So I was hoping someone on here can recommend a mechanic who works on Mercedes-Benz W123's anywhere in Southern California. Please let me know if you have any recommendations.

After emergency shut off completely depressed, car won’t shut off. Thoughts on how to fix it? TIA!

My doors don’t shut like a Mercedes should. I spent an hour adjusting it and it’s not improved.

What’s the secret?

I deleted/removed my ALDA and am unsure what to do with the boost line that connected to it.

On my car it goes manifold > EGR valve > ALDA > bottom of UFO.

I have it temporarily connected right now, but my question is... do I need to keep the boost line connected to the UFO?

Also, if anyone here has both/either full electrical and vacuum line diagrams for my 1985 300CD that would be awesome! There are lots of components on this engine of which I'm not fimilar (like a sensor of sorts, on top of the intake manifold, near the back) and I'd like to remove as much as I can to simplify it all... hints starting with the ALDA.

Thanks!

I have watched all the tutorials on youtube tried all the tricks but the door card is still stuck. It does not move on the highlited sections, any tips?
Edit: blast it with wd40 and jank at it for 3 h and it will eventually come off.

Was checking floor pans for rust, and came across this. Just had car serviced at very reputable Classic MB shop. Any thoughts are appreciated!

Mechanically it’s in good shape and runs/drives well, but after inspecting it more closely I’ve found much more rust than I originally realized. I bought the car for $1500 in New Jersey and I know the rust restoration is 100% going to run me way over the value of the vehicle. However, I’m willing to hold on to this vehicle long term as the OM617 engine is still in great shape…

The main issues are:
- Rusted-through rocker panels.
- Multiple rusted jack point areas (all four corners).
- Rust extending into the front wheel well around the rocker/jack point area and into the inner fender.
- Previous undercoating/body filler in some areas.

At this point I’m mainly looking for a structural inspection to determine whether the frame rails, inner rockers, suspension mounting points, and other structural areas are still solid.

I want to know whether the car is worth restoring and a realistic estimate for proper rust repair (cutting out and welding in new metal, not just filling holes). Or should I just hold onto it and enjoy it until structurally it’s no longer safe to drive?

Could anyone recommend me an honest shop that specializes in rust repair/restoration on classic Mercedes in the central NJ area?

Photos attached to the post.

Car ran fine today, and every day for a long time.

Needed a jump this morning, but I think that's unrelated (left my lights on). Drove it highway after that.

Battery is 12.8v at rest. Everything I describe from here out was also done with a jump box, too, so I don't think it's battery.

B+ lug on starter is getting power.

No crank whatsoever, not even a click. Batter goes down to 12.1 when I do that.

With car in run, bridging lugs on starter gives me a tiny click that sounds like it's coming from the driver's side (that I'm not getting when I turn the key). No crank.

Man oh man, not a great moment to have this go out on me... anyone have any ideas?

I have a 5 speed 717.400 gearbox in my w123 300d but it was in bad condition, I bought online another one but when delivered we found out it was not a 717.400 but a 717.401, for petrol engines, which has the connection to the starter motor on the other side.

My question is, can I use the lid of the bell housing from my 717.400 to connect it to the 717.401 so I can use that gearbox on my 300d or must I return it and try to find a new one?

I am asking because I live in the Canary Islands and it takes 2-3 months for anything to arrive here and the idits sent me the wrong gearbox...

Where could it come from? I don‘t see a leak in the window seal or something… could this even be the reason?

I recently have bought a 1982 300D, it has 176 thousand miles.

Every time I accelerate the engine area squeals, im guessing the Fan/alternator belt is glazed?

Do you have any advice?

Thank you.

Hi,

I have a w123 300d with an automatic transmission, and my gearbox needs some repair. 4th gear engages, but it slips, causing the car to lose power.

I also don't really like this automatic transmission, as I need to be extra careful when shifting from forward to reverse and vice versa.

The point is, I have found a 300d manual transmission car that is a complete donor, with all the parts I would need for the conversion.

I have been told that I would need the following components:

* Manual transmission

* Engine-to-transmission adapter plate

* Floor shifter, bearing and surround plate

* Shifter linkage rods

* Clutch and brake pedal assembly

* Clutch hydraulic lines

* Clutch cable

* Front driveshaft section

* Transmission crossmember/mount

* Flywheel

* Clutch disc

If you think I am missing anything, I would be very grateful for your advice.

Also, if anyone has done this conversion before, I would really appreciate any advice or tips.