Before you take the door handles off, try some graphite, liquid is best, I know I've posted the MoPar/Jeep stuff I recommend most, the can isn't here, perhaps someone will post the P/N ~ a $7 can lasts for close to a decade including many vehicles and the house, etc., etc.....

The fuel and oil leaks will beat up everything rubber / plastic under the hood so take some time to properly clean it then keep after it ~ I was outside before sunup this moring de greasing my 300CD's engine in the 43* F chill.... .

I want to try and wash and wax it to - morrow so the engine shampoo always comes the day before .

Keeping it clean also means you won't mine working on it as much and $ave$ you $ .

If the engine doesn't reach 80* F you're going to loose power and fuel economy so DO NOT ADJUST THE THROTTLE LINKAGES until eveything else is done and it starts and runs *perfectly* .

The throttle rods cannot go out of adjustment .

Get cracking and test those glow plugs properly as has been detailed here several times ~ you have to do things in the correct order else you'll never stop chasing your tail .

Everyone who's never been to any Desert thinks it's hot always, boy howdy are they wrong ! .

I feel for you, L.V. in Winter can be miserable, more so sans heat .I just replaced my thermostat Tuesday and wow ! more power, fuel economy jumped from 22 > 29 MPG, this included some fair bit of 85 ~ 90 MPH open road driving where the fuel economy normally drops off over 65 MPH so I'm well pleased and the heater is back to working great again, @ 43* F cold start I have heat in three blocks .

The engine's heat is steady @ 84* C, slightly warmer than I'd like but Diesels thrive on heat, lots and lots of it for maximum efficiency .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Will this be of help .

Will this be of help . Sorry no picture .

Update time guys! Sorry it took so long, work has been very very hectic.

First of all, I replaced many of the vacuum lines. Most of them looked very old and I was really worried they would break on me or may develop leaks soon. Also, many were cut down to shorter lengths due to the previous owners attempt at routing the vacuum lines... I went with a very simple approach. The line you see me using is this stuff.

First of all, I removed all non-essential systems from the system such as cruise control and my locks.

As you can see they are connected to a 4 way connector, but that connector is not connected to the system. It is the simplest way I found to eliminate it. If you need to do this for diagnoses purposes using a golf tee (as previously mentioned) would work well.

On the main vacuum line I have 2 T connectors. To one I connected the 3/2 valve as shown

Then I connected the 3/2 valve to the VCV with a Y connector, one end connected to the 3/2 valve the other to the transmission. It seems to be how it is depicted on most vacuum diagrams and seems to work wonders.

The other T connector on the main line I ran to another Y connector, one side going to my ignition switch so the car shuts off. To figure out which line was used to shut off the car I simply started it and hooked my brake bleeder to each line and tested it until the car shut off. This weird thing is connected to the other side of that Y connector.

No idea what it is, but it was connected and I figured I should connect it back. Any ideas? Maybe it's the cruise control system or something. If it is, it doesn't appear to be working.

The end result is this

Also the weird lighting on some of these photos (all except the 3rd photo actually) is because I took them at night using a magnetic flashlight I bought from harbor freight for about $8. It works wonders, especially since my complex doesn't technically allow people to work on their cars.. So all this was done after dark, when the office was closed.

I also re-keyed my lock cylinder for the driver door, but forgot to take pics of the process. I'll make a post in this thread going step by step through the process for anyone that needs it in the future. Its surprisingly simple. My work around for the driver door lock cylinder being broken was to swap the entire door handle assembly, they're interchangeable for anyone that needs a door handle, you can pull one off a driver door or vise versa to replace a broken one

In theory you could probably take a back door handle and swap it with the passenger door so you only have one lock instead of two. This appears to cause some trouble though, as my passenger door will no longer stay unlocked. It has to be manually opened from the inside. I had to leave the rod that runs to the lock itself detached since the cylinder was broken off at the pin, so I believe this is what is causing the issue.

Anyway, the transmission shifts (mostly) okay now. I haven't replaced the line from the transmission to the VCV yet, that is next on the list. It's just been cold and rainy (and it snowed last week!) so I haven't crawled under to swap the lines. I will likely do it this week and see if that helps or fixes the remaining issue.

My remaining issue I refer to is that when the car shifts down it doesn't like to shift back up unless I come to a complete stop. My temporary fix is to just shift the car to S, at which point it shifts normally again. Another issue is I think my linkage needs adjusted, It feels very loose shifting between S and D, like somethings come loose. Something i'll have to check when I crawl under again.

Also, I replaced the injector return lines as well. I'm not totally sure I ordered the right size as they seem to be REALLY hard to get on, but it's surely better than what was on there before. Several of the lines snapped in half as I took them off, and I actually had to the ends off two of them because they snapped at the nipple. Was a giant pain. The line furthest back I didn't replace yet, the throttle linkage is in the way so i'll have to unbolt all that to get it off and replaced. Also on the injector furthest back there is one that is capped off, is that how it is supposed to be or is something wrong?

Anyway, I'll be sure to update you guys soon as I take pictures of that lock cylinder and I can show the process I used to re-key my door lock!

__________________
1981 Mercedes 240D - Automatic transmission

That is the cruise control.
I have removed it from my car.

- Peter.

__________________
2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S

Thanks! I enjoy taking long drives, so I will have to figure out how to connect it properly and get it working okay, but that can wait.

I forget to mention that my car rarely goes over the 100 mark, and when it does it stays below 175... And that takes well over half an hour of driving. Doesn't sound to bad, but due to that my heater doesn't blow warm air until I drive for over half a hour which really sucks the past couple days.

I have a feeling the thermostat is hung open, I plan to do a radiator flush/change soon so when I do that i'll just throw in a new thermostat. I'll have to look at the manual and find out how much coolant this car takes. And an oil change is on the list of things to do soon as well.

Also, do these vehicles have a transmission filter? If so I may change the fluid and filter in the transmission just to be safe. The fluid looks okay, as in recently replaced, but I know from experience that if the filter wasn't changed then that is pretty useless to do.

__________________
1981 Mercedes 240D - Automatic transmission

The fuel return hoses are supposed to be really hard to install, I use a nice pair of duck bill pliers, some prefer needle nose pliers, don't buy the cheapy H.F. ones, buy the nice ones that have suffienent pressure to grip the hose well .

You don't need to tough the throttle linkage to do that last short hose with the 'bullet' in it, just some practice .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Thanks! I used a pair of cheap needle nose pliers, probably why it was so difficult. I think i'll run over to Home Depot (It's literally in the parking lot next to my apartment) and grab a decent pair of duck bill pliers. I think they'll work better, my needle nose pliers kept slipping off. Such a pain. The hose i'm talking about connected the 3rd and 4th injector together, it's right next to the valve cover and directly under the linkage. I'll see if I can finesse my way to it and swap it out later today.

Also, my speedometer is reading 15 mph slow... It's a fun guessing game when I'm driving Not really, I downloaded a speedometer app on my phone and I've been using that.

__________________
1981 Mercedes 240D - Automatic transmission

Buy a nice pair of good quality dykes too and again : avoid those cute little delicate ones and also the super long ones, what you need are sturdy Mechanic's tools .

Look at that linkage bracket ~ there's a notch in the bottom of it, that one bit of hose is supposed to be longer and after you've connected it to the # 3 & 4 injectors, you tuck the excess hose into that notch ~ the hose goes under, not over like the rest of them .

Take some time and look at old posted photos, you'll see it and say ' ah, HA !' .

Remember : this is a fairly simple car , engineering driven so if something seems impossible, look for a different approach or simpler answer, here or just ASK the only 'stupid' question is the one you don't ask .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Get to that flush and new thermostat ASAP ! Diesels are compression ignition meaning they need heat to operate properly, if you don't have some heat out the vents in three blocks, it's running too cold .

Not like gasoline engines in this .

Your power and fuel economy will improve markedly as soon as you replace the 'stat, you're very wise to want to flush it properly .

Making the correct power will help the shifting too because you'll have more power with less throttle....

Right now, go open the radiator and look down inside with a good flashlight ~ in addition to reddish or brown coolant being bad, there's usually crusty looking stuff accumulating on the open ends of the tubes you see ~ that's called 'Solder Bloom' and it's very bad, is clogging the entire cooling system and killing your engine .

When flushing, always have both heater valves on full and you'll need to _drive_ the car a ways, not just idle it in the parking lot .

1/2 way down the right side of the engine is a 17MM hex plug, it's fairly behind the exhaust's down pipe and you *must* remove it to properly drain the old coolant out, I use a 3/8" drive 6 point socket and a 6" extension, the plug has a washer that will fall so don't work over gravel/mud/grass/etc. .

Try to buy the proper 82* C thermostat, you'll need the special O-Ring too to make sure it's in the box -before- you begin to take things apart .

A tiny bit of white lithium grease on the 6MM (10MM ATF) bolts threads before re installation will help avoid problems later on .

This is messy oily, hot work but simple and easy, you won't get scalded by the hot water coming out when you remove that block plug .

Try to set up a working area wth a hose or several gallons of distilled water before you begin and be aware the old coolant, if rusty, will stain concrete badly so be cautious where you work .

Man take an hour long drive to the truck stop and do the flushing there as the concrete is already nasty....

This will pay big dividends this Summer when you're able to Motor merrily along in blistering heat with the car running fine....

Yes, there's a filter in the tranny, there's also a 5MM drain plug in the torque converter, draining both is very wise but needs a LARGE drain pan and two gallons or so of the correct ATF, before you begin .

I bet you love apartment living about now, huh ? .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Haha, I have always hated apartment living

As for the draining and replacing, luckily Las Vegas has tons of empty gravel lots where I could easily do the fluid changes, and that is my current plan. I'll buy a large pan to drain everything into before I do the changes, and i'll be sure to grab the correct thermostat. I plan to buy 10 or so gallons of distilled water and run that through the system as a way to flush the system. I think that should be plenty to do it properly. It's not my first time flushing a radiator in this fashion, it's more of a hassle than using a garden hose but uh well.

I'll drain and replace the filter on the tranny, since i'm not so sure the previous owner replaced the filter. I'm likely going to to do a oil change and fuel filter change at the same time, so i'll have to order all of that stuff soon.

__________________
1981 Mercedes 240D - Automatic transmission

Good ~ forge boldly ahead where evryone else has gone before .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Correct. The last pigtail of the fuel lines is short and has a plug in it. If the lines do not look wet, they are OK.

Me too. But I've never owned a Mercedes with working cruise. When I removed that contraption from mine I tested it with the Mity vac and it seems to be working. That is the plunger is activated by pumping on the mity so my guess is that the problem is in the "brain" which I also removed. It's under the dash on the plastic knee guard to the left of the steering column. I would like to fix it but in my case there is no longer any point as the car is now a backup/winter/town driver for me. Not only am I not likely to fix the cruise I'm about to remove all A/C components from the engine bay so I can get easier access to other things I need to.

Your car is likely in better condition than mine. Least ways I hope so so you might bennefit from getting the cruise working.

- Peter.

__________________
2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S