This one is more of a LERN ME thread so I can get familiar with a car someone bought rather than doing research on a prospective buy. This is a new one for me.
My 19yo nephew has been looking at an interim replacement for his 2004 4Runner with frame issues, and has been looking at all sorts of things. He was focusing on stuff that can loaf down the highway in comfort, as he's commuting back and forth to his girlfriend's place a lot which is about 75mi+ away from home. He stumbled upon a 1995 Mercedes E300 Diesel up the street from his house and bought it relatively cheap. You know, one of these:
(Not his actual car, but the same paint/wheels as his)
Car has 180k miles and looks to be in really decent shape for a New England car (has a few minor rust bubbles and the interior is in good shape). I did some preliminary research and found out the following:
-Last year of the W124 chassis, and the only year that chassis came with the non-turbo OM606 I6 diesel and a 4-speed auto.
-Kinda rare
-I see people saying these are the "last of the good ones" on various sites
Other than that, I know nothing about old Mercedes diesel stuff other than a guy I knew had an older W123 with half a million miles on it, sold the thing, and the guy who bought it tacked on another 250k+ on the thing before the tin worm ate it. That impressed the hell out of me.
My nephew says that the "glow plug module might be faulty" and that "one of the windows won't go down all the way", but other than that, it just needs regular maintenance stuff like fluid changes that you'd do to any used car. He wants to do typical teenager stuff, like wheels and tint, but that's about it.
Even though it's not mine, I'll probably help him turn wrenches on it now and then. Where's a good place to start to find parts? I want to point him in the right direction as he starts going through everything.
For parts, AutohausAZ has a lot of MB stuff that's somewhat hard to find elsewhere. Other MB-centric (ish) places worth checking are FCPEuro and Pelican Parts. I still get plenty of stuff for my W124 off RockAuto. And believe it or not, sometimes the various actual MB dealers have good prices online.
A '95 will have been built originally w/ a biodegradable wiring harness. Yes, you read that right. The engine harness is the issue, as the heat seems to be what accelerates its decline. Most will tell you that a car with 180k must have already had it replaced. I can tell you that's not necessarily the case - mine made it to 220k w/ the original. When I removed it, the insulation basically shattered and what was left was a harness of bare copper strands. A replacement harness should have a tag up near the computer connector that will have a date on it like 2008 or '12 or something. Not '95.
I don't know much about the diesels. The W124 are incredibly solid. A friend of mine had a diesel, might have been a '95. It was indeed solid, but boy was it slow. Although not as slow as his W123 diesel.
Tk8398
HalfDork
7/7/21 3:37 p.m.
The transmissions in those don't seem to hold up too well, and om606 glow plugs can be a major issue to change (they get stuck and snap off), but otherwise if the rust isn't too bad it should be pretty good.
Good info so far. I was afraid that this would have the biodegradable harness, and I did warn him once he started zeroing in on 90's Mercs, but I'm hoping this one has had it replaced. I'll have him look for the tag.
And yes, he's not looking for speed. He's certainly not going to find it here! He's looking for a comfortable cruiser that can loaf down the highway, and this should do that just fine.
Glad he's not looking for speed. The om606.910 doesn't really make any power. But if he wants to go slowly in style for ever, then he made the right choice.
One nice thing is that most brake/suspension parts are available cheap from RockAuto.
I used to be a benz guy. A friend just purchased a w124 to rehab. They're very much an "old man" car without a lot of aftermarket support...but maybe they are having a moment with kids an hipsters?
-Don't buy the "last of the good ones" argument. People say that about every generation.
-Don't compare it to the w123-the w124 was always less reliable and more complex. A large portion of failures on the car will be electrical, but not electronic. IOW, passive components, solder connections, etc will go bad, but there arn't many computers involved.
-Parts are still expensive (at least compared to what I deal with in honda-land)
-The factory manual is bad. Like, remarkably so. Get manuals from other publishers (haynes, Bently I think?)
Good luck!
In reply to CrustyRedXpress :
Yeah, I rarely take the "last of the good ones" argument as fact. Any enthusiast will say that about any car they like. 
My nephew is handy with a wrench (honestly, he's probably better than I am at this point) and works at a shop, so he has access to pretty much anything he needs tool and research-wise to fix the car. He's done some major repairs on his 4Runner by himself that have impressed the hell out of me, especially since he's still a teenager.
He told me that he "needs to get German car ownership out of his system early" which was the main reason he got this. His basic plans are tasteful wheels, tint, and a stereo upgrade. You know, teenager stuff. I just informed him of what Radwood is, and he's digging that. This car is a dead ringer for that crowd.
Rock Auto has a lot of stuff for these and has been a great resource for my W126. But yeah, FCP Euro and Pelican are also good resources.
I'm definitely more familiar with the OM603, but I'm sure the OM606 will serve him well. Glow plug module can probably be found for cheapish on eBay or forums. Honestly forums are a handy asset for these Merc diesels.
In reply to Tony Sestito :
Well, if he's mechanically inclined and can use the shop's parts account it could be a really good fit! They probably also have an all-data subscription or similar.
Tell him to post it here if he pulls the trigger.
The OM606 doesn't make much power in stock form, but it's pretty easy to see 35+ mpg.
With an (expensive) modified injector pump and a turbo, however, those things can make serious HP, and the bottom end can usually take 750 or more hp.
Long video, but very informative. This is an OM606 in a Mopar making 680hp and almost 1000 lb-ft to the rear wheels.
I had an OM606 in a W210 (99 E300). For me, W210 is the last of the iron-tank reliable Mercs, and the W124 is even better in many ways. My W210 went 240k IIRC with next to no failures. Toward the end it needed a radiator, but that was because my ex kept bumping curbs with the front lip. The first thing you hit is the lower radiator support which was made from stamped steel. It would push the radiator back into the fan blades. Not sure if the W124 is the same, but my fix was to weld a couple struts from the cheap radiator support back to the crossmember.
Well, the fix was actually to sell the car and divorce the wife who kept berkeleying it up, but that's a different story.
You'll find that Mercedes liked to operate as many things as possible with vacuum, including power locks and a large number of air blend doors in the AC. A bad check valve or a leak in a hose can require a complete dash disassembly to fix. The one thing that would have been nice if it were vacuum operated... wasn't. It likely has what is called a duovalve (expensive) which is a twin valve responsible for shutting off the hot water to the heater core. It fails and you get intermittent hot air when you don't want it. It always puzzled me why Mercedes would take an engine that makes zero intake vacuum, then add a vacuum pump just so they could make everything operate on vacuum.
Otherwise, mine was darn near bulletproof. Toward the end I had a vacuum leak. If you let it sit for 3 days, you couldn't unlock the doors. Fortunately the key fob had a function where you could hold the unlock button and it would roll down the windows. The interior at 240k looked better than a Chevy rolling off the lot. The seats were brilliant. The leather was super-high quality. The dashboard had zero rattles or buzzes. The engine couldn't really be heard in the cockpit. The carpet still cleaned up like new. It was such a tank that after my wife got T-boned in it, I didn't hesitate to have the body shop weld on a complete right side from LKQ to fix it.
And how does Mercedes make them handle so spryly and still ride like a 1974 Cadillac?
I'm sure there are lemons, but the W124 is a great platform. My BIL has a gas version and loves it. I think he's pushing 200k on his.
Our friends at FCP Euro should have parts, too.
