benz diesel

[8------D]

found a '92 mercedes benz 350sd, 203k auto $8950 asking.

i want it badly :smack:

[IN-FLT]

damn... thing has another 300k to go ! ;)

[jnecr]

that's about $4k too much if you ask me... 203k miles? I don't care how reliable the engine is, other shit will break...

[Vampire Cockroach]

jnecr is right... i saw a mercedes sd with 550k on the odo in the shop once... to get his door handle replaced

[jnecr]

jnecr is right... i saw a mercedes sd with 550k on the odo in the shop once... to get his door handle replaced

haha, that's funny. My grandmother has a '86 300TD or something like that. Never had a problem with the engine, but every-now-and then some gremlins show up and they are a bitch to fix. And.. because it's a MB, it can be kinda expensive.

[8------D]

my dad had a '83 240D with unknown number of km, probably way over half million. this is the S-class benz. i checked around and prices are not dipping below 6k for those 350sd's.

for some reason i have a diesel mania lately. i already built and "purchased" number of diesel jettas from vw.com haha

[jnecr]

well then go for it man. You won't be disappointed by the diesel...

[8------D]

i love diesels, im just weighing so many options

[gerich]

What kind of mileage does that model get? I seem to remember a discussion on ncvw a while back about benz diesels being somewhat less efficient than the current and recent vw diesels. Nice car but I know that the injection pumps for those cars are over 1000$. Those older diesels have some of the strongest bottom ends ever built but can still have expensive repairs. Don't take this as not liking the vehicle but be careful with buying a higher mileage MB.

[jnecr]

What kind of mileage does that model get? I seem to remember a discussion on ncvw a while back about benz diesels being somewhat less efficient than the current and recent vw diesels. Nice car but I know that the injection pumps for those cars are over 1000$. Those older diesels have some of the strongest bottom ends ever built but can still have expensive repairs. Don't take this as not liking the vehicle but be careful with buying a higher mileage MB.


I'm pretty sure that this is a pre-chamber injection diesel. So the mileage won't be outstanding, but it would be better compared to that same model with a gas engine. Although, '94... that could be direct injection. Bojan probably knows if it's DI or IDI. Also, I think there are probably some good power upgrades as these diesels have been around for awhile.

[pinky]

for a 1991

EPA Mileage Estimates: (City/Highway)
Automatic: : 22 mpg / 25 mpg

[wolf_walker]

That's a W140 car with the 3.5L 6cyl diesel, one of the most dreaded/loved sedans MB ever made. The 140 chassis is astoundingly over-enginered and vastly more technical than the W126 it replaced. And while this is great for handling and brakeing and egronomics, etc, etc, etc, it also has a habit of breaking fairly regular and requiring the GNP of a small country to fix the boat. The 6cyl diesel is another story in and of itself, it started as a 3L in about 86 with the 300SDL, and it was known for bad cylinder heads which MB never "officialy" acknowledgedl though they did replace a bunch of them. And when I say bad cylinder head, I mean they didn't get 100K miles when they were new before they were cracked. EVentualy a "fixed" head was made, casting number 14 and higher I *think* it was. Anyway that part does not apply to the 350SD, but the point of the history is it's the first time MB did NOT take care of it's customers, and the majority of us never forgot it.
Now, that motor, once the head was fixed, became the 3.5L you see in the w140 cars. Head was good now, BUT, since they altered the stroke it started wearing the cylinder bores oblong and causing crazy oil usage at VERY low miles, as in like 40K miles in some cases. Yet again, no recall, but it's a very very well documented issue that MB did ocasionaly (try) to fix if a person bitched enough. They were not all affected, you see them ocasionly with 250+K on the original motor, which is how it ought to be, but you see a lot more on the 3rd or 4th at that mileage. Buyer beware, and never buy without COMPLETE service records and deep pockets, just in case.

The moral of the story is, the 87 or so W126 300SDL was about the kats meow of Mercedes diesels (once the head was replaced). The 85 300SD was a good one as well as it got the taller rear gear and higher stall speed converter and better vacuum shift control circuit. The build quality and engenering that made MB famous was still there in those cars, as was the legendary OM617 5cly TD. The transmissions are all finicky, but that's another discussion. Expect 30mpg give or take on the highway for a w126, 25 or so around town. Which was light years better than what there gas engines were doing in the same chassis.

Oh and most importantly, the W140 is ugly. :upyeah:



My rocco gasser get's 33 however :) , but it ain't no MB of course..

[Apex_1.8T]

So Wolf, are you our resident MB diesel expert? I have a 85 300D someone gave my wife last year. I've started working on it. It runs great, turning off the engine is another story. The interior is in great shape, too bad the body isn't. I'm learning alot about the W123's but until I get my hands on a Bently Manual and some $$$, it will be a slow project. Wife said no more $ on the Jetta until I get progress on the MB. She loves this car for some wierd reason and wants to convert it to bio-diesel.

[pinky]

It runs great, turning off the engine is another story.

does it have an electrical fuel pump?

[Apex_1.8T]

I'm pretty sure it's the vacuum shut-off valve. Most everything on this car seems to work thru vacuum lines. The biggest problem is that the vacuum lines are all screwed up, there's two coming out of the firewall that have been cut. One, I think is the EGR line and no clue on the other. There is one line that tees-off and loops around and connects back into the tee. The biggest biggest problem, is that I'm stubbling thru it and slowly learning what part is what. I haven't done any serious auto-mechanic work since 1981! You'd think with an Associate ME Degree, I'd be a whiz at it.

Wife still hasn't gotten the title to it. The previous owner passed away, so I'm hesitant about sinking major $ into it until I have the title. The price was perfect... FREE. I'm sure I'll be posting questions about the MB soon enough.

[wolf_walker]

Apex, sorry I forgot to check this thread.

There is a little tiny vacuum cutoff right on the switch in the clumn, you cand find the two vac hoses going to it. There is a cutoff valve on the injection pump, you'll see how it works if you look at it. Check the valve on the pump with a mityvac and see if it kills the motor, check vacuum to the switch on the column, somewhere in there is your problem. I have a full set of the factory w123 service manuals in the closet somewhere, I can photocopy you stuff and fax it if you need, but there is a LOT of it. Dunno if Bentley makes a manual for them or not, the paper stuff I have is out of print, but available on CD. Used to be able to find it online as well. E-mail me if you need more info.
They are great cars, the w126 is better though.
Expect 25-30mpg, and to need a transmission at some point. :) The vacuum shift firmness control is fun...

If it's rusted, don't bother, there still cheap if you hunt.

[wolf_walker]

85 is the best year though, it had a taller rear diff gear, higher stall speed converter, the best of the none too good transmissions, featuring the blue vacuum modulator dealy that made things work better shift wise, well, more consistant if not better. Few other little things.

Disable the EGR as well, it's junk for a diesel, same problem the TDI VW had.

[jnecr]

Disable the EGR as well, it's junk for a diesel, same problem the TDI VW had.
That's for damn sure. EGRs kill diesels, I hate 'em..

[Apex_1.8T]

Thanks for the offer Wolf. I've since seen some of your posts on Mercedesshop.com forum. I've printed most of the vac diagrams and am hoping to buy a mityvac next weekend. Thanks for the heads on the EGR. I've read the threads regarding disabling it. I'm pretty sure the vac line to the EGR is already disconnected along with the door locks.

I do have one quick question. Do you know anything about Autohaus Arizona (www.autohausaz.com (http://www.autohausaz.com))? They sell the shut-off valve for $20. I've seen it online from $60 - $100 on other sites.

Saw that VW pick-up in your pics. Brought back alot of memories. First vehicle I learned how to drive manual transmission with. Also had fun parking in it when I was dating my first wife. Cramped but ... oh boy! :oddeye-hellyeah:

Thanks for all the help guys. This truely is a great site, lots of friendly dubbers.

[wolf_walker]

Thanks for the offer Wolf. I've since seen some of your posts on Mercedesshop.com forum. I've printed most of the vac diagrams and am hoping to buy a mityvac next weekend. Thanks for the heads on the EGR. I've read the threads regarding disabling it. I'm pretty sure the vac line to the EGR is already disconnected along with the door locks.

I do have one quick question. Do you know anything about Autohaus Arizona (www.autohausaz.com (http://www.autohausaz.com))? They sell the shut-off valve for $20. I've seen it online from $60 - $100 on other sites.

Saw that VW pick-up in your pics. Brought back alot of memories. First vehicle I learned how to drive manual transmission with. Also had fun parking in it when I was dating my first wife. Cramped but ... oh boy! :oddeye-hellyeah:

Thanks for all the help guys. This truely is a great site, lots of friendly dubbers.


I love Autohaus AZ, been buying from them for a long time, good stuff and never a problem.

Yeah, my old pickup, 600K miles worth and starting to look it.
I learned how to drive a stick on that critter too. Love it to death.
Have to do some rust fixing pretty soon.

Mercedesshop is a darn good forum, I posted a ton there.
Some real sharp guys, and a few with questionable automotive morals, but hey.. :)

[wolf_walker]

That's for damn sure. EGRs kill diesels, I hate 'em..

The one on the old 617 motor usually self-deactivates. (read: cloggs solid)
:)

[jnecr]

The one on the old 617 motor usually self-deactivates. (read: cloggs solid)
:)

I wish the TDIs would do that, instead they just clog the intake...

[wolf_walker]

I wish the TDIs would do that, instead they just clog the intake...


Interistingly enough, the concensus on the old merc D community has been that while it looks like crap, an intake full of soot and crud does little to effect performance. I think a guy even ran on a chassis dyno and showed as much. This is within reason of course.

[jnecr]

The one thing that it can do is ruin your turbo. The boost spikes are already bad enough, with a clogged intake they get horrific.

[wolf_walker]

The one thing that it can do is ruin your turbo. The boost spikes are already bad enough, with a clogged intake they get horrific.

I don't think the mercs have this problem, but I'm sure the TDI is a totally differnet animal in that way.
Really there isn't much you CAN do to a 617 to kill it, short of bad overheating or running with one of those $$$ oil cooler lines busted.
They built those SOB's back then, I've never seen there equal for longevity, short of the 1.6 IDI VW of course.. :)
And what's bad is I swear, my 300D felt faster than my 8v gasser rocco does. Granted it was tuned as I could get it, but still.
Rocco get's better MPG though.
That's one thing to remmeber, while the Mercs get good mpg compared to the gas swilling beasts they had in those cars back then, there still not all that great. My Saab 9K and E30 BOTH got better mpg than my 300D did, especialy after diesel prices shot up. Bummer it is..
But on a lonely stretch of black interstate at 3am after driving 12 hours in the dead of winter, there isn't much more comforting than that 5cyl humming away and that huge steering wheel holding your hands.
I ran my 123 from just outside OK city up old route 66 to around St. Louis, down the big river, back on 40 east and got in out here east of Raleigh in one sitting once. Got 32mpg on that North South run down the river too, best I ever saw. That was a hell of a road car.
Ahh, memories.