thinking of buying,Need help.

[Freight_Train]

Found a 1983 300SD at a car lot here in town.shows 270K miles.They want $2650 financed(wish I had cash could get it much less).Body is dang near perfect!Interior looks pretty decent.Drivers seat has some rips in the leather.Some of the wood trim is broken on the dash,Dash pad is cracked,passenger seat and rear seat is in good shape.Under the hood the CDR in the air cleaner is missing but the hose and rubber is still there( ),2 broken vaccumn lines at the front of the engine(I think they are Vaccumn lines,one might be a boost since it looks like it comes from a waste gate thingy) that connect to a box on top of the Cam/valve cover.Going for a test drive today(Tues).I would love to have a good car to drive back and forth to work especially if it runs on Oil.This household is nearly all oil burners.Now if I could get my Tuner cousin and my grandmother in a diesel we wouldn't have to go to gas stations any more.BIO DIESEL!!!!

 

[towcat]

sounds like the interior has seen some sun damage. my suggestion is to find a local benz shop and have them take a look over it for the mechanical side. keep in mind when something breaks on these cars, you will consider working on your IDI "cheap" compared to the prices you will pay for the parts. Biggest thing that bothers me is the "broken" vaccumn lines. If the box you are talking about that is mounted on the valve cover, and has throttle linkage affiliated with it, that is part of your cruise control. Kinda nice to have on long trips. Mime's not working on my '87 and its the computer brain that went kaput. $600 for a replacement It just provides me a easy excuse for breaking out my '92CC

 

[Full Monte]

Hello Freight,

I'm not sure I would jump at that deal. I bought an '87 300D recently after looking for the right "deal" for over a year. What worries me about your deal is that because you have found some "minor" problems with it, what "major" problems haven't you found? Mercedes parts aren't cheap. Your model has the 5 cyl engine, which has a reputation for a bullet-proof engine. The cast iron head is really great, too. Also, take a look at prices on craigslist. If there aren't many ads in your area, look in other areas. Good luck!

 

[Freight_Train]

well,The hunt continues.Thing ran pretty good(other than being slower than an overloaded Kenworth).Nothing worked....rear windows,passenger window(driver side did!?),front to rear passenger power seat(side shift and up and down did!),Tach was dead,No radio.
now the good
Didn't smoke,turbo worked great,about half way though the RPM range it kicked in and car gained major power(and could hear it too!SWEET,Sounded like the Enterprise!),Glow plugs worked,Driver side window worked,uhhh,horn and starter worked.....thats abuot all I could find that worked.Oh tranny,engine,brakes but that is about it.$1000 car maybe

 

[The Warden]

Do you by chance have any pictures?

The wood "cracks" are actually normally just cracks in the finish...this isn't a certainty, but it's a fair bet that the wood itself is okay. The finish CAN be redone...take a look here (came from this site). If the interior's in good shape other than that and the crack in the dash, and if the body's happy, that may actually be a fair price, although it seems a bit high based on the mileage.

Any chance of doing a compression check? It'd be nice to see how healthy the engine is...also be good to find out when the last time the valves were adjusted, if the timing chain's been replaced (if so, how long ago, and if not, how much stretch was there the last time the valves were adjusted?), etc... Regarding a CDR, there isn't really a valve/diapharam per se like we see on our IDI's, at least not in my experience. On my car, the hose comes off the valve cover and into the air cleaner...where the crankcase gases go into what's supposed to be an oil separator (but doesn't really work). Theoretically, the oil is supposed to go down a metal tube back into the crankcase (the tube fits into a nipple in the bottom of the air cleaner assembly, goes around the turbo, and into the engine down by the oil pan), and the gases are supposed to go back into the intake. Earlier turbo 617's handled things differently, with a hose going straight from the valve cover to the bottom of the engine block, with a T-connection going to the air cleaner.

I could be mistaken (my '85 doesn't have this box), but I BELIEVE that the black box on top of the valve cover is part of the transmission modulation setup. The cruise control actuator (that physically moves the throttle linkage) is actually the forward-most part of the throttle linkage, with the box just behind the power steering pump (take a look here for a picture of what it looks like minus the arm that the linkage attaches to). With vacuum leaks around the tranny modulator, you'll wind up with hard shifts and may think that the tranny's on its way out...there have been numerous people who've condemned a tranny due solely to vacuum issues.

BTW, there IS a boost hose that goes from the intake manifold to a diapharam (called the ALDA for reasons I don't know) near the back of the injector pump. Boost pressure pushes on the diapharam, that in turn increases fuel output accordingly. The line goes through an electric valve that is connected to a sensor in the intake manifold; if the sensor sees boost pressure being too high (above about 15 psi), it'll dump the boost signal going to the ALDA into the atmosphere, in an effort to prevent an overboost condition. I don't know of any boost lines coming from the wastegate itself, though...but, that doesn't necessarily mean anything.

Just some thoughts...good luck! Also, make sure you do a thorough job of inspecting the suspension...that's the single biggest mistake I made with my 300D, and I really regret it now. If I put the $$ into repairing the suspension on my car, I would be in more than she's worth in my eyes...but, other than that, my 300D has actually been very easy on my wallet. She's, hands-down, the most economical vehicle I've ever owned...parts can be expensive if you need them in a hurry, but there are places online where you can get them at reasonable costs (such as www.mercedesshop.com; click on "Fastlane", and www.performanceproducts.com) and even local suppliers if you're careful (for instance, I replaced my axleshaft/CV joint assemblies for $60 per side for parts, with a lifetime warranty), and if you can do your own work, you're set.

 

[The Warden]

well,The hunt continues.Thing ran pretty good(other than being slower than an overloaded Kenworth).Nothing worked....rear windows,passenger window(driver side did!?),front to rear passenger power seat(side shift and up and down did!),Tach was dead,No radio.
now the good
Didn't smoke,turbo worked great,about half way though the RPM range it kicked in and car gained major power(and could hear it too!SWEET,Sounded like the Enterprise!),Glow plugs worked,Driver side window worked,uhhh,horn and starter worked.....thats abuot all I could find that worked.Oh tranny,engine,brakes but that is about it.$1000 car maybe

Figures; I was just starting to type up my first post when you put this in...

Regarding the windows, did you check the fuses? The power windows on these cars are fused (unlike the circuit breaker you see on an IDI), and are fused in a weird way. The driver's front window and the passenger's rear window are on one circuit, while the passenger's front window and the driver's rear window are on a second circuit. If the motors weren't making any noise at all, that's something to consider...OTOH, if you heard a thumping noise when pushing the button to raise the window, the windo regulator's toast, and that can be some serious $$.

As to power...that might have been an issue with the valves, or may have been a blocked-up exhaust. These cars are sensitive to soot buildup in the exhaust, and this is exacerbated by people driving them with a light foot. The best way to clear up the exhaust is to drive with a binary throttle for a few miles...you're likely to see a giant puff of black smoke, and all of a sudden, the car will be running better and acting more peppy. The OM617 was built to be driven by European cab-drivers, so it's pretty hard to abuse the engine in a way where the engine won't like it...as long as she's maintained properly. Regular full-throttle accelerations are practically expected. Another thing I found is that the throttle linkage may not be adjusted properly. When I got my car, she seemed a bit lethargic...I later took a look at the throttle linkage, and the fuel lever on the injector pump had about 1/8" of travel before hitting the forward stop with the throttle pushed to the kickdown switch on the floor. I adjusted the linkage to get full travel out of the fuel lever, and it was like I had bought a different car...the power difference was simply incredible. Of course, once the turbo kicks in, it's a whole different ballgame...on my car, the turbo kicks in generally between 2000 and 2500 RPM (with the engine hitting th egovernor at 4500+ rpm ).

Power seats...did you hear the motor turning? I've never dealt with power seats myself, but I know someone who has an '87 300D who told me that the motors on the seats are almost overkill but whatever they're driving is made of cheap plastic and tends to break, and that it's actually a fairly easy repair. The switch itself could also be gunked up.

The dead tach was probably just a tach amp not making a proper connection. Take a look here to see what the tach amp looks like...it's essentially a plug, located on the driver's side inner fender. The plug sits within a plastic shell, and the shell's supposed to push on the plug when it's screwed in to the connector. You can CAREFULLY pull the plug out of the plastic shell, and stuff a small amount of cotton in the bottom of the shell (for a less severe problem, a cigarette filter works perfectly). Just that little bit of extra pressure is typically enough to get the tach amp to make a proper connection, and the tach will all of a sudden start working.

Certainly, with the issues you found, the people selling the car are nuts to think that they can get $2500+ for it...but, if you could talk them down to $1K to $1500 (maybe), she actually sounds like a good deal...

 

[towcat]

warden-
if the car needs that much work before leaving a used car lot. he needs to run far away from the car. there's a reason why the lot isn't fixing the stuff.

 

[The Warden]

warden-
if the car needs that much work before leaving a used car lot. he needs to run far away from the car. there's a reason why the lot isn't fixing the stuff.

Point...I'm used to dealing with private sellers who often don't know what they're doing.

OTOH, the info's still there for someone else who may have use for it...right?

 

[pafixitman]

towcat,
Remember, there is an a$$ for every seat!

Having toyed w/ the oil burning MB idea, I appreciate the info. I have noticed many Benz' with inop power windows etc.

 

[Freight_Train]

Hope I can find a decent one before the July 4th rally in chattanooga(The Ford IDI weekend thingy).Reason I was looking is everywhere I turn I heard you CANNOT kill the dang things.Suckers will out live a Cummins driven by Granny!Plus,I want a gas free home so when I fire up the Still,I won't ever have to hit a gas station except for munchies and smokes!

 

[The Warden]

Reason I was looking is everywhere I turn I heard you CANNOT kill the dang things.Suckers will out live a Cummins driven by Granny!

Sounds about right I've got 277K on my odometer (about 54K miles since I bought her in July '02)...the front suspension needs to be rebuilt, there's body damage (thanks loving g/f ), and the interior's thrashed, but the engine, tranny, etc run like new.

I'll admit that I want my next DD to be a TDI, but that's mainly due to the fact that it's hard to argue with 50mpg (and I like getting hybrid owners' goats )...these M-B's are about as indestructible as it gets, and I'd recommend one to anyone who likes to tinker on cars and is looking for something that's reliable and relatively cheap to own. I'd love to get my hands on a cherry 126 or a 123 wagon someday...

Note that "cheap" isn't a given...it depends on what you want. If you get a car with a non-op ACC unit and no cruise control and want EVERYTHING to work, things can get real expensive real quick...but, if your primary goal is to just keep the car running and safe and you start with a car that's in decent shape to begin with, it can be done on the cheap. INCLUDING FUEL, my car has cost me $.10/mile to operate over the 3 years I've had her...less than $800 put into her for maintenance, and that includes replacing both axleshafts, all of the hardware for both front wheel bearing sets, and brakes on all four corners. To me, that's pretty good (certainly less than I've put into anything else I've owned)

 

[towcat]

never say indestructable guys.....I've towed quite a few that died a hard death due to the lack of maintence. many were hand-me-down cars to kids who drove them into the ground. Also, the newer aluminum head cars have gobs more hamster power compared to the older brothers at the cost of poorly designed heads that cost a fortune to redo. "full monte" lucked into a "E" series that got the updated heads, that doesn't happen too often. Kinda ironic, SCA's are a huge issue with IDI's and MBZ with alu heads BTW....the granny's aren't driving slow in the older models, the throttle is actually pinned to the floor, the hamsters are just overworked.

 

[The Warden]

never say indestructable guys.....I've towed quite a few that died a hard death due to the lack of maintence. <snip> Also, the newer aluminum head cars have gobs more hamster power compared to the older brothers at the cost of poorly designed heads that cost a fortune to redo.

Sorry; my mistake...I thought that went without saying. Without proper PM, you can kill ANYTHING in fairly short order...be it an IDI, an M-B, a Cummins, or even a Japanese g@$$er that so many people firmly believe will live forever. Actually, it seems to me that the biggest thing to be careful with on an OM61x engine is the oil cooler hoses...if one blows and you aren't watching the oil pressure gauge, you can lose an engine in a hurry, and there ARE warning signs (particularly oil seepage at fittings on the hose assembly where rubber meets metal). An uncle of mine had a 300D that he killed the engine on because of this...

And, at least in my statement, I was refering to the OM61x engines...I've driven an OM603 and was very impressed with the power, but don't particularly want to play Russian Roulette with cylinder heads...