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Old 09-28-2003, 08:29 PM
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Hello to all !!!

I've always liked the 80's Mercedes. So I started researching them. After reading about WVO, I just fell in love with the idea of a diesel. So I've started looking for a 83-85 300D.

I currently own a 97 Saturn SL2 and a 68 Ford Bronco. Right now I am doing body work on the Bronco. The MB will replace my Saturn as a DD. I am looking for something that is "luxurious," dependable, gets good gas milage, and has class.

I work on all my vehicles, including my two jetskis, but I'm not looking for another major project. From what I've read hear, I should be able to get a very good condition 83-85 300D for around $5k.

I am some what disappointed and the lack of resources on the Web. There are some great sites for Broncos. But then I found that there were only 75k or so 83-85 300d world wide (I think) compare to the 220k 66-77 Broncos made and the vast majority of them sold in the US.

Newbie Questions:

1) What should I look for when buying an 83-85 300D? I know about rust in the wheel wells and the rear bottom fendors. I usally like to check the compression. What pressure should I be looking for?

2) I have found some parts sites, but none are MB exlusive and they all seem to be OEM replacements, mostly just engine and electrical. For my Bronco, I find many sites that make custom parts at good prices. Just as an example, I can't find a place the sells new leather seat covers or any of the interior trim pieces. Can some one point me to some sites?

3) I test drove a 300 SD today. I mistakenly read the ad for it. Although I'm leaning toward the 300D, I had not ruled out the SD. The SD jerked when shifting. The owner said he had it looked at and was told it wasn't fixable. Is this so and is this same problem present in the 300D?

4) I have found some, but can some one give me some good WVO links?

Thanx for reading my long post!!

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Old 09-28-2003, 08:55 PM
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Location: Lakeland, FL
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I can comment on question 3: a diesel Mercedes of this era will not shift like your Saturn or Bronco. There may or may not be something wrong the SD you drove but my 300 D has a different shift from my 500 SEL. Test drive some other cars and you’ll see what I mean. A more knowledgeable member of this forum could explain it better than I but I had to ‘relearn’ to drive driving a Mercedes diesel. There may not be anything ‘unable’ to fix; the owner may not be familiar with how these cars shift. Hope to welcome you soon as a new Mercedes diesel owner.
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Old 09-28-2003, 09:33 PM
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1) Compression pressure on a Diesel is very high (compression ignition). If you want a Turbo model, the normal reading is 24 to 30 bar (1 bar equals about 15psi), Min reading is 15 bar, and max pressure difference between highest and lowest reading is 3 bar.
Readings for a naturally aspirated model is the same, EXCEPT normal reading is 22 to 24 bar. These are the readings you should get on a warmed up engine. It's a liitle more work to do a compression test on a diesel, normally I would check in the injector hole, but you need to replace injector seals if you do, You can also check through the glow plug hole, but it's a shame to pull the glow plugs without replacing them.
2) Use this site (Fastlane) or Benzbin I hear is another. If you hang out long enough you'll hear of different resources for parts. MB parts are generally more expensive than Ford parts, OK? And not alot of "custom" parts either. You won't generally find resources for a chrome differential cover for a 300D, it's usually not considered "that" kind of car. To find performance parts for a MB usually takes alot of hunting and cash.
3) You can still get a jerk when shifting with one of these. A site like this can help you figure it out, although it IS true MB's shift a little "firmer" than many other makes. A firmer shift means less slippage when shifting which means less transmission wear. "However" there is kind of a common problem on these diesel trannies. They use essentially the same tranny as a MB gas engine car, and do a little vacuum magic to "fool" the transmission into working the same as if it were in a gas engine vehicle. The engine has a vacuum pump, mainly to run the power brake booster, but also as you'll eventually find out if you buy one, to run things like the power door locks and, like most other cars of this era, to run the climate control. Well, on a gas engine car, the engine vacuum is also used to run a part on the tranny called the vacuum modulator, which controls how hard or soft the transmission shifts according to how hard the engine is being accelerated. Low vacuum means the engine is being accelerated hard, which means the transmission should be shifted hard to avoid slippage. High vacuum means the engine is being accelerated very slowly (high economy), which will give a soft, easy shift, more comfortable feeling.
What can happen is that you can either A)develop vacuum leaks, B)heve some misadjustment done, C) have a worn vacuum pump, or D)get a restriction in the vacuum line which supplies vacuum to the transmission (the brake booster line), any one of which can lead to low or no vacuum to the vacuum modulator, which more or less makes the tranny "think" the engine is being accelerated hard, and will give, as they would say on a football field, "unneccesary roughness". (Boy, long ways to go for such a lousy punchline). But any of these could be what's going on. It's not the end of the world, it certainly is repairable in competent hands, I've seen this alot.
4) No (hey, a short answer for once!)


PS You can't use a compression gauge for a gas engine on a Diesel, you'll ruin it, the pressure is too high!
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Old 09-28-2003, 10:33 PM
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Thanx for the replies!!

1) I was wondering if the gauge would even work. I will probably get it checked out by a mechanice anyway.

2) That helps. I know parts a lot more. An alt for my saturn or bronco was only about $35, whereas for a MB I'm seeing prices for $135. Yikes! I hope these are better parts then AC delco or Motorcraft!

3) That might be a no go for me. Both of my other vehicles are sticks so if I'm going to go with an auto, it gotta have smooth shifting. How common are manual 300D's? I'm familar with vacuum systems, the Bronco has vacuum wipers.

Thanx again!!

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Old 09-28-2003, 11:03 PM
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Manual 300D's don't exist unless they are a European Model, meaning they were imported here from Europe. You'll have an eaiser time finding a 240D with a manual transmission, though its not a 300D like you're interested in.
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Old 09-29-2003, 04:57 PM
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Join Date: Mar 2003
Location: En te l'eau Rant
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Originally posted by Nuke
An alt for my saturn or bronco was only about $35, whereas for a MB I'm seeing prices for $135. Yikes!
You rarely if ever ever need a new alternator. The voltage regulator (which includes new brushes) can be replaced for under $35.00. And, the truly frugal sometimes replace only the brushes (the part that generally fails) for less than $5 (I think they may be even cheaper that that).
Never a dull moment at Berry Hill Farm.
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Old 09-29-2003, 08:39 PM
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Location: Evansville WI
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I'm familar with vacuum systems, the Bronco has vacuum wipers.
The vacuum systems on these diesels get quite a bit more complicated than a vacuum wiper system. With the vacuum wipers, you have a vacuum source, which is a running engine, hoses to the wiper switch and out to the motors.
These things have vacuum lines running all over the place, a storage tank, and when you shut the car off, at least several days later you're supposed to be able to go out to the car, and turning the key in the lock is supposed to unlock all the doors, the fuel tank flap, and the trunk, all using vacuum. It also uses vacuum to shut off the engine. And remember diesels produce no useable vacuum, so this is all quite a trick. There are plastic vacuum lines running under the carpet in the interior, into all the doors and back into the trunk.

To say you are familiar with vacuum systems because you have a Bronco with vacuum wipers, when compared to these cars, is saying you are familiar with operating a train because you've crossed several sets of railroad tracks. No slam intended, these are quite complex, even in the early 80's.

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Old 09-29-2003, 08:44 PM
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Ahhh, sorry. I was just joking. I did realize the vacuum systems were much more complex.

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