Hello All,

I am relatively new to the MBZ/Porsche scene but have been a vintage BMW guy myself. I just acquired a new to me 1968 200D!

It may not look the prettiest but it is fairly complete and rust free!

Just a couple questions...

1. Does this car supposed to smoke black heavily in the higher rev ranges and while heavily accelerating?

2. I feel like the car idles high, do they all seem like that or, do I need to adjust the idle somehow?

3. Anything I should look out for or do to make sure the car runs smoothly as can be?

Thanks!

EDIT:

One more thing ... Why does it feel like the heater is constantly on. I checked the heater valves and they look like this (Driver, Passenger) / \ or, are they supposed to be inwards to be closed like: \ /

Sorry if my crude diagram isnt the best.

1: No, it is old and likely running rich to compensate for some other problem. It may also have been neglected by prior owners. Have the injection pump calibrated and the injectors rebuilt and it will run much cleaner and more powerfully, too.

2: Idle is usually set after making sure all is well with the injection pump, calibration, and the injectors rebuilt...then it should stay good for a loooong time. Idle is a function of fuel delivery. Everything with a diesel pretty much is, actually.

3: Look out for prior owners who drive a diesel primarily to be cheap or get "free fuel". They typically tend to skimp on every other form of regular maintenance, too, and get away with it since the 123 is such a tank. I will generalize the ones I see around here: a dirty W123 300TD, with "biodiesel" or "powered by veggie oil" on the back.

Good luck!

(Just did a top end rebuild on a 1979 VW Rabbit 1.5L diesel, and it is still going strong, all 45hp... Now not even a wisp of smoke at 2500rpm. )

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Looking for Early 108 windshield surround wood in decent-to-good condition.

Obligatory 200D comment:

Oh yeah, what's your definition of accelerating in a 200D??

Was the smoke even behind you, or was it just a cloud, enveloping the car?



LOL!

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Looking for Early 108 windshield surround wood in decent-to-good condition.

The only car where the quarter-mile is measured with a calendar .

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

Thanks all for the pointers and heads up.

Yeah, the car is by no means fast but it can certainly get going pretty well for 55hp.

How much does an IP calibration usually run? I think it would be pretty beneficial. As it is, it took near a min straight cranking after a full glow plug cycle for it to get going with a cold start (70F ambient) which leads me to believe something isnt quite right.

I also still wanted to know what is the proper position of the heater valved under the dash for the heater to be off?

Also, is there any guides for the W110 as far as repairs or perhaps an online parts catalog?

Thanks!

Welcome to the slow and neglected Mercedes group

Not to familiar with older diesels but using the general rule since working on my w123.....start with the basics before jumping into the IP configuration.....

I am going out on a limb but I think this model also needs valve adjustments.....

Pull the tank and clean it good, on the w123 there is screen that gets clogged.....replace all rubber fuel lines....

Replace the fuel and air filter or clean the oil bath filter....

Have the injectors rebuilt...

Change the oil in the IP and car....

Upgrade to pencil glow plugs....

And don't forget to do some heavy freeway driving to burn the gunk out....

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you have a W110 diesel. There are few different thngs that have to considered first.
1/ adjust the valves.
2/change the oil and oil filter ,replace the aircleaner element or wash the oil bath and reill with clean oil.
3/ check the external condition of the mufflers. If they are a bity ragged,replace them because they will block up inside when rusty.
4/ Clean the fuel tank .The center drain bung is also a filter and there is Diesel bungs and Benzine bungs. Never use a Benzine bung on a diesel car!.
Change the fuel filter(s) .
5/ Check the resistance of each glow plug. These old large style glow pluga are as slow as a wet week when starting from cold. Even on my W115 240D it takes forever to get them hot enough for a dead cold start.
Consider swapping to the more modern style of pencil glow plugs because they are faster and easier to buy . You will need to get a resistor system from a four cylinder W123 Diesel to make them work properly . Glowing should only take a few seconds then.
While the plugs are out,get a compression test done AND a leak down test to make sure the valves and rings are servicable .
blowby is a sad fact of life with these engines but excess blowby means worn bores and pistons.
While that is being done,get the injectors overhauled. Pumps are precision engineered items and do not wear much. What does happen though is the leather diapragm in the rear part of the pump fails. You will see a line from the throttle body to the fuel pump. Remove one end,clean it and then suck on the end to see if a vacuum in produced in the diaphragm housing .
These engines will still start and run with a shot diaphragm but smoke really heavily.
Once that is checked and you are sure it is 100% OK, get the engine to running temp..minimum 180F , and go up a big hill or similar to check the smoke. The throttle is adjustable to allow more or less air in relation to the injection pump.
Adjust that first so that the throttle opens properly . As a rule of thimb the throttle is opened fully and the position of the arm on the Injection pump checked. the lever should be hard against the stop at full throttle.
If there is ANY wear in the ball ends of this linkage,the throttle cannot be adjusted correctly so replace any worn ball ends.
Idle is adjustabler from the drivers seat. there is a small knob,the same shape as the headlight switch . turn to the right to increase idle when cold,when the engine has warmed up,you can then turn it back until it idles slower and smoother.
it is entirely possible that someone has cranked up the idle to cover fuel delivery hassles such as worn injectors and blocked fuel systems.
Good Luck!!,

The Best online source for parts informationis here and the electronic parts catalogue or EPC that is run by mercedes . In my part odf the world you need to be a member o a Mercedes Club to gain access but in the USA i think you can get free access on line somehow.

There are two heat levers, one for the driver and the other for the passenger. Move toward the center on both for heat off. The engine does generate heat, so you may feel some heat on the highway. Originally they had underdash panels with insulation to prevent this.

For the official Mercedes parts manual, subscribe here:

EPC-net Online

A US credit card is necessary for verification that you live in the US, but it will not be charged and the parts manual is free.

If the car was sitting for a while (or years) and not driven, put some fuel conditioner in and run a couple tanks through it. The smoking might subside as everthing gets cleaned out. They do smoke some upon acceleration but should not be a mosquito fogger.

As mercmad6.3, wouldn't hurt to get a compression check before going too far. Should not take more than one glow plug heat (approx. 20 sec. until the dashboard resistor gets red hot) for the car to start when the ambient temperature is 70 deg. May stumble for as second or two after starting till it gets going, but that's not out of the ordinary.