I am working on a 1983 300sd, that seems to be way flat on the bottom end. Ran a compression test and came up at approx 310 -320 across the board, adjusted the valves. The engine starts super easy but it seems like the first 1/3 of the pedal does not do to much. Once the engine gets wound up it is ok but getting there takes some time. what do I need to do to make her somewhat responsive?

If I understand your question, you are saying that the car lacks throttle response for the initial 1/3 of the pedal's travel?

If you are used to driving American or Japanese cars, you will find an MBZ gas pedal to be quite different, especially on a 300sd. What I mean by this is that older MBZ's have a long pedal travel and have a much more progressive response than does an Accord or Tuarus, for example, which will jerk your head back if driven by a beginning driver.

The only thing I can think of would be to adjust your throttle linkage possible. I am not sure of the procedure, but I am sure other members will chime in shortly.

Mike

I do understand that the diesel is quite a bit more sluggish as it seems that most of my vehicles are diesels in fact you might even say that I have an illness (my wife does), as currently I have 6 diesel vehicles running around my house. But this one seems to be unusually unresponsive in the lower end. Even my 2 vw jetta tds, and my 1980 td wagon (na). are much quicker. Even in nuetral it seems to be real hesitant to come up on the RPMs. It is not even possible to spin the tires in my gravel driveway.

from a post i submitted earlier "went to look at an 83 300d t station wagon. manual sunroof. not all that bad looking really. but so slow. must have taken 10 seconds to accelerate to 20 mph. then all of a sudden the booger took off and was normal. but every start from stop was again so slow. what could cause such a condition? the man did say his wife did not like driving this car. no wonder why!"
i too am most familiar with the fuel burners as i have presently 4, 5 and 6 cylinder mercedes models.

Check the boost lines and the banjo bolt coming off the back of the the manifold. They can all get plugged and cause a lack of added fuel. My 300SD was sluggish when I first got it and after a combination of running it a few hundred miles on the highway and cleaning the black sludge out of the banjo bolt and portion of the line it got much more responsive.

It may also be time to check the chain for stretch. A worn chain will give you late injection timing and valve timing. Late valve timing can also make pickup bad at low speeds.

Could it be starting off in 2nd gear instead of 1st? I notice my 84 SD not going into first unless I am starting from a dead stop, and acceleration in 2nd gear at very low speed does not inspire confidence in traffic.

Jerry

The Turbo boost doesn't kick in until the engine reaches 2000 rpm. This gives the car a very slow off the line until you get up to about 25 mph. and then it depends on how soon your transmission upshifts which is going to lower the rpm again.

This diesel needs to be driven pedal to the metal if you don't want too much honking behind you.

0-60mph in 15 seconds is about as good as it gets in an SD. How does yours compare?

Sixto
91 300SE
87 300SDL
83 300SD