Just purchased a 1984 300D Turbo - SUPER sluggish!
 

Well, to be more accurate I am going to buy it tomorrow. It was going to be about 20 minutes ago, but the seller forgot the title. Oh well. He's my physics professor, so it's not like I don't see him frequently. Regardless:

Some background on the car: Recent fuel filter and oil changes, but not valve timing. Not sure what kind of shape the valves or timing chain are in. ALDA cover has been taken off, so I suspect that someone has adjusted it before, but I haven't. It is currently running on petro diesel, although it usually runs on biodiesel.

Last week, I took a test drive. Just as he warned me, the acceleration is poor. From 0-10 is almost nonexistant and 10-30 is pretty bad too. What happens is that I stomp on the pedal and wait for about 3 seconds, and the engine just idles for 3 seconds. Nothing. Then all of sudden it picks up gradually and then starts to race. I didn't get to take it over 30(on-campus speed limit), but he tells me that it does better after 30mph.

What this leads me to beleive is that the turbo doesn't have good pressure. However, that is one of the things that I haven't researched much at all. Can anyone tell me if my suspicions about the turbo are correct, and if so, what my most likely fixes are? I'm still looking for an owners manual and a Hayne's/Chilton's.

Thanks in advance!

Check the alda line from the intake if it's plugged it wont accelerate worth a damn. I finally got around to checking pump timing on my car and found it was off by quite a bit. Boy what a difference in power and it ran well before the pump adjustment.

Also check just to be safe, the Throttle linkage.

The pivot ball behind the accelerator might be bad which in turn doesnt allow the throttle rod to move full length when you press on the accelerator..

Its more likely that the alda line is clogged though. :)

Good luck, and congrats on the new ride!

Cruddy Banjo Bolt?

Hmm, three votes for the banjo bolt. I'll check that first.

Also, I neglected to mention that the first 50% of the accelerator pedal travel does nothing for RPM, if you push it to 50% and leave it, nothing will happen. I am definately planning on checking the throttle linkages.

Slug
 

Also check the overboost lines and the switch that they run to.
That was bad on my car when I bought it.
JOHN

I vote on throttle linkage. Had it misadjusted on my 77 and it ran like there was an anchor attached to it. Adjusted and it runs very well. Also it didn't have nothing the first half of the throttle.

sorry guys
 

sorry guys its the transmission and the
pause that your hearing is second gear slipage
were your in drive it starts off in second...

try the k1 kit...a new filter and a quart of trans X and
call me in the morning...

People keep saying it starts in second,, Butterball never does. In fact, I don't think Alex or Grocery Getter do either. My vote is for the ALDA line.

Nope, the same thing happens in park.

Well, you can forget about chasing the turbo.........the ALDA........the banjo bolt.......or any of the lines from the manifold to the switchover valve and onto the ALDA. The lack of boost is not the problem here. The reason is simple. There is no boost below 2000 rpm and your problem is between 700 rpm and 1500 rpm. Once you finally get a bit of boost..........."it starts to race" as you mentioned.

So, with clean fuel filters and an unrestricted tank screen, it's time to check the camshaft and injection timing. My bet is that one or both of them are horribly late and the engine won't perform.

And a valve adjustment.

Yeah and check the fuel tank for a vacuum. Pull the cap before test drive.

When I got my SD is was horribly slow at any speed...

WITHOUT an ALDA adustment, adjusting the valves helped immensely.

how does the car start?

you will have to sell it cheap at a discount to me......





Just like how adn why I got my W123 for the price I did.....same problem...took 5 minutes to fix once it was in my name..


http://brandon.importtransmissionexc.../300dright.JPG

Try this to get the ALDA sytem soot free.

http://dieselgiant.com/mercedesaldaboostsystemservi.htm