Need purchase help 85 300d 332k - PeachParts Mercedes-Benz Forum

winmutt · #1 01-13-2007, 03:49 PM

I found a 85 300d on craigslist for cheap.Of course there is nothing worse than a cheap mercedes.However here is what I know about the car. The current owner has replaced the turbo (frozen when purchased), the oil lines and there turn fuellines.The problem?The car has no off the line torque.Once its underway the car seemed to have no problems going(turbo spunup etc)but I had to keep it floored the whole time.I cant hear any specific nailing.Today I did a purge (leftover fluid was clear), and serviced the alda. A mild improvement in torque. I also cracked the fuel lines and did not notice any particular difference in sound between any of the cylinders. I also did a Italian tune up and the car seems to be behaving better. I did a tea kettle test and it was about what I expected for a car with that many miles. There was little to no oil smoke how ever a good amount of oil smoke came from between the IP and engine block. Under load there was a small amount of black smoke. At idle the car is indistinguishable from my car and it revs just fine manually pulling on the throttle and when it was in L or R the car seemed to behave about normal.There is definetely a vacuum leak in the system.Brakes have little power, car does not shut off on its own, etc etc. So my question is, what else can be the problem?

Brian Carlton · #2 01-13-2007, 04:05 PM

Quote:

Originally Posted by winmutt

So my question is, what else can be the problem?

........the problem is that you are a sick man and you require old tired M/B's as an antidote to your problem............vehicles that will give you nothing but "challenges" for you to continually fix..........that is the problem.........

Mismost · #3 01-13-2007, 06:40 PM

Just a wild hunch here....but did you check the throtle linkage "knuckle"...that thing-a-ma-bob up on the firewall? Seems like I've read of a similar problem and that was the cause.

another wild hair...brakes dragging...wheel bearings

But, you gotta admit, Bryan did make a good point!

winmutt · #4 01-13-2007, 06:46 PM

The brakes def drag. one of wheel bearings is shot as well. i think for $500 id be a fool not to get it. and i know im a sick man tuspid spacebar broke and im cutting and pasting a space in this reply.

#5 01-13-2007, 07:06 PM

Quote:

Originally Posted by Mismost

Just a wild hunch here....but did you check the throtle linkage "knuckle"...that thing-a-ma-bob up on the firewall? Seems like I've read of a similar problem and that was the cause.

!

It happened to me as well. The dealer told me that they sell a bunch of them and keep one in stock, if that tells you anything.

Knightrider966 · #6 01-13-2007, 07:33 PM

With that kind of mileage, I'd do a valve adjustment and even a leakdown test! That can make a very big difference in power.

winmutt · #7 01-13-2007, 07:58 PM

Quote:

Originally Posted by John Holmes III

It happened to me as well. The dealer told me that they sell a bunch of them and keep one in stock, if that tells you anything.

I can't find anything here on linkage knuckle. got a part number?

Mismost · #8 01-14-2007, 02:10 AM

Look here

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1OZ0OB9FZ1ZR04GEXT&year=1983&make=MB&model=300-DT-001&category=C&part=Throttle+Bushing

they call it the throttle bushing..pivot point

just seems odd to me that runs well at highway speed and idles ok...oughta be SS (simple stuff)

winmutt · #9 01-14-2007, 02:27 AM

Quote:

Originally Posted by Mismost

Look here

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1OZ0OB9FZ1ZR04GEXT&year=1983&make=MB&model=300-DT-001&category=C&part=Throttle+Bushing

they call it the throttle bushing..pivot point

just seems odd to me that runs well at highway speed and idles ok...oughta be SS (simple stuff)

Well I just put the down payment on it and maybe if I am lucky the guy will let me take it home and send me the title when I pay in full. I'm guessing its just a combination of things. What exactly does this throttle bushing pivot point do?

Brian Carlton · #10 01-14-2007, 11:26 AM

Quote:

Originally Posted by winmutt

The problem?The car has no off the line torque.Once its underway the car seemed to have no problems going(turbo spunup etc)but I had to keep it floored the whole time.

OK, so I see that you're committed.

The problem is more than simply a lack of off line torque. If you must keep it floored the whole time.........you may not be getting any boost signal to the ALDA.

First do the typical cleaning and/or replacement of the banjo bolt and the lines to and from the overboost valve. Diesel Giant has an excellent pictorial of this entire procedure.

Then, take it for a 0-60 time and report back with results. Have to know if you've got a turbo problem or just whether you need some ALDA or tweaking of little odds and ends.

If you happen to have a boost gauge, T it into the line to the ALDA and route the gauge into the cabin while you drive it. Note the boost at various operating modes and engine speeds and report back. Definitely note the boost at 3000 rpm or more at maximum power.

winmutt · #11 01-14-2007, 11:14 PM

I got her up to 70 on the way home and she was just sailing. The transmission simply went out of gear and I spent the rest of the way home unable to get it out of 2nd. I plan on putting a 4 speed in this anyways but would like to sell the transmission and know that it is functional.

JimmyL · #12 01-14-2007, 11:22 PM

Congrats on the car. I don't think your tranny is very marketable at this time......