I picked up one of these last Thursday, and intend to (eventually) use it for a daily driver. I drove it around 132 miles to get it home, and I have to say that I'm super impressed...I've been reading how everyone says the 240d is slow (and don't get me started on the 220 ), but I found performance to be on par with the Honda I've been driving lately. Don't get me wrong, it doesn't hold a candle to my 350SL, but I was still pleasantly surprised. If I estimated right, I got 32mpg on the way back, but I won't know for sure until I fill up again.

Mechanically, it seems perfect--since it's a 5 digit odometer, I'm not sure about the mileage, but I'd guess it's around 230k. One thing, though: it sounds to me that the idle is a little high. Could someone take a listen and tell me one way or the other? This is my first diesel, and I don't really know much about them...I was wanting this to be a learn-as-I-go kind of thing
1972 Mercedes-Benz 220d idle - YouTube

PS: I drove it around for 15 mins or so to get the engine fully warmed up, and the idle speed adjustment inside the car is as low as it can go.

Thanks,
Brandon

I would be very impressed if someone, by ear, could estimate your idle rpm. A relatively cheap alternative if it is important to you:
CyberTech Digital Photo Laser Tachometer Non Contact Tach: Amazon.com: Industrial & Scientific

__________________
1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

The idle is definitely fast...sounds like mine when the fast idle control is turned up. I'll venture a guess of 1000 RPM.

Assuming the fast idle control isn't sticking (mine does sometimes...check the cable end at the linkage above the injection pump), it appears the actual idle speed control is actually on the intake manifold side...the big screw right next to where the air cleaner elbow connects to the intake.

You might also check to make sure all the many linkages move freely and oil them if needed.

**I forgot to mention, if the injection pump's diaphragm is bad, that can be a cause of a fast idle (and usually a lot of exhaust smoke).

__________________
1976 240D "Katja"

^^^indeed

way too fast idle - diaphragm is a likely problem - see chapter 07-215 in the W123 FSM

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I proclaim myself "impressed!"

Kidding aside, I have found that $14 tach to the super helpful at getting the linkages and idle set right on my 220D. I had a sawing idle which was resolved by getting the linkages set at their correct lengths.

I vaguely recall somewhere in the FSM that if you don't have access to a tach, they suggest lowering the idle rpm until the engine stops running smoothly or until the alternator (generator) light comes on. The idle adjustment, as mentioned above, is a screw on the inlet butterfly valve. Super easy to do. You also want to be sure that your idle adjust cable is not set too tight. Even if you have backed it off all the way inside the car, if it is set wrong in the engine compartment, it could still be causing an elevated idle.

Good luck.

__________________
1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

Ha ha! Good eh? I bet the engine's running at about 1500 rpm (just a bit more than what katja thinks) - my mk1 ear drum is a finely tuned instrument of automotive fault detection - when I get my upgrade you'll be able to plug me directly into those OBD-II sockets...

...half man half diagnostic kit...

...when I get the mk3 upgrade I'll be able fault detect Boeing 747s as they fly over head...

...you would have thought that the sky was the limit but actually with the mk4 upgrade (which is still in development) I'll be able to do the space shuttle and the communication satellites...

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Sweet Jesus is that thing idling fast, this is what I call the first signs of a run away engine....keep a pair of snips close by to cut the fuel line when it starts racing....don't ask me how I know.....

You have a leather diaghram in the rear of the injection pump, this is torn and cause high idle....they can be changed out but there is a little pin that needs to be removed, and yes its one of them cussing screaming kicking the tires type pin..

Picture


Good read
1973 220D W115 Injection Pump Gasket - Benzworld.org - Mercedes-Benz Discussion Forum

__________________

Governor Diaphragm Test
http://www.peachparts.com/shopforum/diesel-discussion/313733-74-240d-grey-smoke-questions.html
What are the symptoms of a bad IP Governor Diaphragm? Has Symptoms, Cost of Diaphragm, description of how governor works.
http://www.peachparts.com/shopforum/vintage-mercedes/223548-what-symptoms-bad-ip-governor-diaphragm.html

__________________
84 300D, 82 Volvo 244Gl Diesel