Hello, everyone. I am Glinko, I am new.

I purchased a 1982 240D about 16 months ago. I've been getting about 23 miles per gallon, even after replacing the glow plugs and fuel filter.

Does anyone have an idea as to what's killing my fuel mileage?

I have one more detail, though I'm not sure if it is of importance. The gasket on the valve cover/cylinder head is bad, the engine block is wet with oil, and the car blows a moderate amount of smoke, even when it has been warmed up. Could this be my problem, or perhaps a contributing factor?

the mileage may not be abnormal. are you doing a lot of town driving? the valve cover gasket will not affect mileage. the smoking out the exhause may indicate weak rings, a possible source of some degradation of the economy. but i doubt that there is really anything wrong. also the glow plugs should not have any affect on economy either.

just drive it i think.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

haha, yeah, nothing but country back roads and stop & go traffic for me.

seems to obvious now that someone told me; my ignorance shines like a beacon.

How many miles? If it's got more than a couple of hundred K, then you might have worn injector tips pissing fuel instead of vaporizing. Getting em checked should cost about $10 each if you pull em yourself.

My 240D gets consistent 27-30 mpg, mostly driven hammer down at 160k miles with the original injectors.

Another possibility could be porous or leaky fabric coated fuel return lines.

And I think a valve cover gasket will run you about $14 online.

Finally, search "smoke" in the search engine here using the Diesel Forum specific option. It would help to know if it's black or blue, smells like diesel fuel or oil...... and *when* this smoke occurs - just at startup or under acceleration?

Hell yes - drive it until the wheels fall off. Welcome to the board.

192k

Actually, one of the return lines has been problematic. There have been times when I've pulled out of a parking space to find a nice little pool if diesel where the car had been sitting. Basically, the end was split, so I cut about half an inch off and put it back on. Hasn't been a problem since, although my fuel mileage is still pooty.

Right now I'm thinking that it's the type of roads I've been driving it on, as walgamuth said.

I shall.

EDIT: I have another question, but don't want to make a new topic.

my 240 has an automatic transmission, and I've figured it out rather well since I bought it. However, I'm still confused by the way it works. Allow me to explain:

When I put it in drive, it starts in second gear, not first. It will only shift into first gear if I'm at a stand still, and if I move the shifter into the "L" position.

Once I start to accelerate, it won't shift up to second gear until I move the shifter up, from the "L" position, to the "S" positon.

if I wish to stay in second gear (the "S" position includes second and third gears and shifts between them automatically) I can move the shifter back down to the "L" positon (while I'm moving) and it will stay in second gear until I move it back up to the "S" position.

Yeah, that might be a little confusing...

Is my transmission, like, defective, or is it supposed to function like that?

I think it is suppose to act that way, my '77 300D does

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1977 300D Lost coolant while someone else was driving
1983 300D Can't run without oil
1985 300SD (gone but not forgotten)
1990 300TE 4matic Sold
1991 Yamaha Venture
1975 Kawsaki 250 triple
1974 Honda 200CL
1951 8N Ford
2008 Wildfire 650C

I believe mercedes wants the injectors cleaned and checked every 100k. If this is reasonable to have done in your area you may want to consider unless you suspect previous owner or owners have already done it. Getting a nice spray pattern and having balanced pop pressures would help you know that at least that is done. A poor injector could be also causing a little smoke. You just never can tell what condition those injectors are in otherwise. Even cleaning with a diesel purge will not cure weak pop pressure problems. May not help your milage but may make engine sound better, run smoother and perhaps smoke a little less as you may even have one in there leaking down a little or with extremely poor pattern as well. Twenty three mpg in non highway driving with an automatic could be about average or even a little above average in my opinion. I own two standards. Also may be time to check for chain stretch as a preventative measure as well. Unless of course you know previous owner or owners have taken care of that as well.

My 82 240D gets about 23 to 25 mpg no matter if its city or highway driving.
What more can you expect from an engine that is over 20 yrs. old with over 200k mi.?
Drive it and enjoy.

17 year old kid, works for 7.00 and hour...diesel costs close to $2.60 a gallon around these parts. So yeah, fuel mileage has become a bit of an issue for me.

It's quite alright though, I love the car to death (my mother damaged the fender a few months ago and I literally had to fight back the tears. She paid to have it fixed and hasn't even sat in it since) and I'd continue to drive it even if it got 16 miles per gallon...I'd just complain more.

yes it sounds as if your driving habits and the auto make it about right. it of course should not smoke but if high mileage is to be expected, some. the return hoses should be replaced, it doesnt cost much and is easy to do. if one has cracked they all will sooner or later. i have had several sets of injectors tested. one of the diesel places always says they are shot. i also have some farmer brothers near here who are whizzes with diesels, tractors, trucks and mbs if they are in the mood. they also have injector testors and i think are more honest. bottom line is i have changed injectors many times and i can t remember a time it solved the particular problem i am having. so i recommend putting some injector cleaner through the car and just driving it.

the trans mission sounds as if it is working as it shuold. depending onthe year some take off in second and some first. a diesel should always take off in first in my mind but... oh well. if yours is the type tha tis supposed to take off in second there is a kit available to make it take off in first.

happy benzing.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I'm 18, work for 6.10 an hour, and pour all of it directly into my car (well, a lot of it anyways) Diesel here is around 2.29 (thats what it was today) reg gas was 2.35...premium 2.55 Some lady said to me one pump back with a gasser vw bug: "lucky you with a diesel, I wish I had one!!"

I get about 22-24mpg usually....today my average was "23.689" when I calc'd it.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

My '82 auto gets 23 on a regular basis. Best has been 28 hwy. I think the manual transmission 240's get a few MPG more but not much. Sorry.

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2002 500SL(Black/Black)
1992 300SE(Black/Black)
1992 190E 2.3(White/Navy)
1999 VW Jetta TDI(Pearl Green)
1986 SAAB 900 Base 3 door(White)
1983 Porsche 911SC(Chiffon)
1977 VW Scirocco(DiamondSilver)

This thread is enlightning to me. Have you younger fellows given any consideration to alternate fuels? If nothing else reading all the available material might prove interesting. The 240d is really a good candidate as is a non electronic engine with not particular good fuel milage. I have not given serious consideration to alternative fuels but that may change this summer. If your fuel is almost free what milage you are getting becomes less important i think. Also enough guidance out there to eliminate any guesswork now. Filled my home heating fuel oil tank today for 750.00. and that made me start thinking. It takes over 40.00 to fill my old jetta diesel tank now but did not seem long ago was maybe 25.00. Supposedly the price of oil is to continue upward.

you may want to check with local petro-distributers. The local petro-jobber in western VA sells B100. Due to a recent $1.00 federal subsidy, B100 is now cheaper than regular diesel in my parts. I had my heating oil tank filled @ $1.79 gallon, and my Biodiesel tank (that i've been filling piecemeal w/homemade biodiesel) for $2.20 / gallon IIRC (state and fed taxes included, so I can sleep well at night.....). I figured I was so busy this summer that I wasnt going to have time to make Biodiesel very often so I was either going to spend the money up front and buy enviro-friendly product for the same or less, or be pissed off that I was spending $2.25-2.40/gallon for the dregs of the worlds diesel supply....