Hi All:

First off, thank you all for your answers to my previous dumb questions ...

Now on to the meat of the problem. My '81 240d smokes and it's destined to be my so's ... and probable wife's ... daily driver. She doesn't like smoke, & I tired of being single (I'm 33!) so _please_ help me out here...

Here are my observations:
1) It smokes a _ton_ at startup. See attached photo and you'll get an idea. This is about ~1 minute after startup.
2) There's a lot of blowback (as evidenced by removing valve cover & observing vapor + oil in intake).
3) Oil consumption is large: at >1q / 500mi.
4) Smoke diminishes with time; the warmer the car, the less smoke there is.
5) The compression looks great (!):
Cylinder 1: 300 psi.
Cylinder 2: 310 psi.
Cylinder 3: 330 psi.
Cylinder 4: 320 psi.
6) The car starts on a dime; one turn & it's running no matter what the temperature.


What do people think??


Based on prior posts in this n.g. the valve stem seals don't make a huge difference, or do they?

JimSmith suggested the injection pump may be to blame ... any suggestions about diagnosing this?

I'm truly perplexed & my sex life is at risk here. Any suggestions would be greatly appreciated.

Many thanks;
sga

Attached Thumbnails

 

Smoke sort of looks bluish in the pic to me. Oil? I don't understand though why you'd have significant blowby and oil consumption with such good compression numbers (unless the numbers are wrong). How would the oil be getting into the cylinders? There is apparently another way of check ing the cylinders for the source of leaks out (and for oil to get in) by pressurizing the cylinder, but I have not done it.

Is the fuel tank dirty? Recent fuel filter change (easy thing to do). My 300D made a lot of smoke like that after the fuel tank got contaminated with some motor oil, and it resolved for the most part after draining and refilling with fresh fuel. My 300TD benefited from a smoke standpoint by a switchover to biodiesel. It doesn't smoke at all now (which is a disadvantage when I want to smoke a tailgater).

From the injection standpoint, you can pull and test the injectors for proper spray pattern and check the injection pump timing (fiddly, but not too hard). As far as internal fault to it go though, I though it was a thing left to a pro in terms of testing, but if your car is running.... Perhaps it could be the injector if somehow the lubricant oil is getting in to the fuel stream, though I'm not sure how this would happen. I think a diesel service center where you might have the injectors checked could check the pump for you.

Another standard thing to check on the forum is the valve adjustment.... Also look in the coolant to make sure that oil's not getting in (and coolant into cylinder). Some others may be able to think of a couple other things to check, but there ain't a lot more I can think of.

__________________
Der Panzermann und Fraulein Fahrvergnuegen

1991 420SEL 201K "The Big Blue One"
1985 300DT 205K chassis/285K engine nee California emissions "Goldbug"
1983 300TDT 255K "The Womble"
1983 300 DT 214K "Sea Sprite"-Rear-ended a truck
1983 300SD 285K "The Donor" Gave his life so that others can live
1980 500SL Euro 105K "Der Panzer"