I got black smoke blowing out the tail pipe when I throttle my newly aquired 81 300SD.
It came with the tank 3/4 full. I topped it off since, because I thought the old man who had it, may have filled the tank with heating oil !?

I think it's gotten a little better since I topped it off, but maybe there is something else I should look at.

I don't think there could be so much residue piled up in the muffler that after 200 miles it still blows black smoke when I throttle it all the way?

I know the car was locally owned and driven just around town. It is otherwise spectacularly well maintained, near perfect condition with less than 200K miles.

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take it out on the highway and drive it like you stole it

then ya know.. adjust the valves, check the alda, verify the turbo works..

I would say that you need to run it a lot longer than one tank of fuel (or a partial tank as you indicated) to clear out the old soot buildup. Are you getting puffs of black smoke or an extended output of black smoke? If just puffs, then the soot clearing process is continuing. If extended, you either have a LOT of soot buildup to clean out, or for some reason the fuel is not burning completely.

Also, on a new used diesel 617 one of the first things that usually needs to be done is a valve clearance adjustment. This has an impact on starting and burning fuel properly.

Ken300D

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1982 300D at 351K miles
1984 300SD at 217K miles
1987 300D at 370K miles

Ditto, the valve adjustment and while you have the valve cover off, check the timing chain for stretch as timing can also be a factor for black smoke. Change the fuel filters and then give it a good 2 hr. highway run.

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Sam

84 300SD 350K+ miles ( Blue Belle )

I like the idea of the first line ... thing is, I already did that, needed to mention I have no plates on the car, only a temp reg in the windshield ... so I got pulled over by a youngin, who told me how it smokes whenever I hit the gas ...

I decided not to be the smart a** and played innocent ... He meant 'make sure you put the plates on as soon as you get them'...what the heck he thinks I'm gonna do ... ???

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Also check the air filter. If its plugged it will contribute to the smoke.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

Airfilter is a good idea!!! Engines need to breath

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ditto, definitely start w/ the easy stuff, the air filter 1st, then ease into the other stuff that was mentioned.

BTW its ok for the engine to burn HHO, just don't get caught by the authorities.

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Cheers,
Robert

Thank you guys!

It starts up like a rascal and runs pretty smooth. It idles a little high and has the 79 degree thermo in it, which is good for summer time when I go to Vegas ...
I think those old folks just drove it around town like a snail-train for 20+ years ....

Seems like the smoke is lifting slowly...I'll follow up on the suggestions you guys made!!

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You should get a little black smoke on full throttle. Black smoke is a sign of overfueling and a little black smoke on full throttle shows you have as much fuel going to it as it can take. Plugged air filter produces black smoke because overfueling is another way of thinking of underairing.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Yes black smoke is a sign of incomplete combustion. So is white smoke.

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42