Hi I have a 1974 240d that smokes grey all the time, alot more when hitting the pedal. I put injectors from my parts car that wasn't smoking, and adjusted the valves. looking around says to change valve seals or set timing, and i was wondering if my timing was bad would the car run OK? because the car runs fine and has as much power as my 83 240. also would oil in the intake manifold make the car smoke grey? answers appreciated.

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

Oil can certainly cause smoke. What does it smell like?

The timing doesn't have to be too far out to cause a smoking. You won't necesarily lose much power or suffer any worse fuel economy, either.

How is your tiiming chain stretch?

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1974 240D "Boldie" 170K.- New timing chain/freshly rebuilt IP/replaced valve seals/injectors/upgraded stereo/new Bilsteins with Yokohamas/fresh paint and rocker panels plus lots of welds.

How's your coolant level. Could be a blown head gasket and you're burning coolant. Burning oil usually makes blue smoke.

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The coolant is really clean and stays the same level and the oil level isnt rising. i still have to check timing stretch. also what are all the options for grey smoke is it just injectors valve seals and timing?

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

I had Hazy gray smoke on my Volvo Diesel after it sat one Year in the Back Yard waiting for me to put the Fuel Injection Pump back together and I drove it 6 months through the Winter not knowing the Thermostat was opening too soon.

Thinking that after all of the above might be sticking Piston Rings I dumped Marvel Mystery Oil into the Cylinders and let it soak for 1 week + 3 days.
It worked.

To shorten the above; the issue was one of compression.

Another issue can be it could be getting slightly too much Fuel due to your Pneumatic Governor Diaphragm being a little stiff.
I also think I read somewhere that over on the Manifold linkages there a an adjustment to change the Fuel Enrichment but I did not read about it in detail so I cannot comment for sure on that.

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84 300D, 82 Volvo 244Gl Diesel

You've got a rubber diaphragm in your injection pump and it has a hole in it. That's the symptom of the problem. Long thread on here with video from a guy who had the same problem about six months ago. Any remember the member's name so it can be easily found? He made really interesting videos.

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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

I came across that as well.

Consequently, I had my IP rebuilt to combat the grey smoking issue (100ft or better plume out the back at highway speeds). The diaphragm was found to be reasonably intact, but there was some wear in the metal governor housing causing leakage. I forget the technical name for the part, but it's a pin or pivot of some sort that runs through both sides of the housing.

Although I still have some smoke, it's nowhere near what it was before.

That being said, I can't rule out a mistimed injection pump. I timed the IP prior to having a new timing chain rolled in. The new chain restored the timing to correct spec and the IP had probably then gotten out of synch.

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1974 240D "Boldie" 170K.- New timing chain/freshly rebuilt IP/replaced valve seals/injectors/upgraded stereo/new Bilsteins with Yokohamas/fresh paint and rocker panels plus lots of welds.

how can i check this diaphragm? is it in the part of the injection pump with the hose coming from the intake to the pump?
also the circled lever in my car is sticking, what does the lever do i didn't look into it yet.

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

Yes. The thread I mentioned has the details.

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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

Here's that thread:

High Idle, White Smoke, shifting funny, HELP!! 75 240D

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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

lol i passed that thread because of the shifts and white smoke. there's a lot of good stuff on there. thanks for the link

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

i looked at the first video and the problem is similar to my car just my car runs a little smoother a little less smoke and when i hit the pedal the smoke wasn't as bad as in the video, and it doesn't stumble on start up. is the sound like it has marbles jumbling around normal? and about the lever when i looked inside today and it controlled a smaller flap behind the big flap. ill try to get a better look tomorrow.

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

Heres another picture. the red circle is what stays down but doesn't move back up when letting off the pedal. and in the green circle, i dont think i have that screw i got to check tomorrow.

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1974 240d
1983 240d -sold
1989 420sel with om606
1994 s350 turbodiesel - sold

I can't really tell from the picture but that looks like it could be the butterfly valve. If it is and it's sticking closed that will cause grey or black smoke because there won't be enough air for the fuel to burn.

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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

The flap behind the butterfly valve is there to prevent the engine from running backwards. It can happen on rare occasions if you engage a forward gear whilst running backwards. Here is a diagram:



Check if the governor housing is air tight:

How to test the pneumatic governor for leakage:

Do this test with the engine off. It can be done with or without removing the cable to the starter knob.

Here you see the pneumatic governor or the diesel pump. It is to the right of the red cap. The hose provides vacuum to the governor housing, the vacuum is produced by means of a venturi in the air intake. The housing must be air leak free, otherwise the governor cannot work properly and/or the engine will use more fuel.



Remove the air hose with a 17 mm wrench



Put the lever of the pump in the stop position, i.e. to the left (if you haven't removed the cable, put starter knob in the stop position, i.e. push in).



Now, while keeping the lever in the stop position, connect a vacuum gauge.



Release the lever to the normal position, the vacuum gauge should now indicate a small vacuum: 70-90 mbar or about 4 in Hg





This vacuum should stay constant.

If you haven't got a vacuum gauge, an easier test is possible.

Instead of connecting a vacuum gauge, put your thumb on the opening (while keeping the lever in the stop position:



Release the lever and keep your thumb on the opening



When you take off your thumb, you should hear a click. If you keep your thumb longer on the opening, you can check how long the vacuum stays.

Leakages are usually caused by a damaged membrane or by the poppet cam shaft bearings being loose. In the first case the membrane needs to be replaced, in the second case the bearings and O rings or the entire poppet cam cover.