So I am finally getting around to fixing my smoking 1976 w115 240d. Let me give you a very brief history of the issue before I move on to my current problem: The car was a reliable daily driver for over six years, with a few minor mechanical issues here and there over that period of time. Then the injection pump failed and I had it rebuilt. When it was later installed by my mechanic, it smoked — not terribly — but it smoked and it did not smoke before. I lived with this for awhile, until I was fed up with it and took it to someone else to have the timing adjusted. When it came back, the smoking was worse and the it drove terribly. Thats when I decided to take matters into my own hand.

I started with a valve adjustment, and then did a injection timing using the ************** kit. The valves only needed slight adjustment. But the timing... I followed the procedure: top dead center, 24 degrees, bled the system, and when I tried to adjust the timing by retarding the pump to its max (pulling it away from the engine block) it was still a steady stream of diesel fuel*— no drip. Only when I set the crankshaft to about 10 degrees does it come to a drip. I have also played with the govenor (the little screw) on the back of the pump — but if someone could explain exactly how the govenor works, that would be helpful.

The next thing I am going to do is a compression test. Could low compression affect the drip timing? Timing chain issue? Does anyone have any suggestions?

I made a video of the car and its smoking before I did the valve adjustment and attempted the timing https://www.youtube.com/watch?v=EglTdKFqBS8

Thanks

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1976 w115 240d "Bleu"
1979 w123 240d "Biscuit"

Whoa whoa whoa... one thing at a time.

I'm not familiar with the M Source method -I'm assuming by the asterisks- but retarding the pump to the max is certainly not something you should be doing. Most likely, your timing is already retarded. I've adjusted my pump timing quite a few times, so below is solely based on my experience. Hopefully others will chime in.

Without knowing anything else about the state of your engine, 24 degrees is as good a place to start as any. Personally, I've found 25 to be a sweet spot on my engine, but mileage obviously varies.

You should be making very very minute adjustments to the position of the pump to achieve proper timing. The closer you push it toward the block, the slower that stream should become until it is eventually a drip. If you've moved it all the way forward (as close as possible to the engine block) and it's still streaming, you may need to remove your pump and advance it by a whole tooth. Have you read the drip timing DIY/wiki on this site?

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1981 240D 4sp manual. Ivory White.

Thanks for the quick reply Shern. I played with this for a few hours, moving the pump all the way towards the engine and as far as I could away from the engine with the same constant drip. The next step it seems is to take the pump off and make sure it is aligned correctly. What about this "teeth advancement" how many teeth are we talking about? Should I also test the chain tension?

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1976 w115 240d "Bleu"
1979 w123 240d "Biscuit"

Again, one thing at a time.

What is your method? You didn't reply to my question about reading the DIY on this very site. Is the rack fully wired? Are you absolutely certain you're on the compression stroke?

We're talking a SINGLE tooth. This is not something I've ever had to do, though there are others (look archive) who have. Has your pump been removed before?

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1981 240D 4sp manual. Ivory White.

I have followed the diy article you linked. I will take another stab at it, making sure I didn't miss anything. Yes the pump was removed and rebuilt, then reinstalled. The car smoked slightly after that, I then had another mechanic attempt a drip timing, it smoked and drove considerably worse after that. I am not sure whether or not he took it out.

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1976 w115 240d "Bleu"
1979 w123 240d "Biscuit"

In that case, I suspect they installed it a tooth off-time.
You might try starting from scratch. I haven't done this, so can't offer much guidance, but there's a correct crank position for reinstalling. Might be better in your hands than theirs.

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1981 240D 4sp manual. Ivory White.

See posts 2 and three. I don't know if it applies to your year and model. The wrongly marked pumps are timed at a different degree on the crank damper. I don't remember what it was.

removing injector pump OM617

Does your pump have a vacuum governor or a mechanical one?

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84 300D, 82 Volvo 244Gl Diesel

This is the IP in question. Is that vacuum?

Attached Thumbnails

 

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1976 w115 240d "Bleu"
1979 w123 240d "Biscuit"

It runs off of a venturi in the intake manifold. IF there is a vacuum leak it puts out more fuel and smokes.

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84 300D, 82 Volvo 244Gl Diesel