I hope it helps solve your rough idle. I’m pretty sure euro cars have an M pump with different delivery valves and washers than I linked above. You may already know that, just mentioning it in case.

__________________
Garage:
1983 300TD
1985 300D
1993 190E 2.6

Social:
Metric Restoration on Instagram

Man, thank you so much. Over the last 8 months, I have gone through the same list of actions to try to fix my idle and clattering problems. I actually replaced my DVs with pre-owned ones that I thought were good. I assumed DVs were not available anymore so I thought this was the best I could do. They actually looked fine.



I ordered the DVs and Springs from the links above and my problem appears to be solved. By the way, there are two versions of DVs for the OM617, the ones I received were the updated version. The site is in England, so it took a couple of weeks to arrive.


Thank you again for the links. I had tried everything! Happy New Year!

Let us hear the difference.

Updating this thread since I thought my problem was solved when I replaced the delivery valves, but unfortunately the shaking idle still remains

Since my last post, I've put in a rebuilt injection pump from Yankee Diesel and injectors from greazzer on this forum, which also hasn't solved the problem.

Here's an updated video showing very clearly the rough idle https://youtu.be/4inl01uWoEw

Check post #1 for a list of what I've tried so far.

Please help me solve this mystery!

__________________
Garage:
1983 300TD
1985 300D
1993 190E 2.6

Social:
Metric Restoration on Instagram

Appears to be injection pump rack oscillations, to test push down slowly on stop lever
if engine smooths that"s it.
What to try: make sure linkages are not holding pump off of rest position.
Rack damper not strong enough, grind locking nut to half width, make sure
does not keep pump from returning to rest.
Problem is in pump,not the first one,that"s why Mbz Came up with the damper!

The rack damper did not work on all pumps, and if you received a rebuilt that it did not
work on Guess What! YA you got it, jumpy idle,not not a condition rebuilder can test.

Thanks for the suggestions. I have disconnected the linkage to the pump entirely and it still shakes. I'll try a slimmer locking nut tomorrow and update with my findings.

Keep the tips coming! I'll try it all. It's hard to look good for my date in a classic car when it shakes like a paint shaker at every red light

__________________
Garage:
1983 300TD
1985 300D
1993 190E 2.6

Social:
Metric Restoration on Instagram

Yes, I know about the date thing, my 300sd does not shake, lucky me you would think,
worked on Mbz for many years, have never seen one like mine, ENGINE jumps up and
down. What a ride!

Just remembered, there is a valve in the pipe connection between the injection pump
and fuel line to injector, called Relief Orifice, said to stop fuel back pulses from reopening
injector. If defective could cause smoking (fuel injected at wrong time), is it also possible
that engine noise and idle quality could be affected?

We call that a delivery valve.

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84 300D, 82 Volvo 244Gl Diesel

So many of these threads appear to be solved by doing something or other to the rack damper.

Wonder why these weren’t included on the om616 pumps…
Feel like I could use one.

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1981 240D 4sp manual. Ivory White.

The delivery valve is under the relief orifice, name given by Mbz.

616 engines did not have the rock and roll problem, came about with the turbo engines,
according to Mercedes.

I’ve taken those pipe fittings off many times. In order, there’s a crush washer, a delivery valve assembly (plunger and barrel) a spring, and the pipe fitting itself.
I’m not sure which part is the “relief orifice.”

Do you have a part number?

__________________
1981 240D 4sp manual. Ivory White.

Above the delivery valve spring inside the pipe fitting, not replaceable that I know of.
Possible with pipe fitting?
Mercedes said that they do sometimes fail.

If you look in different sections of the Mercedes service manuals about the same part the translation to English often suffers and depending on where you are in the manual the parts name is different and that name can also be different in the parts lookup.

I worked in a fuel injection shop for 5 years in part rebuilding Fuel Injection Pumps, and I know what the parts are called here in the US and I also have a fair idea what our members call a lot of the parts.

US parts sellers also sometimes have different names for the same part. Rack Damper Pin Equals Governor Idle Pin depending on the seller.

Since the fuel injection pumps in this case are made by Bosch it may be Bosch has entirely different names for their parts compared to the Mercedes names.

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84 300D, 82 Volvo 244Gl Diesel