W123 300D Idle Adjustment

Is there a single adjustment for the idle on the 5-cyl. 617 diesel? Or , is there an njector adjustment required?
My idle is too high, and I don't know what the procedure is.

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I don't have an answer for Randall, but I have a related question: Why don't later-model M-B diesels have an idle adjustment control on the dash like the 220D did?
Or if you prefer, why did the 220D have one? The only other modern cars I'm aware of that had this rather odd feature were the early rotary Mazdas, e.g., the RX-2.
Geoff
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Look between the injection pump and the block where the "idle stop screw" is located (it points up at you). It has a lock nut that can be loosened with a 5/8" deep socket. Then use a large and long flat blade screw driver to unscrew the adjustment. Try one 360 degree turn and lock it. Drive it a a few days and adjust again if needed but keep a record of adjustments made so you can retrace if necessary.
While it may seem too fast at hot idle the motor also has to idle reasonably at cold start so test it through the full range of driving.
As to the other poster's question, the later engines have a 750 rpm idle speed governor inside their injection pumps making a hand adjustment moot.
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On Jan 23, 11:23 pm, "-->> T.G. Lambach <<--" <"T.G. Lambach at NoHamorSpamcomcast.net"> wrote:

Great, Tom. Thanks. I will do this and keep a record. I am also going to try to hook (back) up my manual idle control, which would help on the cold starts.
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On Jan 23, 11:23 pm, "-->> T.G. Lambach <<--" <"T.G. Lambach at NoHamorSpamcomcast.net"> wrote:

As an addendum--I set the idle this morning according to the procedure you provided, and now have the engine purring at proper idle speed. Why it increased, or was set that high, I don't know. It could have been in conjunction with the disconnection of the manual idle speed control--however, I don't know why that was done. I am trying to restore that functionality now.
Thanks again!
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