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1984 300TD
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123 Posts
Discussion Starter #1
I hate inflicting grey smoke on the folks behind me in traffic so this really bothered me ... until yesterday.

After much casting about, with help from well informed and patient folks here on this board (300Dman and Govert70227 ... also Forced Induction) the smoke from my OM617 is nearly zero and may improve more with further adjustment.

After ironing out basics: IP timing, injector nozzles, verifying overall engine status thru compression check and leak down, monitoring oil consumption .... that is a big factor since if the engine isn't burning oil that tells you too much smoke comes from a fuel problem. If it is consuming too much oil there is a more troublesome expensive problem. My oil consumption is very low.

A simple adjustment of the ALDA immediately corrected the smoking diesel engine problem. IN my case adjustment of the central adjusting screw by a total of 180 degrees counter clockwise which presumably reduces amount of fuel injected. The FSM has some diagrams that give a short explanation of its function. I just

300Dmans experience with Bosch IPs sent me down that path of experimenting with the ALDA adjustment. It is important to adjust in small increments since the aneroid capsues can be damaged by too much adjustment. I simply used one eighth rotation adjustments and observed results. Counterclockwise resulted in improvement and after four stepwise trials the smoke is reduced to almost zero.

This is what these boards are great for.

Thanks to my three astute helpers.
 

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1984 300D
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5,070 Posts
In theory the ALDA is set when the Fuel Injection Pump is Calibrated and most likely does not need to be tweeked. But, you don't know what previous owners fooled with.

I guess what I am saying is that the ALDA can be adjusted and there is a proceedure for that. But, there is many other factors that can cause smoke that need checking. You should not automatically start fooling with the ALDA as your First Choice.

In fact there has been at least 2 persons who have had cracked inards in the ALDA due to over adjustment; well that is what they said.

There is a similar issue with the Governor Idle Pin/Rack Damper Bolt. A new one is only going to help if the other parts of your Engine that can cause shaking are within specs.
 

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1984 300TD
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123 Posts
Discussion Starter #3 (Edited)
It seems a little like you may not realize you and I have exchanged numerous messages in which the many factors have been addressed in this particular problem of my 617, they've been discussed, verified (at least by me) before going to ALDA adjustment as a kind of last resort. The success has been great.

As one of my astute helpers you can be proud you have offered input that has led to such good success, you are one of the few (in my experience) posters here who are rock solid.

I never found any FSM proceedure for adjusting the ALDA, your statement that observing tailpipe smoke is what the FSM tells you to do while adjusting ALDA put me over the top in proceeding with that. Based on FSM diagrams showing its function, generally, plus your warning against too much adjustment I jumped in as I have described in the prior thread ... ie the one titled OM617 too much smoke.

ON this one it did look like it could have been messed with previously. There is a metalic cup surrounding the adjust screw and its set nut with a plastic cap closure ... the surround was pushed out of shape and the plastic cap glued on with a material that seemed inappropriate, hard, required carving the platic cap up to get access.

Great job Mr. 300Dman, its hard to argue with success .... I could not be happier about it.....
 

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Registered
1984 300D
Joined
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5,070 Posts
It seems a little like you may not realize you and I have exchanged numerous messages in which the many factors have been addressed in this particular problem of my 617, they've been discussed, verified (at least by me) before going to ALDA adjustment as a kind of last resort. The success has been great.

As one of my astute helpers you can be proud you have offered input that has led to such good success, you are one of the few (in my experience) posters here who are rock solid.

I never found any FSM proceedure for adjusting the ALDA, your statement that observing tailpipe smoke is what the FSM tells you to do while adjusting ALDA put me over the top in proceeding with that. Based on FSM diagrams showing its function, generally, plus your warning against too much adjustment I jumped in as I have described in the prior thread ... ie the one titled OM617 too much smoke.

ON this one it did look like it could have been messed with previously. There is a metalic cup surrounding the adjust screw and its set nut with a plastic cap closure ... the surround was pushed out of shape and the plastic cap glued on with a material that seemed inappropriate, hard, required carving the platic cap up to get access.

Great job Mr. 300Dman, its hard to argue with success .... I could not be happier about it.....
I was not speaking of your case in specific and from what I have read everything you did seemed resonable; also I was speaking in gerneral.

The problem is someone who has a smoke issue may read only the first post in the thread and that person will run out and start playing with His ALDA adjustment to try to solve the smoke issue. My comments were meant to put some caution into that idea.

In your Case You were very careful with your adjustment.
I have read where others have not paid attention to where the Adjusting Screw was to begin with and they just started turning on it having no idea how much they turned it; did not get the expected results and in the few mentioned cases damaged something.

That is all I meant.
 
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