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1984 300TD
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Discussion Starter #1 (Edited)
My OM617 turbo motor emits in my view excessive puffs of smoke but not steady and continuous.

It seems to be less severe when fully fully warmed up.

It seems to do so just following sitting at idle for a moment in traffic.

compression:
400
400
420
390
380

Cylinder head is freshly rebuilt.

Injectors rebuilt with monark nozzles.

It does not consume oil at a rapid pace, ie it seems to be a fuel problem

FI pump timing at 24 btdc and also at 27 btdc, the problem seems more or less the same at both those settings.

Please: if you are going to say what you think it is say why, make it make sense. So many folks on these boards "dictate" this or that without the slightest credibility through making sense, and are clearfull full of BS and thus a waste of time

A local MB shop owner says he can "adjust" the FI pump to correct this problem but will not say what he claims to "adjust". What adjustment is there on these FI pumps.

I have attended to the items in the always well informed responses by 300Dman in his response to the similar question in the post titled "Smoky OM617 despite new nozzles"

Thanks in advance......
 

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My OM617 turbo motor emits in my view excessive puffs of smoke but not steady and continuous.

It seems to be less severe when fully fully warmed up.

It seems to do so just following sitting at idle for a moment in traffic.

compression:
400
400
420
390
380

Cylinder head is freshly rebuilt.

Injectors rebuilt with monark nozzles.

It does not consume oil at a rapid pace, ie it seems to be a fuel problem

FI pump timing at 24 btdc and also at 27 btdc, the problem seems more or less the same at both those settings.

Please: if you are going to say what you think it is say why, make it make sense. So many folks on these boards "dictate" this or that without the slightest credibility through making sense, and are clearfull full of BS and thus a waste of time

A local MB shop owner says he can "adjust" the FI pump to correct this problem but will not say what he claims to "adjust". What adjustment is there on these FI pumps.

I have attended to the items in the always well informed responses by 300Dman in his response to the similar question in the post titled "Smoky OM617 despite new nozzles"

Thanks in advance......
What happened that the Cylinder Head needed to be removed?
What Color is the Smoke.

If you were to look in an old Motors Manual they would say to adjacent Cylinders with low compression could indicate a Head Gasket leak between the 2 Cylinders.

You might consider removing the Rocker Arm set that covers those 2 Cylinders so that the Valves are closed and pressurize one Cylinder with Compressed Air and remove the Glow Plug on the other Cylinder and cover the Glow Plug Hole with you Finger and see if Air Pressure is building up in the un-pressurized Cylinder; or, remove the Injector and listen for a leak.

If this is an Engine with a Turbo Charger the ALDA on top of the Fuel Injection Pump needs to be connected to a line from the Intake Manifold. More than a few people have connected a Vacuum line to it by accident.

Is this the same Engine as in the below Thread:
http://www.benzworld.org/forums/w123-e-ce-d-cd-td/1557123-300d-turbo-15k-miles-xsive-smoke.html
 

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1984 300TD
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Discussion Starter #3
ONe of the problems here is I'm green with these engines, no prior training / experience and to boot, far less naturally methodical than you clearly are. I mislead people in these posts thru my incorrect assumptions.

now I'm trying to do a more careful evaluation of oil consumption to verify my earlier perhaps hasty conclusion that it does not seem to be oil burning. I topped up the oil to the top mark and am tracking milage carefully

Reason for head exchange: bought a used 617.951 turbo motor (said to be 15K post rebuild ... no documents, its the one installed now) for install into a 300TD with a spent engine (375K mi.) ... I got the old 300TD head rebuilt for this.

Smoke color: grey, though viewing throught the rear view mirror seems iffy.

Yes it has the alda, the banjo bolt at the rear of the intake pipe is clean as a whistle.

Yes this is that same situation a year plus later. AT that time "smoking like crazy" was IP timing over 100 degrees advanced. After lots of effort, IP out and back in several times I'm sure I've got the ip timing real close.

Thanks for your suggestions.

From your Bosch training .... is there any IP adjustment at all that my affect the fuel mixture? My understanding: smoke from fuel problem is too much fuel for the engine load ie rpm.

A local MB mechanic says he can "adjust" it. But he won't say adjust what. "Trade secret" he says. He's a jerk and not just because of that.
 

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ONe of the problems here is I'm green with these engines, no prior training / experience and to boot, far less naturally methodical than you clearly are. I mislead people in these posts thru my incorrect assumptions.

now I'm trying to do a more careful evaluation of oil consumption to verify my earlier perhaps hasty conclusion that it does not seem to be oil burning. I topped up the oil to the top mark and am tracking milage carefully

Reason for head exchange: bought a used 617.951 turbo motor (said to be 15K post rebuild ... no documents, its the one installed now) for install into a 300TD with a spent engine (375K mi.) ... I got the old 300TD head rebuilt for this.

Smoke color: grey, though viewing throught the rear view mirror seems iffy.


Yes it has the alda, the banjo bolt at the rear of the intake pipe is clean as a whistle.

Yes this is that same situation a year plus later. AT that time "smoking like crazy" was IP timing over 100 degrees advanced. After lots of effort, IP out and back in several times I'm sure I've got the ip timing real close.

Thanks for your suggestions.

From your Bosch training .... is there any IP adjustment at all that my affect the fuel mixture? My understanding: smoke from fuel problem is too much fuel for the engine load ie rpm.

A local MB mechanic says he can "adjust" it. But he won't say adjust what. "Trade secret" he says. He's a jerk and not just because of that.
The ALDA can be adjusted but there is a difference between adjusting it the way the Manual wants and just turning the screw to see what happens.
The screw should only be turned in tiny amounts as it is possible to Crack the inards of the ALDA.

I had Gray Smoke all of the Time when the Piston Rings were Stuck due to the Car Sitting one year without driving and when I did drive it took me 6 months to realize the Thermstat was opening too soon and it was never reaching the proper Temp.

I skeptically dumped in a 1/4 cup of Marvel Mystrey Oil into the Cylinders and let it soak for one Week. I rotated the Engine and repeated the above but was only able to let it soak for an additional 3 dayse and had to get the Car Going.
I changed the Oil and took it for a hard drive on the Freeway. I worked but took about 3 days of driving for the gray Smoke to clear up.

You never commented on the erattic compression reading. If the Engine had been a rebuilt one the compression of the Cylinders would be closer to each other. There is some reason for that not being so.
 

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Discussion Starter #5
From what I can see in the FSM the variance in compression is within MB spec, ie 3 bar or 43.5 psi. The rebuild could be real, after all the compression isn't low, its mid range normal. My experience is not enough to comment at all. Regardless I have no proof of anything about the rebuild.

My manual says zip about how to adjust ALDA, nothing. They say (wrongly) that at higher altitude higher atmosopheric pressure ( it is lower at higher altitude) expands the aneroid capsule ( that lower pressure would do one would think) thus decreases fuel injected. Something seems lost in translation.

ONe possibility complicating my problem is this vehicle now has a manual transmission and the changeover valve may no longer be getting an electrical signal from the transmission that is relevent, the last item mentioned in 09-450 of my FSM motor section. The last section in the ALDA functional explanation in the FSM refers to limiting fuel feed under high stress above 2000 rpm and low boost under .3 bar. It refers to the changeover valve positively venting the aneroid capsule to reduce fuel feed.

Vacuum transducer switchover valve also can send a signal to the overload relief valve. Gotta hand it to these krauts.

I'll post something if this electrical thing ends up pertinent. Its on page 109/1 of the 300TD wiring diagram for overload protection but I have not found the component locaton for the vacuum transducer switchover valve. Front Right engine compartment next to the SLS fluid reservoir I suspect with elect ( to ?) and vacuum lines to the left engine area.
 

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The ALDA does not need to be adjusted according to the FSM. The transmission overload protection was not used on the later models.

The vacuum transducer switchover valve only switches between high vacuum and low vacuum depending on engine temperature, to give more smooth shifts when the engine and transmission is cold. It can only be found on 1985 models.
 

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From what I can see in the FSM the variance in compression is within MB spec, ie 3 bar or 43.5 psi. The rebuild could be real, after all the compression isn't low, its mid range normal. My experience is not enough to comment at all. Regardless I have no proof of anything about the rebuild.

My manual says zip about how to adjust ALDA, nothing. They say (wrongly) that at higher altitude higher atmosopheric pressure ( it is lower at higher altitude) expands the aneroid capsule ( that lower pressure would do one would think) thus decreases fuel injected. Something seems lost in translation.

ONe possibility complicating my problem is this vehicle now has a manual transmission and the changeover valve may no longer be getting an electrical signal from the transmission that is relevent, the last item mentioned in 09-450 of my FSM motor section. The last section in the ALDA functional explanation in the FSM refers to limiting fuel feed under high stress above 2000 rpm and low boost under .3 bar. It refers to the changeover valve positively venting the aneroid capsule to reduce fuel feed.

Vacuum transducer switchover valve also can send a signal to the overload relief valve. Gotta hand it to these krauts.

I'll post something if this electrical thing ends up pertinent. Its on page 109/1 of the 300TD wiring diagram for overload protection but I have not found the component locaton for the vacuum transducer switchover valve. Front Right engine compartment next to the SLS fluid reservoir I suspect with elect ( to ?) and vacuum lines to the left engine area.
If you have Manual Transmission you ought to see if you can find out where the Hoses should be routed on a Manual. I am guessing that on a Manual the Hose from the Intake Manifold to the ALDA has no valve in it.
 

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The ALDA does not need to be adjusted according to the FSM. The transmission overload protection was not used on the later models.

The vacuum transducer switchover valve only switches between high vacuum and low vacuum depending on engine temperature, to give more smooth shifts when the engine and transmission is cold. It can only be found on 1985 models.
There is a procedure buried somewhere in the Factory Service Manual that has how to adjust the ADLA. It is just that in the FSM many things are cryptically labeled and not in the sections you would think they are in.

I also did not mean to imply that the ADLA was something like the Valves that need periodic adjustment.
 

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If you have Manual Transmission you ought to see if you can find out where the Hoses should be routed on a Manual. I am guessing that on a Manual the Hose from the Intake Manifold to the ALDA has no valve in it.
Why should that be? The protection valve is to protect against overload in general. Unless somebody removed the valve it will still be there.

There is a procedure buried somewhere in the Factory Service Manual that has how to adjust the ADLA. It is just that in the FSM many things are cryptically labeled and not in the sections you would think they are in.
I'd be interested to see that procedure.
 

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Discussion Starter #10 (Edited)
The ALDA does not need to be adjusted according to the FSM. The transmission overload protection was not used on the later models.

The vacuum transducer switchover valve only switches between high vacuum and low vacuum depending on engine temperature, to give more smooth shifts when the engine and transmission is cold. It can only be found on 1985 models.
Mr. Govert ... thanks for your input. Its so nice to have well informed and skilled communicators helping .... you and 300Dman are both the real McCoy (an american euphamism for "genuine article") in this way.

Yes 300Dmans observation about FSM files seeming to be obscurely almost hidden or at least hard to find is something I tangle with often.

MB never imported W123 300D OM617 vehicles into the states with manual transmissions, automatic only. Except for the occasional vehicle brought over by americans purchasing vehicles in Europe and bringing them back here, we don't have factory vehicles to look at. All our after market parts searches exclude manual transmission references and our FSM manuals contain no schematics for those Euro specific vehicles with manual trans. My 240D has an AlDA but with no air line to it to modify its function .... presumably it is modified by altitude only.

I'm stumbling around with the smoke issue. So far experimental ALDA adjustments, first a one eighth turn out (counterclockwise) then a one eighth turn in (both references are from the baseline position it was in) have not resulted in clear discernable differences. My up front guess is that the smoke is from too much fuel and that counterclockwise, unless threads on the adjustment shaft are reversed, with decrease fuel. I do have in initial impression the first adjustment may have decrease smoke just a little and the second adjustment may have made it a bit worse, so I will return to trying an adjustment in the counterclockwise direction again going two eighths from baseline.

If you ever do come across relevant euro FSM files showing electrical schematics or ALDA schematics with a functional description of the manual transmission version of ALDA function .... I would be so grateful if you could fire that file to me by email. I think the files can be saved as pdf filse and can be emailed.....

[email protected].

Thanks for you input .... I do need help!
 

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Discussion Starter #11
There is a procedure buried somewhere in the Factory Service Manual that has how to adjust the ADLA. It is just that in the FSM many things are cryptically labeled and not in the sections you would think they are in.

I also did not mean to imply that the ADLA was something like the Valves that need periodic adjustment.
Yes things remain hard to find for me, even after finding them but forgetting how at times.

I did experiment with ALDA adjustments described in a response to Govert. I have this memory that you have had some training from Bosch....

Can you comment from what you learned at all about the ALDA adjustment in any specific. way??

Thanks again for your help ....
 

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The turbodiesel w123 300D wasn't sold with a manual transmission in Europe either. The ones you see with a manual are later conversions.

The US version of the 240D had an ADA, which should not have anything connected to it. It only reduces fuel at altitude (altitudes are higher in North America compared to Europe, making such a device useful), so your presumption is correct.

The function of the ALDA does not depend on the transmission. It responds to air pressure in the intake manifold. That air pressure is depended upon ambient air pressure and the turbo. That air pressure determines the amount of fuel that can be injected, basically more air pressure = more fuel.

When does the smoke occur? At full load or at partial load too? What is the fuel consumption? What is the 0-60 mph performance?

The mixture of a diesel engine is always lean, i.e. there is always more air than fuel. Even at full load the mixture is still lean. You can adjust the pump so that it injects more fuel than can be burnt in a cylinder, but it highly unlikely that is the case. Normally an IP is adjusted during production of the pump and those adjustments stay OK. Only if somebody tampers with it, like unscrewing the two rows of nuts either side of the pipe connections, something can go wrong with the adjustments.

The average MB dealer doesn't adjust the IP or he shouldn't do it, it should be left to a qualified diesel workshop, which has the testing equipment.

So why does it smoke? Compression is OK, was the compression test done with a warm engine or a cold one?.

Most likely is IP timing IMHO. Some other possibilities are:
- valve stem seals and valve rotators weren't replaced.
- Incorrect parts were used for the engine rebuilt, such as the wrong pre-chambers.
- Engine not correctly put together, who put the engine together? Did they follow the FSM?
 

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Discussion Starter #13
The turbodiesel w123 300D wasn't sold with a manual transmission in Europe either. The ones you see with a manual are later conversions.

The US version of the 240D had an ADA, which should not have anything connected to it. It only reduces fuel at altitude (altitudes are higher in North America compared to Europe, making such a device useful), so your presumption is correct.

The function of the ALDA does not depend on the transmission. It responds to air pressure in the intake manifold. That air pressure is depended upon ambient air pressure and the turbo. That air pressure determines the amount of fuel that can be injected, basically more air pressure = more fuel.

When does the smoke occur? At full load or at partial load too? What is the fuel consumption? What is the 0-60 mph performance?

The mixture of a diesel engine is always lean, i.e. there is always more air than fuel. Even at full load the mixture is still lean. You can adjust the pump so that it injects more fuel than can be burnt in a cylinder, but it highly unlikely that is the case. Normally an IP is adjusted during production of the pump and those adjustments stay OK. Only if somebody tampers with it, like unscrewing the two rows of nuts either side of the pipe connections, something can go wrong with the adjustments.

The average MB dealer doesn't adjust the IP or he shouldn't do it, it should be left to a qualified diesel workshop, which has the testing equipment.

So why does it smoke? Compression is OK, was the compression test done with a warm engine or a cold one?.

Most likely is IP timing IMHO. Some other possibilities are:
- valve stem seals and valve rotators weren't replaced.
- Incorrect parts were used for the engine rebuilt, such as the wrong pre-chambers.
- Engine not correctly put together, who put the engine together? Did they follow the FSM?
I'm surprised to hear about no manual trannys in Europe. The website I use to find part numbers (based out of Russia) shows exploded four and 5 speed transmissions for these 300D models, but again I'm full of assumptions here.

It occurs at high load more than low, though I'm depending on rear view mirror viewing for assesment, so its a glance at a time. I think it does smoke at low load ie cruising with normal flow of traffic too but less severe. It seems to be worse after a moment idle then accelerating into traffic flow, worse under high load accelerating on the freeway.

Fuel consumption: good question. I will take a crack at methodical evaluation of this question and compare the result with factory specifications.

Same with zero to 60 performance. I will try to obtain numbers.

Re: prior tampering with ALDA: looks like that has been done. The metalic surround at/around the ALDA adjustment screw is bent out of round a little bit, the plastic cap glued on with material that seemed inappropriate, very hard, leaving plastic cap fragments stuck down around the 10mm lock nut.

Compression check was done on a warm engine.

You are not the first well informed person who has stated IP timing is the most likely problem. After much tribulation I feel I have learned that proceedure and finally got drip drip very close to 1/sec. That seems to be a very precise spot. I will go back and run it again.

The head was rebuilt at a local MB shop that seems like good one, its a MB exclusively and run by a Czech guy. He became a bit defensive when I asked him about valve seals as related to this smoke.

Engine assembly: I bought it used, supposedly rebuilt 15K miles prior to me getting it, then installed the newly rebuilt cylinder head used on the 300TD wagon. There is no verification at all of what or who did this work. .... I assume you refer to use of pistons and cylinder liners that no longer meet MB specifications.

Thanks Govert, I'll follow up on your excellent suggestions.
 

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The manual gearboxes you see are for the normal, naturally-aspired 300D. In Europe the N/A 300D was available until 1985. The turbodiesel engine was only available in the T (wagon) in Europe and only with a automatic gearbox.

At idle there isn't enough pressure to press the piston rings against the cylinder wall, so more oil will get past the rings. When you accelerate, that oil will burn and will cause smoke. This is in a way normal, depending on how much oil will get past the rings. If the rings are bad or if the pistons and/or cylinder liners are out of specs, the engine will consume oil all the time. Do you know how much oil the engine is consuming? Did you try the Marvel Mystery Oil treatment 300DMan described?

Bad valve stem seals usually cause high oil consumption with gas engines, because of the intake manifold vacuum. It is less of a problem with diesel engines, but if the engine head was overhauled, I would assume that valve stem seals, rotocaps (and perhaps the valve springs) would be replaced, as those parts aren't exactly expensive, certainly not compared to the total overhaul cost. And removing and putting the seals back can damage the seals, if you don't cover the thread of the valve stems. Why would your mechanic be defensive about it?

Diesel smoke can be caused by:
1. diesel injected too late in the cycle: the diesel doesn't get heated enough to evaporate and burn.
2. not enough air: air filter plugged (is rare)
3. fuel pressure of the low-pressure area too low: can be caused by air in the fuel line or fuel pressure relief valve opening too soon. Usually the engine will run rough too if this is the case.
4. not enough compression, so that the temperature is too low for all the diesel to burn. This can be caused by the wrong valve clearance or by wear on pistons or cylinders
5. timing chain elongated so that the compression does not occur at the correct moment.
6. dirty injectors and/or prechamber.

If we are to assume that the engine is OK because it has been recently overhauled, than only the IP timing can cause the smoke, that is why I suggested the IP timing. Can you describe the steps that you have taken regarding IP timing or did you already wrote about it (I think I remember reading about it)?
 

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Yes things remain hard to find for me, even after finding them but forgetting how at times.

I did experiment with ALDA adjustments described in a response to Govert. I have this memory that you have had some training from Bosch....

Can you comment from what you learned at all about the ALDA adjustment in any specific. way??

Thanks again for your help ....
I worked in a Fuel Injection Shop up until 1980. So the Fuel Injection Pump in question was not around then. The only official Factory Bosch Training I have is on a Fuel Injection pump that predated the Bosch VE Pump; the EPVA Fuel Injection Pump.
The rest was simply doing what my Boss told me to do.

Setting the ALDA is in the Factory Service Manual. I can't remember the Specific Details but it calls for you to get the Engine up to operating temp, apply the Parking Brake, step on the Brake, put it into one of the Gears (Automatic Transmission, I don't remember which Gear) and keekping pressure on the Pedal you rev the Engine to Xrpms (don't remember that either) and observe the Tail Pipe Smoke.

It is a short duration test and there is a specified Max time limit you are allowed to do the test with the Engine revved up.

I have never done that test or even turned the adjustin screw on my ALDA as I am happy with it the way it is and it only puts out some gray smoke when I step hard onto the Accelerator Pedal. So for Me that is perfect.

It is not unknow for the Capusels inside the ALDA to crack. Not made to operate on Vacuum they should hold Vacuum if you connected to a hand pumped Vacuum Tester.
 

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Discussion Starter #16
That is interesting, observing tail pipe smoke is what one observes while adjusting ALDA screw.

I recall another (can't remember which) diesel engine adjustment that similarly, set the parking brake, put it in drive or one of the forward trans modes then hit the accelerator up to 4K rpm briefly. It was for boost pressure check I think.

Following your good council regarding small adjustments only I tried one eighth turn adjustments of the screw. First counter clockwise (if threads are not reversed that should reduce fuel delivered by extending the connector shaft downward) then clockwise one eighth from baseline. There may have been improvment with the first trial and slight worse with the second. Then I went two eighths counter clockwise from baseline, made a 70 mi. run yesterday and lo and behold I think there is improvement. I'll give it at least one more day of observation then may try another eighth in the same direction.
 

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Discussion Starter #17
The manual gearboxes you see are for the normal, naturally-aspired 300D. In Europe the N/A 300D was available until 1985. The turbodiesel engine was only available in the T (wagon) in Europe and only with a automatic gearbox.

At idle there isn't enough pressure to press the piston rings against the cylinder wall, so more oil will get past the rings. When you accelerate, that oil will burn and will cause smoke. This is in a way normal, depending on how much oil will get past the rings. If the rings are bad or if the pistons and/or cylinder liners are out of specs, the engine will consume oil all the time. Do you know how much oil the engine is consuming? Did you try the Marvel Mystery Oil treatment 300DMan described?

Bad valve stem seals usually cause high oil consumption with gas engines, because of the intake manifold vacuum. It is less of a problem with diesel engines, but if the engine head was overhauled, I would assume that valve stem seals, rotocaps (and perhaps the valve springs) would be replaced, as those parts aren't exactly expensive, certainly not compared to the total overhaul cost. And removing and putting the seals back can damage the seals, if you don't cover the thread of the valve stems. Why would your mechanic be defensive about it?

Diesel smoke can be caused by:
1. diesel injected too late in the cycle: the diesel doesn't get heated enough to evaporate and burn.
2. not enough air: air filter plugged (is rare)
3. fuel pressure of the low-pressure area too low: can be caused by air in the fuel line or fuel pressure relief valve opening too soon. Usually the engine will run rough too if this is the case.
4. not enough compression, so that the temperature is too low for all the diesel to burn. This can be caused by the wrong valve clearance or by wear on pistons or cylinders
5. timing chain elongated so that the compression does not occur at the correct moment.
6. dirty injectors and/or prechamber.

If we are to assume that the engine is OK because it has been recently overhauled, than only the IP timing can cause the smoke, that is why I suggested the IP timing. Can you describe the steps that you have taken regarding IP timing or did you already wrote about it (I think I remember reading about it)?
A trial of one eighth rotation increments of ALDA screw seems to have an effect. All these references are from the baseline where I found the screw before any adjustments. First counterclockwise (presumably reducing fuel) showed some possible improvement, then one eighth clockwise I observe possibly a bit worse. Then back to counterclockwise, two eights rotation from baseline then I went on a 70mi. run and at that setting. Here I see greater improvement so this if very hopeful. I may go one more eighth rotation counter clockwise after more observation at two one eighth rotation counter clockwise its currently at.

I am currently doing a more methodical assesment of oil consumption, my initial impression is consumption is quite low. I am prone to jumping to conclusions so must learn some things about methodical information collecting and taking notes especially if requesting the kindness of others for information. I topped up the oil and am tracking milage.

Yes I did run the MM oil soak according to 300Dmans prescription over a year ago when the engine was first runnig after the head rebuild / installation.

The MB shop keeper who rebuilt the head probably felt I was questioning his integrity by even asking about valve stem seals after the head rebuild, I now know its so routine. It may not be so clear to him that I am as green (inexperienced, under informed) as I am. He's Czech I think but seems to like taking on the hideous vibe of the worst type of German. Arrogant and putting people down is a way of life.

1- timing currently set at 27btdc (Forced Induction suggested this setting) ... it does have a satisfying growl of a sound. Because you are the second well informed person to declare this it the likely problem I will be running through this again. Using the the 1 drip/sec method: it is exacting and I struggled to getting the IP into the exact position for 1/ sec. VEry small movements go from free flow to zero flow.
2- air filter is new
3- I made a fuel pressure gauge using spare connectors and adding a T piece connected to a cheap gauge. Don't remember the number but is was normal. I also measured the natural length of the spring in the pressure relief fitting in the R side of IP on the return to tank circuit. It was short a bit, FSM says simpy stretch it out to 27mm if I remember right.
4- compression seems to be within MB spec.
5- timing chain shows zero stretch.
6- injectors got rebuilt with new monark nozzles last year. Smoothed it out nice.

IP has been out and back in several times. I found a way to get the locking/brace bolt at the bottom rear of the IP back on without the filter tower off.
 

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Discussion Starter #18 (Edited)
I estimate the smoke was reduced at least 50% by the 90 degree counter clockwise ALDA screw adjustment.

Also I now notice the temp gauge on the dash does not rise anywhere near the 80C normal running temp. Could be sender, electrical or thermostat stuck or missing. As Govert notes, its gotta get hot for normal combustion.

Next day:
Additional ALDA screw rotation to total 180 degrees counter clockwise and smoke is reduced to 10% of the former amount, and then only with the pedal to the metal. IP timing 27 btdc. Its got that om617 satisfying growl.

Good work boys.

Dr. Govert I'm taking up a collection to send you to Tahiti for at least six months. Beer and bare breased women for you, all you want, sounds like you could use a little rest.
 
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