The pre chambers do need to be the right type for the pistons. The newer pistons are nearly flat top and use a pre chamber that has a rounded end on it. Thes will take either the non turbo 616 pre chambers or if you machine the head to except the turbo pre chambers then they will work fine. It is most likely with your older engine that you have pre chambers with the slanted bottom. If so you are stuck with them. Just ream them out and be happy. The newer pistons do not fit the older block as the bore is slightly differant. I would also say because you are not going for broke on hp this would be more reason to just ream the existing pre chambers. Ultimately I want about 200hp out of mine so built the head to allow that. Yes yes the pistons will melt and all will fail, but in truth I do not beleive that. I use max power very rarely but sometimes more is nice. There is a 240 out there with a 616 with dyno proven 245 hp. stock internals. So can not really say these are weak engines.

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1977 240D turbo

OP could always put in more / thicker shims when installing the "wrong" prechambers.

While I haven't heard of a 245hp OM616 there's a huge amount of videos on youtube of people putting ridiculous amounts of boost and fuel into formerly NA 617s so I don't believe that these engines will have a dramatically shorter life if run with a turbo, which seems to be the general consensus of this forum

Edit: bit slow on the post button...

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...not yet legal
1984 240TD>300TD 121,000 miles, *sold*
1977 250 parts car
1977 280> 300D - 500,000km+
1999 Hyundai Lantra 1.6

The implication being that the oil cooled pistons , the oil squirters, the beefed up bearings , etc... by people with multimillion dollar R and D departments... and a reputation to maintain.... pretty much wasted all that time and money and could have just bolted turbos to the NA engines...
One thing to keep in mind on deals like this.... those people who post those videos... if they DO have problems... often do not post that information... out of embarrassment .... a normal human emotion and response to ignoring physics and engineers advise....
One thing is clear when looking at the FSM.... where almost every major part has at least three iterations... why? Because the MB factory is ' in the feedback loop'.. when something is not working they way they want it to... based on reports from the real world... they go back in and try to improve it....

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

it isnt really a question of can it be done though. Not only have several forum members made an excellent study of this conversion plus posting their results, but the factory hasnt worried about it for 30 years, and in the meantime the Indians have produced countless turbo 240 motors.

Id love to see what internal changes they may have done, if any.

IMO the 61X series in particular is overbuilt and can handle it for low PSI stock turbos even without the special internal upgrading the turbo 617 has.

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This post brought to you by Carl's Jr.

No one said it could not be done... the question has to do with usability after it is done....
What do you mean ' the factory hasn't worried about it for 30 years' ? What is ' it ' in that sentence ?
Seems like... if you really wanted to know... it would be easy to find out what , if anything , the Indians did to those 240's ... One of our members has one.. Gurka .... I am betting they have oil cooled pistons and oi squirters...

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

To the OP,
Just DO IT! I know the turbo has piston squirters and slightly larger wrist pins etc etc, and we can go on forever about the many rather minor variations of these engines, but I personally have run my turbo 240D for about 300K. Virtually all of those miles are blasting down the highway at high power outputs. Granted there was a engine rebuild in there about 10k ago due to sand ingestion, but the engine was very high mileage when I started this little experiment, and its held up just fine. I've run boost up to around 15 psi, but normally stay around 10psi. This gives quite good performance. I can run 75 to 80 up and down the rolling hills of New Mexico with no problem. I did re-gear the car to a 3.07 rear end out of a 300d, so I'm not running out of rpm at those speeds. So far my only issue is the car running hot in the summer. I will soon put in a rad out of a 300 to solve that little problem. If you have any questions, feel free to pm me.
Cheers!
Chris

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1983 Turbocharged 240D
1982 Mazda RX-7
1974 Mazda Rotary Pickup Converted to an EV

Do you have the stock 240 oil cooler? That change alone may solve your summer cooling issues.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

47dodge has 50k on his turbo 240, and he says he loves it. He did put in 617 prechambers and exhaust valves though from what I recall. bio240D says he has 300k on his and clearly loves it.

The factory stopped building these engines in the mid 80s for cars, there has been 30 plus years of people playing with an excellent factory design that is overbuilt. Even at the time there was a rajay turbo kit available for the 240. The stock turbos are low psi and in regular use dont exceed 10-12psi, but at cruising speeds are in the 4-5psi range. Thats almost nothing compared to what people do with turbos. why is it aluminum head much weaker designed gas engines can handle a 15-30psi turbo, but a huge block of cast iron with a weak turbo is a horrible dangerous notion?

When I was looking at turbo 240ing my van, I tried to find a single reported instance of someone damaging a 240 engine with a turbo. I was unable to find that. You are right, people don't report disasters, but even then the objection seems to be "THEY said it can't be done" ect. Not it can't truly be done. I couldn't even find a "my friend did this and it blew up" type story from anyone against it.

Neither of us know what internal changes have been made on indian turbo 240 motors. Maybe email gurka and ask him to find out. However, in this thread alone we have two people with 350k between them of use who are reporting excellent results. That should answer the usability after its done question.

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This post brought to you by Carl's Jr.

LOL... wow... in this ONE THREAD we have TWO people reporting excellent results... well... that should close the argument down immediately....LOL

So the bigger picture is still what I am saying makes this a bad idea overall...
You admit that the turbos you are using as examples are low boost....

On the turbo 617 factory installation you have high boost which gives a 50 percent increase in HP... from 80 to 120. and it has longevity due to those changes from the NA engines...

or maybe you will not agree that the longevity is DUE to those changes...

that it accidentally happened and that the factory did those things unnecessarily....

So logically.... you are advocating doing a lot of labor and some expense to a NA 240 engine which we can deduce that the OUTPUT will be less than a 50 percent increase in HP.....due to the lower boost pressure compared to the factory turbo...

So how much HP are you claiming these modifications make for the 240 engine...

and why would anyone think those labor and expenses were better acquired that way... than putting a stock NA 617 into the car ?

How many HP difference is there between the turboed 616 and a NA 617 ?
5 or 10 possibly ? and it not that you then have a fast car... you are still well under 100 HP....... having taken chances ,,,, depending on what mods you do,,, with the reliability of the engine... and surely affect the potential sales price downward if you want to sell it later...... because the vast majority of the old diesel MB fans think the factory did a fine job in the first place... and are going to take off points.... or flat walk away from conversions like you describe....

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

The turbo 617 factory does not have high boost. The whole stock 617 range is 5-12psi, which is not a high boost application. People adding turbos to 240s are using the 617 turbos, across the board it is a low boost turbo setup.

I consider 350k of operational experience useful information on the matter.

People do this because you keep the fuel economy of the 240 (for what it is), combined with the power in the right places to make the 240 engine much more usable as a daily driver.

I drove a 240 NA for years, its a good highway car and would do 70 all day. Where it needed a little extra oomph was acceleration, which is where the turbo would help.

The bigger picture is what? That anyone who has done this loves it? that resale value might be different? Are you aware of how many of these cars are 1k or less semi rusted old vehicles?
basically, why the heck not? I see no downside to a fun project. As a 240 owner yourself, im not sure why this wouldnt be interesting to you as something to watch.

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This post brought to you by Carl's Jr.

I used ' high boost' only due to you calling the turbos in your examples as ' low boost'...
but the point stands with regard to the HP increase..... less than 50 percent

Why do you completely skip over my requests for you to state the empirical differences you are claiming for this type of project ? If you keep doing that... others are going to conclude you realize providing them is not good for your argument.....

"People do this because you keep the fuel e3conomy of the 240 (for what it is), combined with the power in the right places to make the 240 engine much more usable as a daily driver."--JB3

How much difference in mileage do you claim between a turbo 240 engine and a NA 617?

" Power in the right places" .... I assume you are saying the power curve is moved.. from where to where are you claiming it is moved ?

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

the 617 turbo factory is low boost. Why is this a matter of argument? compared to other turbo applications.

for example a 5.9 cummins cruising boost might be 8-10psi, and the wastegate might open in the high 20s psi.

As for your other questions, instead of scoffing and scolding, why don't you ask the two members who have posted in this thread their results? 47dodge has stated in other threads that he has improved the 240 economy with a turbo, so hes getting high 20s to low 30s with more power on hills. Whats hard to understand about this concept?

This reminds me very much of the stand you have taken against putting a 4 speed behind a 617 turbo.

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This post brought to you by Carl's Jr.

You clearly do not know the answers to the numbers which would be necessary to evaluate the potential cost benefit and risks of this kind of project....

I have been asking for you to provide those numbers so there might be a discussion based on those... as compared to me estimating them and then you arguing that I was not fair in choosing the base of comparison....

I have made my best case for this not being an economically rational way to get those few more HP available with the 616 and it stay reasonably reliable.

If you put the oil cooled pistons and squirters in... along with the turbo exhaust valves..
and oil cooler....
you have a good chance of having a reliable long lasting engine...

but the idea that the 616 is so overbuilt that it can take the turbo... set high enough to make any real difference....
without basically making it into a turbo 617 with only four cylinders impugns the entire MB R and D program.

For very near the same HP the use of a stock NA 617 does make sense.

So this is my last post in this thread.

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

Well firstly I'm probably never going to sell my w115, and secondly naturally aspirated engines are terrible, and swapping an n/a 617 into my car would not only be much more difficult and costly, the gain wouldn't be worth the cost in addition to adding probably 100-150lbs to the car

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1982 300D Turbodiesel, daily driver. Mods so far: Fram 8038 paper filter, 4 brake light mod, Gen II w126 (front) rotors/calipers, boost turned up to 12lbs, non-egr manifolds, water/methanol injection, 4-speed manual
1980 300SD Turbodiesel, project car, nearly ready to hit the street

1974 240D, New paint

Pretty much all ive asked you to do is ASK the several members who HAVE turbo 240s to post on the subject.

That seems to be too difficult, but impressive how with no actual experience of the conversion yourself, you are firmly in one camp or another.

I put together the swap for myself but never ended up altering the injection pump. I can tell you the conversion itself is prettt simple.

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This post brought to you by Carl's Jr.