I have a slightly tired but, well loved 450 SLC here in the UK and I'm getting to the point where I'm going to have to pump a reasonable amount of cash into her to get her back to her former glory.

I'd be more than happy to do that if I could afford to use her more or even, get her to a position where I could afford to use her as my daily driver.
I won't bore you with the cost of fuel here in the UK but lets just say each time I have to fill up a hire car in the US, it's depressingly cheap!

Logically the most sensible way to achieve this is to convert to diesel and I have I spent the last two nights reading Mach4's inspirational topic.

However, and I may be wrong as I have very little MB knowledge at this point, the 300D unit used in the thread is the turbocharged unit which does seem a very common fitment in US cars but, it doesn't seem that common here in the UK, unless I'm missing something?

The normally aspirated 300D engine does seem quite common but I have my concerns as to whether a N/A lump pushing out around 125hp would have enough poke to get the SLC moving? I'm not after speed, I'd like to be able to sit on the motorway at 70mph and would the N/A have a 0-60 time of around a week?

I've looked at the other options mentioned here and as this is a US based site, a lot of the American vehicle engine options don't exist here in the UK so they're out of the running.

The other option is to find a Mercedes diesel engine that physically fits and then work everything out from there. As mentioned, I don't know a lot about the Marque, I bought the car as I just love it, nothing specifically to do with being a Mercedes fan, so when people start quoting various engine and gearbox codes I start to struggle!

I have heard people mention in various threads about Mercedes using the same block in many engines. If that is the case, what is the last model/variant that could utilise the SLC engine frame?

This would help me identify a suitable donor vehicle and then I could start working out all the potential issues associated with it. I'm guessing as the models progressed they became more reliant on electronics so that would obviously be an issue to overcome and although I personally hate electronics with a passion, I have a couple of colleagues 'in the know' who could probably help resolve those issues. Also, I'd be looking at buying a complete donor vehicle so if required, I would have access to all the looms/controllers etc.

I'm open to any suggestions or advice. I love the 300D idea as it appears the far simplest method (now someone has done all the hard research work!) but think I'd struggle to find a reasonably priced 300D turbo unit here in the UK.

Cheers!

Interesting that turbos are not common in UK. I recall same was true in South Africa where they actually may have built the RHD cars.

In Europe, did they not have turbos? Would imagine that going from LHD to RHD wouldn't impact engine swap too much.

By the way, you could probably buy an '85 300D like mine over here for US$2or3k. Plus shipping. Finding one with a good engine would be next challenge. Mine is not for sale, but engine only has about 120k km since rebuild.

Maybe a conversion to electric is what we will have to think about as fuel prices rise?

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

"300D" could mean at least 3 different engines

I would recommend you swap an OM606 rather than a 617. Far, far better engine and I believe you can get the turbo version (177hp stock?) rather easily - the turbo 617 was never sold in RHD countries...Nothing wrong with an OM617 but NA was 80 or 88hp and turbo 110-125.

OM606 can be made entirely mechanical if swapping to manual gearbox and an injection pump from a OM603.

OM606s are also able to handle 500hp+ on stock internals if you wanted to go down that route (don't think you do?)

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD

While your recommendation makes sense from a performance standpoint, it is at least an order of magnitude more difficult.

The 107 uses the same front subframe as the 114/115, meaning that it is essentially a bolt in proposition if you use the engine support arms from those and an oil pan from an early 617 without the waffle support structures. You don't even need to modify the drive train.

On the otherhand if you use the 603/606 engines you have to either do some SERIOUS subframe surgery or fabricate a new oil sump. Since the OP lives in England there is the little matter of a MOT inspection which prohibits modifications to structural members. Fabrication of engine supports and engine mounts are also required. If you go with the 606 and the 722.6 there is the little matter of the transmission controller - sure stand alone controllers are available, as are stand alone controllers for the electronic IP but that's expensive and a pain to configure/program. To make the engine fit it requires changing the angle which then makes it necessary to fabricate a whole new drive train. Fitment issues to the tunnel are also known to be problematic. Oh and the 606 turbo has an intercooler which has to be fitted somehow.

....an on it goes.

The 617 is very nearly a bolt in proposition.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

OM617's aren't very common in the UK, as they are all in W123's which are either rusted away or worth serious money.

OM603, OM602 and OM601's are fairly common in 190D's and W124 250D's and 300D's, but they are very rare in turbo form. And the OM603 without a turbo only puts out 113hp.

OM606, OM605 and OM604's are more common (in W202's and W210's) and often come with turbos, so might be a better choice.

Or if you get really brave there are LOADS of OM613, OM612 and OM611's around. They are CDI engines and will have loads of power, but are very electronic.

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1991 W124 250D - 130k Miles

You make a very good point which I forgot about, but I swear I saw a guy from the UK do this very swap with a 606? Think the owner is even on this forum...
Also 606 engines swap parts such as sumps with the later engines so I'm sure a sump could be found that was at the right place to clear things.
Even still, modifying (rewelding etc) a sump would be easier than modifying the crossmember.

I don't think swapping a NA OM617 is worthwhile and putting a turbo on one like I have would probably have legal hoops similar to what I have to do down here (on top of a diesel swap)...a turbo 617 is probably harder to find than getting a sump that makes a 606 clear?

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD

Aha, checked your thread Mach just below this one, so for OP's sake

Not "another" diesel 107!!

606 in a 107 with a custom sump.

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD

First off... the NA 617 is not 125 hp... is is around 90 in euro form. A stock 450 would have a 2.47 rear diff ratio, so while you could keep it for better fuel economy, the motor would have a hard time accelerating from a stop. You could swap the diff from the donor car, and have fine acceleration, but you would need to change the speedometer gearing, or show 100 mph, at 60 actual....

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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!

Cheers for the info. However, do these engines fit in without too much effort?
Although I'm not keen on entering the world of electronics, if needs be, I'll consider it but, the engine has got to go in on the subframe.

Also, the other point worth mentioning is the fact that I want to keep the car as an auto as I notice a lot of the conversions also change the gearbox to a manual which doesn't interest me.

I forgot to mention, things like the sump fabrication isn't an issue but, I want the vehicle to use original engine mounts etc, nothing fabricated.

Just been trying to do a bit of research into buying a complete vehicle to buy as the donor, especially if electronics are involved as it in theory gives me everything I'll need, (I'll probably buy an accident damaged vehicle) but, I'm still trying to establish what was the last vehicle produced with a Diesel engine that will physically fit the subframe, ignoring sumps, etc?

Read this thread - The Making of Samson Worlds First V-12 107 - Mercedes-Benz Forum.....not that you're going to install a V12, but the portions related to getting the electronics to work will prove instructive. This is why people generally go with manual transmissions or go with a third party controller.

If you want a very close to bolt-in conversion, import a 617 turbo and 722.3 transmission (and a few special bits like the SD oil filter housing), and if you want a very complex, but doable, conversion, go with the 606...both have been done and are documented.

Not to muddy the waters, but if I were on your side of the pond, I would spend some time researching the possibility of installing a Subaru boxer diesel. I find those rather interesting but have no idea whatever it would be feasible.

Have you contacted Druk?

__________________
Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

617.912 with corresponding transmission and diff (3.46 I think) should be the trick. Then spend a good amount on it getting the timing chain replaced, injection pump calibrated, injectors serviced and pump set up properly. Realize there is going to be a good amount of frustration with the vacuum system (adding it on the ignition switch and such). It will not be fast, but able to do what you want on the highway and still accelerate off the line.
Going with a newer engine is going to be death of the project, it will be forever in the making. Keep it simple and use parts that are known to fit and reasonably easy to find. When you start going with stand alone system and fabrication you loose any sort of built in reliability, breaking down who is going to fix it if you cannot?

With a one percent difference (1%) in the price of diesel vs. petrol, and diesel being the greater, there will not be sufficient savings in reduced fuel consumption to ever amortize the marginal cost of converting to diesel power over converting to a more modern petrol powerplant of 125HP or greater.

Diesel > 113.34 p/L
Petrol > 112.07 p/L

this is the most salient post. there's not much economic about it, OP just wants a project!

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'77 240D, 504H, OM617.952, etc.