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23K views 84 replies 28 participants last post by  jgrimm 
#1 ·
Not sure if this is the correct section, but Ill post here since it gets the most hits.

Just want to see how many people are actually interested in such a vehicle.

I have a planned build ready to roll with a very affordable pricetag. The reason I ask; I get bored with things rather quickly and want to make sure I could get my moneys worth out of it if my automobile A-D-D kicks in. If I get bored, Ill sell it and buy a wrangler. (I may just end up buying a wrangler instead of building this beast.)

Specs:
Mercedes-Benz OM617A I-5 TurboDiesel, fully mechanical, nothing to break, its bulletproof. Plenty of torque. 24MPG highway. Will easily last 500k miles if maintained. Parts are everywhere for it (worldwide). And the most compatible engine for use with WVO or BioDiesel.

6.5" Lift custom installed by Galloways 4x4 center.

Stock AX-15 5-speed Trans

Stock Tcase.

May need 410 gears depending on tire size.


Price complete would more than likely be around 5k USD or less.


Any interests?
-Grimm
 
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#4 ·
thumbs up for Galloways. i grew up right by there and i stop by every time im at uwharrie
 
#5 ·
I'd wheel it.

Seriously, a diesel Jeep is my dream come true. I love diesel power but I hate common rail, but it's a necessary evil if you want any Jeep offerings in diesel on this side of the pond.

I've thought about getting an old diesel from a Benz and seeing what it would take to drop into an XJ.
 
#6 ·
Would love to swap a diesel into my jeep....

Clean diesel is the fuel of the future!
 
#9 ·
Glad you guys have an interest in this idea!

The swap isnt too bad at all from my research so far. I can use the AX-15, as I can get the OM617 to bolt right up to it; all that must be fabricated are engine mounts and a few smaller things like joining the power steering linkage ends together. The Vickers power-steering pump on the OM617 should be plenty sufficient for the XJ, and for nearly any vehicle it could ever be swapped into. And also, the vacuum provided by the OM617 should be enough to drive any vac powered accessories as well.

The only issue is oil pan clearance. You will need a small lift kit for the oil pan to clear the front diff. Or you can modify the pan a bit. Most of us on here have lifts, so that's really no big deal.

Also, the swap wont work in the Peugeot equipped Wranglers and Cherokees at this time. Sorry all you 4.2 guys ;)

I can do the swap on any AX-15 equipped Wranglers as well.

If built, this is going to be a R&D car for a BioDiesel lab, my daily driver, and my off-road machine, all while getting at least 20MPG.

Anyhow, I am selling this Nissan I have before I can go farther. And I found a Wrangler TJ for 3500 I am going to look at as well before I decide.

Cheers,
-Grimm
 
#11 ·
Specs:
Mercedes-Benz OM617A I-5 TurboDiesel, fully mechanical, nothing to break, its bulletproof. Plenty of torque. 24MPG highway. Will easily last 500k miles if maintained. Parts are everywhere for it (worldwide). And the most compatible engine for use with WVO or BioDiesel.

Price complete would more than likely be around 5k USD or less.
-Grimm
My other car is a 83 Mercedes 300SD with the 617 turbo engine. I think you are a little optimistic about nothing to break and bulletproof but they are very durable engines and with proper care can run 500k and more. They have about 123 HP but a lot of torque.
I always thought this would be a good conversion.
 
#12 ·
Definitely is a great swap.

Eh, maybe a little bit optimistic, but my friend has 4 of them. He has put over 400k miles on one, 250k on the other, and 700k on the oldest. Never had an ounce of trouble aside from regular maintenance. His kids still drive the one with 700k (probably about to hit 750k by now). He drives alottttt due to work and so does his wife/kids.

Amazing little engines.

EDIT:
Actually, he did have trouble out of the 700k at one time, I think it was an injector pump. Bought one for like 200$ from Craigslist if I remember correctly.

Also, what I meant by "price complete" in the first post was a complete jeep turnkey with a clean title and decent body. The conversion is muchhhhhhh cheaper if you already have a jeep. That price was just my estimate to build a complete trail-ready Cherokee exactly like I want and to my specs.
 
#14 ·
A Cummins 4BT would be awesome. I love the sound of those little engines.

But to be honest, the Cummins doesn't seem to be worth the hassle. More work involved and also, incredibly expensive. A decent 4BT costs around 2k-4k these days; much more expensive than the Benz. I can get a complete running car; a 300d (Turbo OM617A) for anywhere between 300-800$ and most of the time they have transmission issues/no problems whatsoever with the engine. Many of them have around 200k miles, which in OM617 miles is like 30k on a regular engine.

Also, the Mercedes diesels are so cheap that for the price of the cummins, you could buy like 3 of them, scrap the 300d's and still have a assload of money left over for lift kit and extra goodies. Thats my kind of engine!

I reallyyyy would love to put one of these in a 1995 Grand Cherokee, but they didnt come with the 5-speed AX-15 as an option. A black one with 6.5 inches of lift, 33's, all blacked out, deep window tints, roof rack, Navigation, Mini fridge, Road armour bumpers, HID hella's.... Dream Jeep... Haha
 
#17 ·
Thats odd. Here in NC, you just have to pass safety inspection on vehicles older than 1996 (1995 and below)

OBD-II started in 1996.

What kind of tests must your vehicle pass in NY?
 
#16 ·
some thoughts...

just throwing my $.02 into the thread...

i too have long thought diesel powered XJ would be great!

i read a blog a long time ago about a VW jetta mid-80's engine going into a ZJ, seemed mostly straightforward and not terribly different than the OP's idea.

some things i would consider:

first, would you be able to pass any inspection for your state? would i ever move to a state that has inspection that would potentially not allow it? i live in TX, and diesels here only require a basic safety inspection, and have a different tax rate for registration of the vehicle (my wife's car is a TDI passat, and i had a ram CTD before my XJ) so what would be the considerations? could i somehow get the registration changed? obviously 'at the inspection station' the inspector would say 'yeah it's a diesel now' and probably give me a sticker, but what about when i went to get tags/registration? that office is pretty tough on whether or not your inspection papers are legit. anyways, just some thoughts on that matter.

secondly, motor choice! is the 300D engine mentioned above going to deliver 'real-world' performance similar to what it does in it's original chassis? one on hand i would say yes, and another no. say if you do a minimal JY/BB (ZJ V8 coils and BP rear for about 2" lift) and the oil pan adequately clears i would argue you'd get close to the same MPG/perf numbers seen in the original car, however i'd argue it would 'feel' grossly underpowered compared to the 4.0L. even more so for going with +3" lift/+30" tires (even considering appropriate re-gear) it would likely feel wayy underpowered.

what about that isuzu NPR diesel commonly found in box vans? i don't know enough about them to say much. if the engine/associated hardware has a decent power/weight ratio and appropriate physical dimensions it could be a good choice.

and onto the 4BT: it's a 6BT less two cylinders, which unfortunately means even though it's slightly smaller end to end, it still weighs twice as much as the 4.0L removed, not to mention the top to bottom size difference...it's HUGE and HEAVY.

i would recommend reading the various links and articles found here: Novak Conversions - General Engine Conversion Options

weights and physical dimensions considered, the novak articles make a sound argument in favor of the LS1 GM V8 against pretty much anything else for mileage/efficiency
 
#18 ·
just throwing my $.02 into the thread...

i too have long thought diesel powered XJ would be great!

i read a blog a long time ago about a VW jetta mid-80's engine going into a ZJ, seemed mostly straightforward and not terribly different than the OP's idea.

some things i would consider:

first, would you be able to pass any inspection for your state? would i ever move to a state that has inspection that would potentially not allow it? i live in TX, and diesels here only require a basic safety inspection, and have a different tax rate for registration of the vehicle (my wife's car is a TDI passat, and i had a ram CTD before my XJ) so what would be the considerations? could i somehow get the registration changed? obviously 'at the inspection station' the inspector would say 'yeah it's a diesel now' and probably give me a sticker, but what about when i went to get tags/registration? that office is pretty tough on whether or not your inspection papers are legit. anyways, just some thoughts on that matter.

secondly, motor choice! is the 300D engine mentioned above going to deliver 'real-world' performance similar to what it does in it's original chassis? one on hand i would say yes, and another no. say if you do a minimal JY/BB (ZJ V8 coils and BP rear for about 2" lift) and the oil pan adequately clears i would argue you'd get close to the same MPG/perf numbers seen in the original car, however i'd argue it would 'feel' grossly underpowered compared to the 4.0L. even more so for going with +3" lift/+30" tires (even considering appropriate re-gear) it would likely feel wayy underpowered.

what about that isuzu NPR diesel commonly found in box vans? i don't know enough about them to say much. if the engine/associated hardware has a decent power/weight ratio and appropriate physical dimensions it could be a good choice.

and onto the 4BT: it's a 6BT less two cylinders, which unfortunately means even though it's slightly smaller end to end, it still weighs twice as much as the 4.0L removed, not to mention the top to bottom size difference...it's HUGE and HEAVY.

i would recommend reading the various links and articles found here: Novak Conversions - General Engine Conversion Options

weights and physical dimensions considered, the novak articles make a sound argument in favor of the LS1 GM V8 against pretty much anything else for mileage/efficiency
Oh yes. Totally agreed; the GM LS(x) series engines are amazing. Probably one of the best swaps one could perform on several vehicle types (240sx/Drifting, jeep, off-road, sand-rails, etc.etc) BUT, the main issue with those engines are the price tag. Not very affordable, unless you happen across one on craigslist or something.

Another argument against the LS(x) V8; with the Mercedes-Benz diesel, I can run BioDiesel, which anyone can effectively produce significantly cheaper than the regular petrol that the GM LS(x) v8 would use. One could also run WVO with an appropriate kit installed; WVO or waste-vegetable-oil is what restaurants just throw away, or pay someone to dispose of. They'd be more than happy to let you get it off their hands. BioDiesel, if properly produced, is much better for your engine and will actually increase its longevity and help it run better. Diesel fuel sold here in the USA is of poor quality when compared to European diesel fuel and BioDiesel.

Passing emissions is no big deal here in NC; all you must pass is a safety inspection for vehicles made 1995 or older. If the vehicle requires an emissions inspection in stock form in your given state then it may require additional work and may not be a good candidate for a diesel swap.

I really don't see any need to change the title or registration. Seems like an unneeded hassle. Here in NC, people regularly swap diesel engines into Suzuki Samurais without any difficulty; they do not alter the title or registration at all. It would be the same process with the jeep. As long as it doesn't require an emissions check (sniffer or where they hook into your OBD port/on-board computer) you will not have any issues passing. As for the DMV in TX, if you do not mention that it runs on diesel, they'll probably never know the difference (unless they are extremely anal and search the vehicle top to bottom). Here in NC, DMV officials/office personnel who handle the tag, title, and registration processing do not come in contact with the vehicle; the only people who come into contact with your vehicle are those who work at the inspection station/service station at which you get your vehicle inspected.

For early wranglers (4.2L powered) the OM617 is an upgrade in power and torque (but you must swap the Peugeot trans for an AX-15).

For any 4cyl powered Jeep, it is well superior to the stock 2.5.

For any 4.0 Powered Jeep the OM617 provides performance much like the original factory equipped 4.0 I-6. The Diesels horsepower output is a bit less (125hp) but the torque output is about the same (188ft/lb). Also, the Diesels torque curve is much better suited to trails; its peak torque comes in at low RPM, making it desirable for rock crawling and trail applications. Also, one can crank up the performance of the diesel by removing the rack limiter. If you add an intercooler, you will see a significant gain there as well. People have already breached the 300HP mark with these engines. Most only use a performance injector pump and elements paired with a few other external upgrades (no tearing into the engine is necessary) Toss on a larger turbo and you will also see a decent increase in output numbers.

People that have completed this swap report fuel consumption digits from the high teens to the low to mid 20's. Pair the fuel consumption to the low cost of BioDiesel and there is a clear and definite savings in fuel cost.

Most importantly, you can complete this swap for less the cost of a lower mileage LS(x) series engine if you do the work yourself. I know this because I've done the math.

Anyhow, hope you find my comments beneficial!

Cheers,
-Grimm
 
#19 ·
In an XJ or MJ, what would be needed for the swap? Is the OM617 one-wire hookup to the Jeep or would there be a plethora of wiring to move over and hack into?

What would be needed to make the factory Jeep cluster work in this vehicle, say a cluster for 97-01?

And finally, I keep hearing mention of the AX-15. Is this a direct bolt-to with the Benz diesel? If not, what needs changed? Could it be made to work with the XJ's automatic trans?
 
#20 ·
OK, i've been researching this a bit more as far as the OM617 into an XJ/MJ, here;s what i've got to contribute:

Mercedes OM617 diesel to Jeep Wrangler AX15 AX-15 NV3550 Adapter Kit

the adapter kit is to use the jeep flywheel/starter/AX15 trans on the MB OM617. the motor mounts in the link are for a TJ, but could possibly be adapted to work in an XJ, or would provide a good basis for figuring out XJ-specific mounts.

on a side note: the adapter plate would work to attach an AW4 to the OM617, but a new adapter to for the flex-plate would be need to be fabricated.

as far as the 97-01 dash/electronis etc, my personal plan is just to 'piggyback' the ECU/etc over the OM617, meaning when i turn the key on, everything will power up like usual, but to start and shut down i will use two extra switches on the dash.
 
#22 ·
that's it exactly. the speedo/odo works as usual since it's driven off the transfer, the water temp/oil pres/volt meter/fuel can all be operable with correct sending units/adapters, the only thing that won't function will be the tach, but a different one that does work could easily be installed in it's place.

the ECU will just think it's on but not running, but it will still move/function since the OM617 is almost entirely mechanical. the glow plugs can be wired in separately, from the separate starter switch perhaps?

if you're willing to do all the extra work, the harness probably could be reduced by half (see some threads on NAXJA jeepspeed section) like a racer, but why bother with a daily driver? the idea is to use as much of what is already there and functional.

i'm going to be looking for a donor 300D sometime between now and say april...
 
#23 ·
Have you considered the 2.8 VM Motori oil burner? I believe you can buy one new for relatively short dollars, and you can get a version designed for industrial applications which (perhaps?) doesn't require computer control? I casually looked into this a couple years ago, so this is just off the top of my head.
 
#25 ·
the one that came in the liberty CRD? i think even the industrial app one is common-rail (non-mechanical) and besides, the one in the liberty CRD got pretty bad reviews, not to mention finding one in a JY would be all but impossible.

my interest in the old benz om617 is that i can get the whole car for $1000-$2000 with relatively low miles. and for a conversion having an operational donor takes away alot of potential head scratching and scrounging for parts.
 
#24 ·
Bolts right up to the AX-15 eh? **** YEAH IM INTERESTED!!!

You want to sell this as a kit with the motor included?
 
#26 · (Edited)
As far as the wiring goes, the OM617 requires only a few wires in order to run properly. Its a cake walk. As are most any older mechanical diesel engines.

Only issue in swapping when it comes to gauges is the tach; you will need to use the tach from the donor car.
OR
If you wish to have a different tachometer, you can construct one by building a simple circuit; a "rotation counter". If you put a mark on the crank pulley, you can build a circuit that counts each time the mark passes a sensor, translating into rpm readings. If you use a micro-controller, you can include features such as digital and fully programmable cruise control, and also a digital hand throttle (using cheap servos). You can also program the engine to idle higher or lower according to ambient air temperature.

Nathan Koch (pronounced "Coke") of Koch Enterprises makes the adapter kit. I have personally spoken with Mr. Koch and have been granted his permission to sell and offer his conversions through my shop. I am not the manufacturer of the adapter, I own a shop in NC and will possibly build and sell a complete vehicle turn-key. I perform these conversions on an appointment basis. Koch Enterprises does not offer engine mounts for the XJ Cherokee at this time, but if R&D continues, I will offer engine mounts through my own company. Mr Koch is currently developing a kit to bolt the OM617 to the AX-5 5-speed used in most 4 cylinder wranglers. According to Koch Enterprises, they aren't developing an adapter for any automatic transmission at this time and the most current project underway is an adapter for the Toyota 4-Runner.

The OM617 uses no ECU. The absence of the Jeep ECU will have no effect on the diesel engine running; its totally mechanical. The ECU may be needed to run other parts/accessories of the Jeep.

The factory engine harness from the Jeep will remain largely unused. The ignition wires will be used, along with all wires relating to any electrical accessories/utilities unrelated to the engine that you wish to keep in working order.

If you wish to keep your AC, you'll have to marry the Jeeps AC controls to the new AC pump/system. Your heat controls should still function properly if the wiring is left untouched, as long as the heater core is attached to the OM617 properly.

As for the Motari 2.8 CRD Diesel; I do not know very much about this little engine, but I have seen several of them involved in engine fires. I'm not saying that they are bad engines or prone to spontaneously bursting into flame, but just stating the fact that Ive seen several of them in such condition, which may be nothing more than mere coincidence. One thing is certain; there are not many of these engines and they are a bit more expensive than the Mercedes diesel. They also require an ECU, therefore installation would be considerably harder and more time consuming due to the wiring. To conclude; the 2.8 Motari Diesel is still quite new and I have yet to find any substantial evidence backing up its longevity, durability, and reliability in the long run, as many vehicles powered by this engine still have yet to reach the digits considered "high mileage" here in the US. Compared to the 2.8 Motari, the Mercedes-Benz OM617 has, over several decades, rightly earned its reputation for being incredibly long-living and durable.

Unfortunately for this thread, and fortunately for myself, I have located a beautiful Wrangler for sale and may go that route as opposed to purchasing and building a Cherokee of this sort, but I will continue monitoring this thread and answering questions about this engine and conversion.

-Grimm
 
#29 ·
Unfortunately for this thread, and fortunately for myself, I have located a beautiful Wrangler for sale and may go that route as opposed to purchasing and building a Cherokee of this sort
-Grimm
And do what? Put on 2 inches of lift, 31" tires and some KC hi-lights?

Come on man be original, here's your chance :cheers2:
 
#34 ·
Ok I'm going to have to give this some serious thought.

BTW, I love the 2.8 CRD. It's got several issues, most of which brought on by stupid emissions requirements, but a common rail is not a good drop in due to it's complexities and expense.

I wonder if the Mercedes radiator can be made to fit into the XJ/MJ header panel.
 
#39 ·
I did a little checking today and my 83 Mercedes 300SD with the 617 turbo diesel engine has a GVW of 4775 LB and my 90 Jeep has a GVW 4900 LB and with the much larger tire diameter on the Jeep I can see where you would be better off tweaking the engine a bit. I have good acceleration in my Mercedes but there isn't much in the way of extra power. You don't feel turbo in the MB until around 2300 rpm so anything you could do to get that to happen sooner would be a big help, like a more open exhaust system so less back pressure.
 
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