Comanche Engine Question

[Mack4194]

Hello all, I've got a couple of questions I thought I might ask. Anybody have a diesel engine in there Comanche? Anybody have one they don't want anymore?

 

I know that there were two little diesel engines 2.1 and 2.5. Does anybody know of another larger diesel that would go in without to much difficulty?

 

I'm trying to increase my gas millage and I'm tired of worrying about going through water.

 

 

 

Thanks for reading and please............ be gentle with me :)

[Dave Stark]

Another option may be the Cummins B3.3T, it has similar torque & weight as the 4.0, but is lacking a bit in the horse power department, but supposedly can be tuned a bit with an inter-cooler. Be aware if this is the direction you want to go, it is an industrial engine & may not pass inspection in your area...

 

There's also a member on here that has installed a Cummins 4BT, but i think he had to have a 6" lift to fit it in the engine bay.

 

Others have spoken of using a Mercedes diesel, but i haven't personally seen one.

 

~Dave

[Mack4194]

Dave, thanks for the reply. I would love to know who this member is so I could speak to him. My comanche is lifted 8 inches ;) I'll try to research on the mercedes engine swap.

[Pete M]

swap in a diesel cause it's more powerful.

 

swap in a diesel because it's cool.

 

don't swap in a diesel because you think it'll save you money. you'll never recoup the cost of the swap. :thumbsup:

[Geonovast]

What was the 2.5 diesel in? :hmm:

[Mack4194]

2.5 diesel was in Europe, although if you look around you can find one in the states every now and then. It's just to weak to be in a comanche IMHO

[Mack4194]

I'll really never recoup the cost of the swap??? :( Well can I at least tell my wife that we will??? lol

 

 

That's kind of what I was trying to see. How dificult is it to do the swap if I can find a cheap good engine on CL or at Junk Yard or something.

[Pete M]

what size tires and what gears are you running?

[Mack4194]

I've got 35 inch tires with 4.56 gears.

[Pete M]

oh good. I was afraid you were still pushing stock gears around. :D 4.0 or 2.5?

 

the old MJ diesels were anemic piles. and parts are super expensive, if you can find them. We had a member down south that put a merc 5-cyl in his MJ. got it running and everything only to lose it in a hurricane. haven't heard from him in a while but I'd imagine you can find some info in the archives. be sure to check the tech and the projects forums

 

be aware that diesels are big hulking bricks that weigh a ton and really don't fit well in the engine bay. you'll need a new trans, new mounts, new fuel delivery system, new exhaust, new radiator, new trans mount, etc. not even sure what sort of wiring you'll need to do to get the guages working. just about everything in your truck will need to be replaced or modded to make it work. a chevy v8 might actually be cheaper.

 

 

also, out of curiosity, what the heck sort of fuel economy do you really think you'll get from an 8" lifted MJ on 35s, even with a diesel?

[Mack4194]

I was hoping to get high 20's maybe even low thirties. My truck get about the same now as it used to with the stock gears (3.07) My truck is the 4.0 Metric Ton Model. I love the heck out of it :)

 

I just find the diesel apealing

[Pete M]

sorry to burst your bubble, but there's just no way that'll happen. our bone-stock CRD libby can squeak out those numbers, and your Jeep has a LOT more wind/tire resistance. as I said before, do it 'cause it's cool, :thumbsup: don't do it to try and save money. :no: the engine block alone can set you back a grand. :ack:

 

did you swap speedo gears to account for all the tire/gear changes?

[Mack4194]

lol no I didn't. 70 is 55 ;) I've got them figured out now, I've been lifted for quite a while now.

 

You're sure I won't get increased milliage?

 

 

My milliage didn't really change at all when I lifted my truck, I maybe lost 1 or 2 mpg tops

[Pete M]

all I'm saying is that any increase you might see won't be big enough to offset the investment you'll be sinking into the diesel swap.

 

how many miles do you drive it a year?

[Mack4194]

yeah I can see that, but I'm a scavanger. I usually find good deals and I only by new when I have too.

 

I drive about 5-7K a year I suppose

[Pete M]

what mpgs are you seeing now? also, how are you calculating that?

[kro10000]

The 5 cyl mercedes diesel Pete is talking about is the Mercedes OM617, if you google that you will get some more info. My buddy and I got a deal on one for his XJ for $200 after we pulled it from a 1985 300D, this one is going in place of the 4.0 in his 88 XJ. After tuning it up a whole lot you might pull similar power level to a renix 4.0, but we should pull some pretty darn good fuel numbers. Also the plan is to run it on WVO so we should be able to cut out almost all fuel costs. I'm using his swap as a guinea pig, so hopefully whenever I get around to a similar swap in the MJ, it should go relatively seamlessly.

 

The packaging of the OM617 is one of the best parts, width-wise its a relatively perfect, and since its an I5 in place of an I6 you won't have issues with length. The oil pan usually will interfere with a stock height MJ, but shouldn't have an issue with some lift.

 

Pics of the OM617 we pulled, sorry they are from my phone, so a little blurry

 

Good Luck!

[HOrnbrod]

Check out this link, search around, lots of good info from guys that have actually done the Benz OM617 transplant into the XJ/MJ family. I'd love to try it. :cheers:

 

http://www.dieselbombers.com/diesel-engine-conversions/

[carnuck]

If you do the Mercedes diesel, you'll want to find a Mog oilpan for clearance.

 

I'm vying for a Toyota 2LT for mine because they use a version of the AX-15 and that will make it an easier swap.

[Mack4194]

Thanks for all the info guys. It looks like this is a highly desired conversion, but it looks like it takes a fair amount of doing.

 

I think it is the project I will use to christen my shop when I get it built in my back yard :) I've already got a lift I bought from my father in law when he closed his automotive repair shop. Now I just need a building to put it in lol :)

[johnj92131]

I saw a Toyota Tacoma last weekend with a VW 1.9 TDI. He has goosed up the power with a chip, bigger turbo and larger intercooler. Used an Acme adapter to mate the VW to the Toyota 5 spd.

 

 

 

Said he gets 30 mpg and I believe it. His engine should put out at least 140 hp and 275 ft/lbs of torque.

 

I own a 96 VW Passat TDI and chipped my engine just this weekend. Here is an example of the power increase:

 

http://malonetuning.com/?page_id=62

 

Go down the page to "Stage 3". Adds 40 hp and 75 lbs/ft or torque. Does this (in part) by taking stock boost from 12 lbs to 17.5 lbs. Also changes the fuel maps.

 

As a bonus, it takes close to 200 lbs out of the truck.

 

Understand the OM617 Mercedes is bullet proof. But the power output is low, even in the turbo version. Understand the injection pump is the power bottleneck..

 

Might want to look for a 5 cylinder engine from a Sprinter. It would be a CDI engine and can be chipped for a few hundred dollars.. Much more modern.