Isuzu 3.9l Turbo Diesel

[KPhillips]

Any you guys have any experience with this engine? In my endeavor and research to find a good diesel conversion for my Jeep Scrambler I have found that this may be a good swap consideration from one of fellow our Jeep tech guys,,,



Heres a snip of out of an BBS conversation he had with a guy that knew about the Isuzu TD



"snip"

"I have found what I believe to be the ULTIMATE diesel motor for swapping

into formerly gas vehicles. It's a 3. 9l Isuzu turbo diesel that makes

120hp. It's used in those "cab-over" 3(?) ton trucks which I beleive are

sold both as Isuzus (don't know the model number) and as GM 3500s. I

recently saw one in a Land Cruiser and it's a VERY clean conversion. A

factory Isuzu bellhousing is available that will mate to a Chev SM420. All

you'd have to do is get an SM420 (7:1 first gear--should crawl respectably

and either an adapter that would go between your transfer case (Dana 20,

is it? I'm not real good with Jeep stuff) and the SM420 OR get an SM420 and

a Chev-application transfer case that has the driveshaft outputs in the

right spot for your Jeep". "Snip"



So it looks like it could be a decent candidate for a swap,,,anyone got any additional info, pictures, prices, locations where to get these, etc.



Just trying to get some opinions and experience from anyone who may know anything about them,,,



thanks,



kerryp



.

 

[bigkid59]

Hello Kerry!



I just looked this engine up in the Cummins and Competitive Automotive Engine Specifications book that I have.



According to this information this engine is 236 cubic inches with the same 4. 02" bore of the B series Cummins but with a stroke of 4. 64" where the B series has a 4. 72" stroke.



These were known as the QD-100 (4BD1) or the QD-100T (4BD1T) depending on whether they were turbocharged or not. I have seen quite a few of the turbo models but have never seen a nonturbo in person although I have seen a picture of one in a Chevrolet 1/2 ton pickup.



The Isuzu trucks that have this engine are NPR series and are 1 ton rated. The GM series made by Isuzu are the W series.



The info I have in this Cummins booklet shows a weight of 743 pounds for the turbo engine compared to 705 pounds for the Cummins 4B with turbo. Not enough difference to really matter.



The 4BD1T makes its rated horsepower at 3000 RPM and its rated torque at 1900 RPM compared to 2500 RPM and 1700 RPM for the Cummins. This would call for some research into what would be a proper gear ratio, since it would be higher numerically than with a Cummins.



There are also 6 cylinder versions of this engine that weigh 1056 pounds.



I have known a few people who have owned these NPR Isuzus and they have pretty much gotten good service from them. The only problem I ever heard of was a broken crankshaft in one being used as a wrecker. The owner did not blame it on the truck but on the several different drivers that had run the truck into the ground. He installed a rebuilt engine and kept going.



Sounds like a good second choice to the Cummins. Good Luck!

 

[KPhillips]

Great info bigkid59, thanks alot, sounds fairly comparable to the Cummings... any idea what the aftermarket is like for these and if replacement parts are priced in the same range as a Cummings?



Those factors would also be a consideration in a swap... I'm not sure if I would do too much to any diesel I transplanted into the Jeep (performance wise) because the Jeep isn't in need of raw horsepower for what its used for,,,,



does your book give the actual HP and torque ratings for the Isuzu? I think the Cummings was like 105hp and ,,,,I can't remember the torque, and I thought I read somewhere that the Isuzu was rated at like 120 or so HP...



thanks again. .



kerryp

 

[cjohnson1]

Kerry, You may want to think about the Isuzu powerplant. The biggest drawback is the size and weight for the output you get. I have every book you could ever want to see about this motor. The 4 cyl is just as big as the 6 cyl. It's very tall. Ever bit as tall as the six.

When I get a chance tomorrow I'll pull them out and look up anything you need to know.

I almost bought a 6BG1T for my motorhome, but had to give it up as I could not find anyone who could tell me how to BOMB it with any certainty.

There is one guy who used to teach the Factory mechanics at Isuzu and is reported to live in the Irving Texas area. I can't find him to save my life.



So, if you want, get you question ready and shoot me a PM and we can put our heads together on the Isuzu diesels.



BTY, We're building a Cummins for the MH.



Curtis J

 

[E7mack96]

Isuzu

I have personally witnessed three of these engines die a horrible premature death. All were in the npr /w4 box trucks. one blew the engine within 6 months, warranyty covered, no explaination as to why. One cracked the block due to overheat when hose blew. (Not driven far after incident, just to safe side of road) One blew to overheat after driver drove all day with low water.



Personally, I don't think they are in same league as the Cummins

 

[KPhillips]

thanks cj and E7, I think that just from what I have learned from these three posts I will probably stick with a 4bt Cummings for my swap,,,,when and if I can find one cheap enough,



my biggest concerns on the Isuszu were dependability, parts availability, and performance enhancements all of which are covered on the Cummings, They don't appear to be well covered on the Isuzu and I don't have the warm and fuzzy feeling for it... thanks, for the info. .



kerryp

 

[cjohnson1]

Kerry, I did find a guy in Grandbury South of Fort Worth who can fix you up with any Cummins engines and the pieces for a repower. If you interested! He's building my 5. 9 l for my MH as we speak.

His name is John Edwards and the phone # is 817-279-0400. He's one of the most reasonable price places I've found so far. He knows his stuff and is a great guy to deal with. We've became friends very quickly.

Curtis J

 

[KPhillips]

thanks cj,



I may give him a call, I don't even have funds yet... you have any idea what he might ask for a used 4bt with transmission? Just curious... I'm really getting the itch to do this swap... . anyone need AMC 360 engines and transmissions for their Jeeps, I have two one with 5 speed, and one with 727 AT...



kerryp

 

[cjohnson1]

Sorry, No idea on on his prices on the 4BT.

I believe he has one or two in the shop right now that are ready to go. Give him a call Monday and check him out. Tell him I sent you and he'll take time to talk to you. Everything you want to know!

Put your AMC motors up for sale on either E-Bay or post them on the Pirate Board and the 4X4 Wire Board "For Sale" sections. They are both free and have a large Jeep readership.

I can shoot you some links later if you'd like .

Trying to get ready for Church so gotta run for now.



Curtis J

 

[KPhillips]

thanks,



I'm actually a regular on the POR and Off-road BBS, as well as Rockcrawler, cj-8.com, dirtroad.com, etc. . I'm an information junkie, the more I have the better I feel ,



I was just joking with the 360 post, I knew noone here would likely be interested in an AMC 360 ,



thanks, when (if) I get some funds together I will give him a call



kerryp

 

[Todd G]

I've owned a dozen or so Isuzu NPR's and FSR's over the years. The 3. 9's are a very reliable motor and last a long time with decent maintainance. The only real problems I've encountered are with burned pistons 3 times. This occurs when a driver of mine would go for about an hour with the throttle pinned going up mountain grades. I wouldn't do that to my Cummins! Parts are very reasonable and there are thousands of wrecked trucks out there to salvage. The last one I bought had the 175HP 4-cyl and it was very quick. 4 valve head I believe.



If you want real reliability, use the 6-cyl model from a FSR. I put 350,000 on one and didn't do a thing to the motor. Most of the time these motors are at idle for an hour at a time or at full throttle. The last I heard, that truck had 500,00 on it with no problems. It was a heavy beast for a 5. 9L though.

 

[DT]

go with isuzu

Don't get me wrong, I like Cummins, but if you can get an isuzu, go for it. I have seen those things run for 500,000 miles in service trucks and about 10,000 hours in link- belt escavators. In fact, I just got done putting a 6BD1H (5. 8 l, direct injected diesel) Isuzu into my truck, with an allison at542 behind it, and an NP208 transfer case behin that. Just got a little more custom intercooler work to do and it will be ready to go.

Here's a link to my website with some pics, sorry, I haven't taken any pictures of it in the truck, yet, I'll try to take some pretty soon.

http://www.picturetrail.com/turbokid



btw: the 6bd1 and the 4bd1 are dry-linered engines, unlike the cummins.

 

[cjohnson1]

DT, Your the first guy I've heard from who has done this swap. I had a complete 6BG1T and Allison transmission found for my motorhome but couldn't get it to go over 60 mph in the empty doner truck. Ran like stink up to 60 mph but just wouldn't pull after that. And no it wasn't a govenor problem, cause the engine ran out of power on the slightest hill. I was all ready to pull the drivetrain until I drove it. Oh Well. I have yet to find anyone who could tell me how to boost the output. I'm a big Isuzu off road fan and would have loved to power my Motorhome with an Isuzu as well.

I gave up on it after spending a small fortune on Isuzu diesel manuals. I just don't have the diesel experience to be able to hot rod one without a lot of help. Soooooo! I have a guy close to me building me a 300 HP Cummins.

Hope to have the bus repowered before Summer gets here.

Nice job DT, Looking forward to studying your pictures closer later this afternoon.

Gotta get off the salt mine.

CJ

 

[KPhillips]

Thanks for the info DT, I will check into it further before I make my final decision to go with the Cummings, please let us know how yours runs in your truck>



I'm curious to see if you have the same issue as CJ... . I have to be careful if I put an Isuzu in the Jeep because I don't want my Dodge CTD to shun the Jeep and cause a whole lot of family issues, you know :-laf



kerryp

 

[DT]

cjohnson- I have actually heard of a few other people who have put a 6BD1 in a Chevy- they haven't had any problems.

I don't know what the problem was with that 6BG1T. (which is a newer engine. ) I took mine for a spin around the block without the intake completed and I got it up to 65 mph- that's even with 4. 10's and no O. D. I plan to swap in a higher ratio soon.

I have already turned up the pump (inline). I put the turbo on this engine, it was formally NA. Can't wait to see how it runs with the intake completed.



kphillips- let me know what you decide and how it fits... thinking about putting a little diesel in my jeep.



BTW- This engine had been sitting for 9 years without running. When I acquired it, I bled the fuel lines, cranked it over about twice, and it fired right up!

 

[KPhillips]

DT,



just out of curiousity (if you don't mind revealing) how much you paid for the engine you put in yours, how many milesdid it have on it and how much did it cost you to turbo it??

 

[DT]

It cost me $1500 for the engine and the truck it came in. The allison cost me $95 from a very weird old man. (I'm not kidding. ) The engine has about 30,000 miles on it. runs great, no blowby, took off the valve cover and everything looks great, valve clearance is still exactly what it's supposed to be. (. 016) The transmission by the way only had 44,000 on it and was working great behind a 5. 9 B in motorhome before the crazy old man decided he needed an MT643 allison.

It actually didn't cost anything to tuirbo the engine, I did some reasearch and I was able to use a turbo I already had. I welded the manifold and everything, so that didn't cost. I am also making a custom intercooler, which doubles as a grille.

 

[cjohnson1]

Originally posted by DT

It cost me $1500 for the engine and the truck it came in. The allison cost me $95 from a very weird old man. (I'm not kidding. ) The engine has about 30,000 miles on it. runs great, no blowby, took off the valve cover and everything looks great, valve clearance is still exactly what it's supposed to be. (. 016) The transmission by the way only had 44,000 on it and was working great behind a 5. 9 B in motorhome before the crazy old man decided he needed an MT643 allison.

It actually didn't cost anything to tuirbo the engine, I did some reasearch and I was able to use a turbo I already had. I welded the manifold and everything, so that didn't cost. I am also making a custom intercooler, which doubles as a grille.

NOW That's bizarre



~:--)

I got my Allison AT542 from a guy who did a swap for a crazy ol man who also wanted a MT643. Don't know why they would want a manual shift transmission, but that's the same story I got here in Texas on my transmission. Ony it has 38,000 miles on it. It too was in a pusher motorhome.

Hows that AT 542 working for you? I'm wondering if it will give me the performance I want without and overdrive box behind it. Anthing will beat the C-6 that's in it now. (can you say GUTLESS?)

I 'm expecting the Cummins to be ready in about 4 to 5 weeks.

I picked up a new Isuzu Intercooler last week. I'll post a picture of it later tonight after I get through with some Honey-Do's. ALl indications are it will fit perfectly.



Wup! Gotta run,

CJ

 

[DT]

:--)

That is weird...





I haven't driven very far with the allison yet, but it has done me good so far. I'd say that it would work.

I saw an AT545(newer version of 542) behind a cat diesel- about 8 liters(I think 3126 or 3116) turbocharged and aftercooled. It was in a custom 6500 Chevy crew cab(had a pickup bed on it. ) It was from New York and was a trailer puller for a guy at the Easter Jeep Safari in Moab, UT. It seemed to hold up fine in that application, so I'd say that a 542 would work behind a B to as probably as much horsepower and torque as you want to bomb it to.

That's just my opinion, though.



That intercooler sounds good...

 

[DT]

Just thought I'd post real quick for those of you who have already looked at those pics... I just posted some pics of the engine in the truck at http://www.picturetrail.com/turbokid



tell me what you think... still got a little bit to do...