Diesel swap: help needed

[dforester]

Well ladies and gentlemen, I'm taking the plunge. I believe I will be picking up one of mistermg's blown engine VXs in the next two weeks, and since it has a dead engine I might as well swap a diesel in there.

Yes, I've read all of the threads I can find on this site on the subject, but I'm still going to need a lot of technical help from you all to get this done. I'm going to have a shop here in town help me out with this (there's no way I could do this by myself), but the more planning I have done ahead of time, the easier and cheaper this will be in the long run.

I also realize that there are some people that object to a diesel swap as it is not holding true to the ideals the Isuzu designers had in mind when they created the VX. Ummm, maybe. But clearly the 3.5l engine had some design issues, otherwise the VX I'm buying would have a working engine. So, since I want an engine that will last for as long as the rest of the vehicle, and since there's a biodiesel station (B20) around the corner from my house, and since I want to get significantly better than 15 mpg, I'm going diesel.

What seems to me to be the best option is an Isuzu 4JB1 engine with turbo and intercooler. It looks like this engine was in the overseas Rodeo and Amigo (or MU), so it should be a close fit for the Viacross. The 4JB1 has a beter reputation than the more current 3.1 L diesel (Bighorn, etc), it uses less fuel and it is still standard equipment in Bobcats, skid steers, etc so I'm hoping I could get parts without too much trouble. I'd like have an automatic transmission that uses the TOD, but I'm not sure the stock transmission will handle the torque from the diesel engine.

This is where all of you come in. I need advice, thoughts & comments on this engine choice, what I should use for the transmission, where I can find a reasonably priced engine, transmission, etc. Has anyone on this forum successfully done a diesel swap? Am I a complete idiot for taking this project on?

This is the type engine I was thinking about using:

http://cgi.ebay.com/ebaymotors/JDM-U...spagenameZWDVW

I can't tell you how glad I am that this VX community exists. One of the reasons I'm taking this on is because you all are such an amazing base of knowledge and helpfulness.

Thanks in advance,

Dave
Santa Fe, NM

[Triathlete]

I can't tell you how glad I am that this VW community exists. Thanks in advance,

Dave
Santa Fe, NM

[etlsport]

Dave,

I would start by sending PMs to joe black and kpaske, they are the two i remember being most serious about a diesel swap and iirc kpaske actually started collecting parts for the swap before deciding to sell his vx

[tom4bren]

"I'd like have an automatic transmission that uses the TOD, but I'm not sure the stock transmission will handle the torque from the diesel engine."

The TOD is probably where we lose so much of our efficiency (gas mileage). I like the TOD so would probably keep it too but if your main goal is improved efficiency, you may want to consider swapping to an operator selectable transfer case.

If you're going to keep the TOD, I'd keep the tranny too. As long as you won't be pushing the beastie to the limit, I don't think the torque will be an issue (IMHO).

I think I'd be worried more about the computer. How in the 1134 are you going to handle all of the sensor outputs??? I'll be the first to commend you for going green but you're biting off more than most of us would be willing.

[JHarris1385]

This is going to be an interesting thread. My commute to work just doubled (and a little more) from about 10-16 minutes to around 35-40. So iv begun to think about making mine more economical or maybe just not selling my other auto and driving it on a daily basis, but again I cant stand not driving the VX. So maybe I will deraise (lower it to stock) and see if there is much of an increase in mpg. All in tall if this works out and is not >$5000 I could be game. Tysamigo does have plans for going full electric in 2 years or so.

[ZEUS]

I am a believer of one-stop shopping when it comes to swaps. I know you would rather not use the bighorn but lookie here: http://cgi.ebay.com/ebaymotors/91-96...spagenameZWDVW

Of course, it would be even better to have the entire vehicle with computers, senders, and preassembly. Taking a carcass AND a donor vehicle to someone is the most efficient way to get the job done, IMO. I would suggest talking to a shop near you and asking them if they would even take on such a project, then question them on specifics to see what you are up against.

[tom4bren]

JHarris - Welcome to my commute nightmare (45 miles & 1-3 hours each way, prolly why I've become such a procrastinator).

"So maybe I will deraise (lower it to stock) and see if there is much of an increase in mpg."

Lowering your vehicle won't help with gas mileage unless you put whimpy rubber on to match. Lifts are almost always accompanied by taller & more agressive tires. That's what kills your mileage. The taller tires effectively lowers your gear ratio & the more agressive tread increases the rolling friction. The only thing lowering the vehicle will do is MAYBE increase your aerodynamics & MAYBE decrease the friction at the CV joints (neither will be measurable differences). IMHO - it would be a waste of time.

[Chopper]

The mix and match route is the toughest. Dump the tranny, and TOD too. The easy route , is to go with a donor vehicle, and transplant the entire driveline.

[uncle_asa]

My dream is to get JDM Isuzu's Mu and Vehicross and put Vehicross body on top of Mu driveline and frame (actually the frame is the same, but from the terms of registration of the vehicle it is easier in Russia). I believe you will need almost complete donor for this project: computer, wirings, engine, transmission... You know, after that all you hardly will care about MPG

[Joe_Black]

I'd stay away from the 4JB1 as that's an 80's era diesel from the 1st-gen Trooper and even with the intercooled turbo it's not very well suited for the VX. The 4JG2 is what you want to look for, and you can find them typically complete with auto or manual trannys. I haven't yet seen one with TOD, but the unit from the 3.5DI Axioms and Rodeos should be up to task since they came with the beefier Aisin auto and 2WD selectable TOD unit. From what I've seen in the JDM service manuals it should mate right up, but you'll likely need to get a custom controller as the tranny's shift points are set up for gas. Personally I'd go manual to get the most performance, but you'd still likely need a custom adapter to retain TOD. At least the VX has a place to hang the clutch pedal! Advance Adapters may be a good place to query if you intend to keep TOD. Steer cleer of the 4JX1 as it's a common-rail mill and as such needs an ECU to run, whereas the 4JG2 doesn't care if you've got a battery anywhere near it once started.

Definitely stay away from any engine importer where they show photos of the engines sitting on concrete. If it's not on an engine carrier or pallet you could end up replacing not only the sump and pan but any number of ancillary components that were crushed or ripped off in shipping and handling.

The last time I went on a serious 4JG2 shopping expedition there was only one decent place in Japan and several breakers in the UK with fair pricing and good selection. That was two years ago but I ended up spending the funds putting our daughter into private school instead and now daily drive a Mk5 Jetta TDI while my wife uses the VX for her daily 20 mile work/school circuit. I still plan the convert as I believe a diesel VX would pretty much dominate ANY gasser VX. Not to mention I can't make gasoline but will soon be cranking out quite a bit of B100.

Good luck, keep us informed and be sure to do plenty of research before making the drivetrain purchase. There's absolutely no substitute for a well thought-out plan when it comes to vehicle builds as the details make all the difference when things start lining up, and that's definitely the better alternative to sitting in a garage full of worthless parts with an empty wallet and broken dreams.

[eternal21]

Hmmmmmmmmmm.....

http://www.ebay.com/itm/ISUZU-TROOPE...840bf7&vxp=mtr

[Triathlete]

Hmmmmmmmmmm.....

http://www.ebay.com/itm/ISUZU-TROOPE...840bf7&vxp=mtr

Thats a pretty good deal considering it has the tranny, tcase, wire harness, computer and front drive shaft.

[vt_maverick]

Hard to say it's a good deal if they don't list the mileage...

[eternal21]

Hard to say it's a good deal if they don't list the mileage...

It's a JDM engine, so I'm making an educated guess that the mileage is ~50k or less. I'm more surprised to see the MT than I am the engine, TBHWY.

[Triathlete]

True
Should have said potentially a good deal