Building a diesel powered RHD TJ Wrangler (Picture Heavy)

[RustyAutoholicGuy]

Soooo...got all excited about this swap and started doing a little digging on line for engine specs, availability & etc. In the process, the wife called. During the conversation, I mentioned the swap you're doing. SHE got all excited. Crap. Now I have to do some math.

A couple of questions for you...

How noisy is that Kubota? The old school diesel rattle makes her nuts.

What, exactly, am I looking for when I search for a Kubota V2403? It appears the newer ones are electronic / common rail. Is that correct?

The Kubota swappers web site is pretty sparse, do you have additional resources to investigate? I'd be sticking with my manual transmission, so your point about engine position is a good one.

Still going through all of your videos...cool stuff!

Okay so a ton of information to go over here. In terms of noise I was surprised by how quiet the engine is. What's nice about these Kubota Engines is that they are 2000~2012 diesel injection technology. This really means one thing! The injection is MUCH more refined than the older diesels like a 4BT or an OM617. Here is a video of my V2403 engine test un-edited.

Also consider this engine is only like 414lbs vs the 4BT's massive 775lbs and the OM617 585lbs as well. That reduced massive is really going to help with noise and vibration from the diesel engine.

Truthfully I think this is about the same noise level as my Kobalt quiet series air compressor. Also it's SMOOTH! It doesn't look like it in that video, but that was the first time I got the V2403 to ever run, so it was getting the air bubbles and crap out of the injectors. If you watch the engine gets smoother the longer it runs. I wasn't running coolant or anything through it so I didn't want to run it that long!

I thought I had my GoPro running but in the only other run I did I REVed the V2403 a couple of times and it was smooth and quiet considering there is no exhaust or muffler on the engine at all! I honestly believe that once the engine has an exhaust with a diesel catalytic converter and muffler it's going to be VERY quiet.

Also I'm going with Brown Dog Offroad's super flexible rubber motor mounts for an XJ, which I know an XJ motor mounts work in my setup, which are suppose to really help with suppressing engine vibrations.

So the answer to your first question, because of the newer diesel technology, exhaust, cat, muffler, and super flexible rubber motor mounts there should be very minimal noise and vibration.

Okay onto the second question. If I were you I would be looking for a Kubota V2203 not the V2403. The V2203 are the most common engines, most of them came out of refer units when California changes it's emissions laws and I see them for sale all the time. Here is a generic eBay search:

Kubota V2203 eBay Search

There are two types of V2203 IDI and DI which stand for Indirect Injection and Direct Injection. The DI motor's will have about 15% more horsepower and torque compared to the IDI motors. Other than that they are the same. I wouldn't spend more than $1300 on an IDI and more than like $2000ish on a DI, but that is just me. I've seen them on craigslist and facebook for sale as well.

I honestly can't tell you about your manual transmission. I would imagine that 2" forward would not be terrible and at that distance it would be easy enough to just build another set of frame mounts on your TJ frame out of some metal. Running an AX-15 or NV3550 should be great, though I worry about the AX-5, I just don't think it can take the torque. Another thought it looking for another transmission you might want to run, a stronger one that is slightly longer because you can offset the length with where you want to mount the engine.

On the additional resources not really. I actually original got into the Kubota with a V1903 that I was going to be putting into my 1947 CJ-2A, I had gone with a completely different adapter and everything for that setup, but project is much more crazy that this one and now I'm getting a custom frame cut so I can weld it together that I decided to tackle my TJ Wrangler first.

I've being doing the research around this Kubota engine since March 2016 and I'm just now getting around to doing something with all of that research.

Let me know if you have any more questions!!! I'll do my best to answer!!!

Thanks
Grant

 

[StG58]

Grant, you're a prince! Thanks for the additional info.

Now, do I really weant to show the wife the video of your engine running? It sounds good to me, though I don't have any idea what she will think.

On the transmission...an AX-15 is definitely the way to go in my opinion as well. You can break the AX-5 pretty easily behind the 2.5, so I can't imagine what 300 ft/lbs of torque would do to it. lol probably grenade in the driveway.

Thanks again for the info!

 

[Chris]

@StG58... DO IT!

25mpg, diesel, and an awesome engine swap... If I hadn't just dropped 5k on a supercharger I might have to seriously consider this.

 

[RustyAutoholicGuy]

Grant, you're a prince! Thanks for the additional info.

Now, do I really weant to show the wife the video of your engine running? It sounds good to me, though I don't have any idea what she will think.

On the transmission...an AX-15 is definitely the way to go in my opinion as well. You can break the AX-5 pretty easily behind the 2.5, so I can't imagine what 300 ft/lbs of torque would do to it. lol probably grenade in the driveway.

Thanks again for the info!

Always!!! My entire goal of this project is to show people what it takes to convert their TJ Wrangler's to a diesel.

Another thing, most of these engines are not factory turbos, though my V2403 was!!! You can turbo the non-turbo engines without issues, you will just need to adjust the fueling which from the factory was detuned to 30% of it's capacity.

I don't remember the procedure for tuning the engines, KubutaSwapper's has his own way of doing it, and that is how I'm going to tune mine when the time comes.

As for the turbo I'm using a Borg Warner K03 turbo from a TDI. I found one brand new on eBay for like $400 bucks and it should be between 25 ~ 28 psi of boost. If you are going to run OVER 14psi of boost you MUST intercool cool the charged air going into the diesel engine or else you are going to melt the Kubota engine.

Other turbos work as well, and you can get I think a GT15 turbo that does like 14 psi boost and run it with no intercooler, but I want to get as much HP and torque as possible.

I'm sure there are other things I'm forgetting as well!!!! If you have any other questions just ask!!!

-Grant

 

[RustyAutoholicGuy]

@StG58... DO IT!

25mpg, diesel, and an awesome engine swap... If I hadn't just dropped 5k on a supercharger I might have to seriously consider this.

Sell the supercharger and you can EASILY afford the Kubota engine and adapter

Honestly I'm so excited about the potential of a 30+ mpg TJ Wrangler. I still can't believe the MPG of my Liberty and I've owned it for 4 years and put 120K on the Liberty!!!

-Grant

 

[StG58]

@StG58... DO IT!

25mpg, diesel, and an awesome engine swap... If I hadn't just dropped 5k on a supercharger I might have to seriously consider this.

Always!!! My entire goal of this project is to show people what it takes to convert their TJ Wrangler's to a diesel.

Another thing, most of these engines are not factory turbos, though my V2403 was!!! You can turbo the non-turbo engines without issues, you will just need to adjust the fueling which from the factory was detuned to 30% of it's capacity.

I don't remember the procedure for tuning the engines, KubutaSwapper's has his own way of doing it, and that is how I'm going to tune mine when the time comes.

As for the turbo I'm using a Borg Warner K03 turbo from a TDI. I found one brand new on eBay for like $400 bucks and it should be between 25 ~ 28 psi of boost. If you are going to run OVER 14psi of boost you MUST intercool cool the charged air going into the diesel engine or else you are going to melt the Kubota engine.

Other turbos work as well, and you can get I think a GT15 turbo that does like 14 psi boost and run it with no intercooler, but I want to get as much HP and torque as possible.

I'm sure there are other things I'm forgetting as well!!!! If you have any other questions just ask!!!

-Grant

Chris, you're killing me here...lol. It's in the wild-ass idea stage.

Grant, let me think on this a bit. I'm sure I'll have more questions once it rattles around in my brain a bit.

Right now though, it looks like the break even point is around the two year mark if I can keep costs to about $3,000 all in. That's not bad at all.

The massively increased range, no electronics, no hard to obtain sensors, massive torque increase etc sounds good.

What are you doing for an alternator? I thought that our TJ's used the ECM to control charging.

 

[RustyAutoholicGuy]

Chris, you're killing me here...lol. It's in the wild-ass idea stage.

Grant, let me think on this a bit. I'm sure I'll have more questions once it rattles around in my brain a bit.

Right now though, it looks like the break even point is around the two year mark if I can keep costs to about $3,000 all in. That's not bad at all.

The massively increased range, no electronics, no hard to obtain sensors, massive torque increase etc sounds good.

What are you doing for an alternator? I thought that our TJ's used the ECM to control charging.

Yeah that sounds about right for the cost of the conversion honestly. I'm doing more . . . unique stuff with my build so mine is costing more. I'm at about a 18 ~ 24 month pay off period as well for the swap, though it all depends on what highway MPG I end up getting, it could less time or more time. Like @Chris has said though, even 25mpg would be a win but I'm honestly aiming closer for 35mpg :devil:

Actually @StG58 that is a fantastic question. So the serpentine kit/motor mount kit I'm using from KubotaSwappers is designed for an XJ Cherokee so I'm using the XJ Cherokee alternator and AC Compressor. I'm hoping my power steering pump will work with his setup, I think it will, but I should know for sure this coming weekend!

I need to do another video but work was stupid busy this week and the bad weather here this weekend on top of having my kids this weekend I just haven't had a chance to work on my project. I'm getting a ton of parts in this coming week so I will be posting more videos this week!!!

Thanks!
-Grant

 

[Chris]

Sell the supercharger and you can EASILY afford the Kubota engine and adapter

Honestly I'm so excited about the potential of a 30+ mpg TJ Wrangler. I still can't believe the MPG of my Liberty and I've owned it for 4 years and put 120K on the Liberty!!!

-Grant

Oh, I could... but to be honest, I really want to feel the insane power from that supercharger on this 4.0.

Plus, I'm admittedly attached to my 4.0 since I have the 42RLE transmission behind it as well as this RubiCrawler, which is the same as having an Atlas 4-speed but at less than half the cost.

 

[RustyAutoholicGuy]

Oh, I could... but to be honest, I really want to feel the insane power from that supercharger on this 4.0.

Plus, I'm admittedly attached to my 4.0 since I have the 42RLE transmission behind it as well as this RubiCrawler, which is the same as having an Atlas 4-speed but at less than half the cost.

The Rubicrawler and the 42RLE I completely understand!!! I wish I could have kept my 42RLE, I'm just utterly surprised there is not aftermarket TCU/TCM support for the transmission, it completely boggles my mind! You would think with the number of TJ owners AND the Rubicrawler there would be some support out there for it!

Now to throw a completely crazy thought out there if there ever is an aftermarket TCU for the 42RLE!

42RLE -> Rubicrawler -> NP231 -> NP231 :firedevil:

Just saying

-Grant

 

[StG58]

Wow, this is turning into a most excellent design exercise, if nothing else.

Intercooler size and design, gauge selection (running the tach off alternator output!?) The difference in shifter position between the AX-5 and the AX-15 (how far foreward can I shove the engine / transmission / transfer case assembly and still shift), radiator selection, mechanical or electric fan (s)...

Lots going on here. Love it. Can't wait for the next installment of your videos Grant!

 

[Chris]

The Rubicrawler and the 42RLE I completely understand!!! I wish I could have kept my 42RLE, I'm just utterly surprised there is not aftermarket TCU/TCM support for the transmission, it completely boggles my mind! You would think with the number of TJ owners AND the Rubicrawler there would be some support out there for it!

Now to throw a completely crazy thought out there if there ever is an aftermarket TCU for the 42RLE!

42RLE -> Rubicrawler -> NP231 -> NP231 :firedevil:

Just saying

-Grant

If you have an 05-06 model like mine (with the PCM and TCM as one module) you can get the HPTuners MPVI2 (https://www.hptuners.com/mpvi2/). That gives you 100% full access to the PCM to do anything from flash it with a new tune, change air fuel ratios, timing, disable emissions, and anything you can imagine... literally full access! I'll have to play around with it though and see if it allows any control over the transmission... that would be cool if it did.

Again though, that unit only works on 05-06 models.

I'm not sure what kind of crawl ratios you'd get with that setup... Hell, the RubiCrawler alone gives me a 10:8.1 low crawl ratio

 

[RustyAutoholicGuy]

Wow, this is turning into a most excellent design exercise, if nothing else.

Intercooler size and design, gauge selection (running the tach off alternator output!?) The difference in shifter position between the AX-5 and the AX-15 (how far foreward can I shove the engine / transmission / transfer case assembly and still shift), radiator selection, mechanical or electric fan (s)...

Lots going on here. Love it. Can't wait for the next installment of your videos Grant!

I will be posting a video Monday night, I just don't know yet what I will be doing completely I should have a ton of parts coming Monday pending this snow storm that is suppose to hit us . . .

If you have an 05-06 model like mine (with the PCM and TCM as one module) you can get the HPTuners MPVI2 (https://www.hptuners.com/mpvi2/). That gives you 100% full access to the PCM to do anything from flash it with a new tune, change air fuel ratios, timing, disable emissions, and anything you can imagine... literally full access! I'll have to play around with it though and see if it allows any control over the transmission... that would be cool if it did.

Again though, that unit only works on 05-06 models.

I'm not sure what kind of crawl ratios you'd get with that setup... Hell, the RubiCrawler alone gives me a 10:8.1 low crawl ratio

WHAT THE HAY @Chris . . . If you could please look into that would be amazing! I thankfully have not done anything to my wiring harness or ECU yet on my 2006.

So on my setup if I keep the 42RLE, install the RubiCrawler AND run a Double NP231 transfer case setup I would have a crawl ratio of 20.12 to one . . .

-Grant

 

[Chris]

WHAT THE HAY @Chris . . . If you could please look into that would be amazing! I thankfully have not done anything to my wiring harness or ECU yet on my 2006.

So on my setup if I keep the 42RLE, install the RubiCrawler AND run a Double NP231 transfer case setup I would have a crawl ratio of 20.12 to one . . .

-Grant

I'll look into it for sure. I ordered it, but I confirmed with the company who makes them that it has 100% access to the PCM on the 05-06 models. He said with the click of a few buttons on my laptop I can turn off my evap system, disable the post cat O2 sensors, change the timing, air fuel ratios, etc, etc.

The only question is the transmission, which I didn't ask about. I'll let you know if I find out anything in regards to the transmission.

I bought that module as it's necessary to tune the PCM for my supercharger.

The only issue you'd have with two NP231s is that that would definitely take up a lot of room under there, wouldn't it?

 

[RustyAutoholicGuy]

I'll look into it for sure. I ordered it, but I confirmed with the company who makes them that it has 100% access to the PCM on the 05-06 models. He said with the click of a few buttons on my laptop I can turn off my evap system, disable the post cat O2 sensors, change the timing, air fuel ratios, etc, etc.

The only question is the transmission, which I didn't ask about. I'll let you know if I find out anything in regards to the transmission.

I bought that module as it's necessary to tune the PCM for my supercharger.

The only issue you'd have with two NP231s is that that would definitely take up a lot of room under there, wouldn't it?

No not really, I'm already shoving the engine 6.5" inches forward and I was going to run an AW4 automatic which is a little over an inch longer than our 42RLE transmission, and I don't think the RubiCrawler adds any length so I should be fine still for adding a NP231 doubler setup!

I'm trying to read all the information on that HPTuner now and figure out what the Pro feature adds and if I even need it!!!

Thanks
-Grant

 

[Chris]

No not really, I'm already shoving the engine 6.5" inches forward and I was going to run an AW4 automatic which is a little over an inch longer than our 42RLE transmission, and I don't think the RubiCrawler adds any length so I should be fine still for adding a NP231 doubler setup!

I'm trying to read all the information on that HPTuner now and figure out what the Pro feature adds and if I even need it!!!

Thanks
-Grant

The RubiCrawler doesn't add any length, that's right.

You don't need the Pro feature, that doesn't give you anymore access to the PCM or anything.

 

[RustyAutoholicGuy]

The RubiCrawler doesn't add any length, that's right.

You don't need the Pro feature, that doesn't give you anymore access to the PCM or anything.

Ugh so now I'm in this weird catch 22, do I spend the $300 on this tuner and just custom configure my 42RLE which would also allow me to keep my cruise control or do I go to my manual shift AW4 . . . I have no idea what to do anymore . . .

 

[Chris]

Ugh so now I'm in this weird catch 22, do I spend the $300 on this tuner and just custom configure my 42RLE which would also allow me to keep my cruise control or do I go to my manual shift AW4 . . . I have no idea what to do anymore . . .

I’m not even sure if you can control the transmission with that tuner though. I know you have full control over the engine, but I never asked about the transmission.

 

[RustyAutoholicGuy]

I’m not even sure if you can control the transmission with that tuner though. I know you have full control over the engine, but I never asked about the transmission.

Well it looks like it's not actually but @Chris let me know if you discover otherwise!!!!

https://forum.hptuners.com/showthread.php?69623-No-trans-support-for-2010-Jeep

Thanks
-Grant

 

[Chris]

Well it looks like it's not actually but @Chris let me know if you discover otherwise!!!!

https://forum.hptuners.com/showthread.php?69623-No-trans-support-for-2010-Jeep

Thanks
-Grant

Ahhh, I had a sneaky feeling there wouldn’t be support for the transmission. That’s a bummer, but if I find otherwise, I’ll definfely let you know.

 

[Calvin.8]

Just curious, what do you think the top speed of this motor is going to be on your jeep. Not looking for racing but wondering about if it has the ability to go on the highway or interstate going 70-75 mph. If so this sounds like the perfect engine to swap! Increased torque, I think you said it was lighter as well, muuuuucchhh better fuel economy, can still be used on the highway, and best of all it is one of the cheaper swaps out there.