First off, the Jeep is a 1993 Wrangler YJ with the stock 2.5 four cylinder and AX5 5 speed transmission, which has been lovingly named 50 Shades of Black. It has 147,000 miles and counting, 17,000 of which I've put on it since I got it a year and a half ago. It's had a hard life before me, it has a fair few leaks that I will be taking care of as I go. The main reason for doing the swap is to gain fuel economy, power, and reliability. Right now, it's getting about 19 mpg on the highway, doing 60-65mph, which does nothing more than impede traffic. If I try and hit 70, fuel economy drops to about 17ish mpg, and I'm turning about 3000 rpm (it has stock 4.10 gears from the factory to compensate for the lack of power). Which brings me to my next point, power. While not terrible, the lack of power is apparent on the highway. Around town, the four banger does great, as long as you leave like John Force at stoplights to keep up with traffic :grinpimp: I have gotten used to it, though, which is why the whole "oh, the Kubota doesn't have a lot of power, it needs a 4bt" argument is invalid. Granted, I did consider a 4bt for a long time, but the price of the motor, adapters, and all the suspension work and driveshaft work I would need to make it fit made impossible to afford. My original plan was to get another 2.5 and build it to handle boost and run about 10 psi through it, but the cost of that and a custom standalone ECU and then finding someone to tune it would cost as much as a diesel swap, if not more, and would reduce the reliability and drivability of the truck, especially since the price of gas in Jersey just went up 20ish cents Which brings me to my final point, reliability. I work around diesel trucks at the nursery I work at, my dad is a diesel mechanic and used to be an O/o, and I have a friend that is going to school to be a diesel mechanic and is currently putting a 7.3 Powerstroke in a Bronco, so I'm surrounded by diesels and I understand the reliability and overbuilt nature of them. The turbo 2.5 I could have built to be reliable, but it would have cost way more than it was worth, and would have been the same amount, if not more than the cost of a diesel, and wouldn't have been as reliable. I am confident in the Kubota's ability to hold boost, as multiple people are running these motors with boost reliably in a daily driver platform, which is the plan for my Jeep, with a bit of mild trail running.

 

The motor I plan to run is a Kubota V2203 out of a Carrier reefer. A friend and I pulled the motor out of the trailer a week ago and it looks brand new. All the fluids were clean, and there were no leaks. The battery was dead, so when we jumped it to get the engine hours, the only number we found was ENG 60, which leads me to believe that there is possibly only 60 hours on this motor, which is also partially confirmed by how clean the fluids are, and that all the bolts on the backside of the bell housing were missing, like the swapped engines and left the compressor in the trailer (the compressor has some leaks, so that's definitely not new). I plan on running either a K03 turbo or a TD04 (03?, not sure on the number), and either build an adapter for the manifold, or run a turbo manifold off a 2403. Oh, the nuts holding the exhaust pipe to the manifold also spun off with a wrench and weren't rusty or crusty, which also leads me to believe that the engine has low hours because the exhaust itself was kinda nasty (going off my experience of working on gas engines, if the exhaust has been on the engine for awhile, good luck getting those bolts out). I may be wrong, as I'm not the most experienced with thus stuff, so any input is greatly appreciated. Oh, and the intake manifold was really clean, which i believe means there's no to little blow by, it's hard to tell from the picture.

Also, if anyone is looking for a Slurpee holder, the medium paper cup fits perfectly between the studs on the exhaust manifold

 

Okay, enough of me yammering on, here's the plan:

Kubota V2203

Turbo- K03 or TD04 or TD03

Exhaust- either a V2403 manifold or a turbo adapter

Oil pan- either a Bobcat bread pan oil pan with a baffle welded in around the pick up tube, or a custom oil pan like what's in a car, and an extended pick up tube

Valve cover- drill and tap for oil fill plug and run a tube for the vent

Intake manifold- plug vent port

Gaskets- replace as many as possible, as well as replace the oil pump while I have the front cover off

Adapters- I'm going to make an adapter to adapt the SAE 4 flywheel housing to a GM 60 degree V6 bell housing pattern and make a flywheel adapter to turn it into a Jeep crankshaft

Wiring- cut out everything that isn't sensor, alternator, or starter related. I want to retain all the Jeep parts (except the starter) to keep the computer happy so I have gauges

Fuel- drop the tank and pull out the fuel pump and put in a pick up tube and an extended return so the fuel isn't splashing everywhere in the tank (not sure if it matters) and run hard line along the frame up to the fuel filter, and then a soft line from the hard line to the fuel filter to minimize vibration fatigue on the lines

Accessories- make a mount for the alternator (probably on the drivers side, since that's where Kubota mounts there's), and extend the factory wires. Not sure if I will keep power steering and make a mount, or just leave it out. I also need t make a mount to run a vacuum pump to run the vacuum doors on the heater box and the power brakes (possibly an Isuzu NPR alternator/vacuum pump setup)

Throttle set-up- I'll need to make some sort of mount to hook up the throttle cable, I read somewhere the Bobcat throttle cable mount can work. If not, I'll make one

Motor mounts- I plan to make mounts similar to Redveloce's that use the stock Jeep frame mounts (the four cylinder mounts are slid back on the frame rails, which puts them closer to the centerline of the block). I'll insert a picture, tell me what you guys think. I also plan on running a set of aftermarket rubber motor mounts as mine are getting worn out, and I'm going to have access to them, so why not.

Fuel cut off- make a block off plate for the solenoid and run a cable for the manual shut off as a form of anti-theft, as well as an emergency cut off in case there is ever a problem, and it's one less wiring thing to go wrong

Cooling- stock radiator (same part number for the 2.5 and 4.0, so there's more than enough cooling capacity for the motor, which is 2.2 liters) and an electric fan for clearance, and because the Carrier didn't have a manual fan, as well as an intercooler to keep intake temperatures down (not sure if that will be part of the original build, or if will happen later on).

Transmission- upgrade to an AX15 using a Dakota bell housing that has a GM 60 degree bolt pattern on one side and the big face transmission pattern on the other, as the AX5 has a habit of exploding behind the stock 2.5, and the trans is on it's way out now as it is, so it will be upgraded when i put a clutch in the Jeep over the winer/early spring. The transfer case will be the NP231J with a SYE kit to help with driveline angles (not required for the diesel, but will be helpful when I put my 2 inch lift in and swap rear axles). Clutch set up will be the stock 2.5 flywheel and pressure plate with a clutch dick from an 84 Camaro 4 cylinder 4 speed, if I remember correctly. I may put in upgraded parts for more holding strength, not sure yet.

Axles and gears- I plan on running 31s and either a 3.07 or 3.23 ratio to keep cruising rpm's down. If anyone knows a good cruising rpm at about 7-75, let me know so I can adjust my ratio's so the motor is laboring or being overworked. I plan on either swapping in either a Ford 8.8 or Toyota 8 inch, as the Dana 35 also has a habit of blowing up behind four cylinders and anything more than stock sized tires.

I'm sure I'm missing stuff, let me know if there's anything else I need to look at. thanks for taking a look at my build.

Joe

 

Hey Joe, nice score on that motor! You asked about cruising RPM, these motors are happiest at 1900 RPM-2100 RPM. If you are going to do a transmission swap anyway you might look at upgrading to a 6spd like I did. I am running one from a 2008 Nissan Frontier, it's perfect for this motor and gives me better gearing than the 5spd did. Wranglers came with 6spd's. I am also using a turbo manifold, but mine is off the V2003, it fit my build better than the V2403 manifold, I think Red is using it as well.

 

Hey FTE, thanks. I can't believe the guy was just giving it away. Super nice old farmer guy.
Okay, so between 1900 and 2100. So at 2000 rpm with 31s and a 5th gear ratio of .75 and a gear ratio of 3.53, I can run about 70mph. 2100 is right at 74-75ish. So those are the numbers I need to be around.

I looked at the Wrangler 6 speed. I ruled it out because they're way too expensive, the bell housing is integrated into the transmission, so I need to design an adapter that will only work with that, and they have a lower torque rating than the 5 speeds. And parts are hard to get for them. I think there's a guy on a 2.5 forum that made an adapter to put one behind a 2.5 like what my Jeep has right now, and he doesn't like it. Or rather, the Jeep doesn't like it. 6th gear is too high to keep the engine in the power band. The AX5 that came with the Jeep has an overdrive ratio of .85 :flushed: They like to run at about 2600-2800, making peak torque right at 3,000. Also, I just got the parts to convert my bell housing to an external slave set up since the internal is giving me problems and the pressure plate is pretty worn out (pedal gets really light if I shift at anything higher than 2500-3000, for anyone that has driven one of these Jeeps, that's the minimum you need to shift at to halfway keep up with traffic). So I need to stick with the 5 speed for now. I did read of a few people running the AX5 with the VW diesels and they were surviving, and a guy with a Firebird and a Yanmar (yeah, that's an interesting combination) with the weakling NV1500 and he said it has stood up to all the abuse he has put it through, I think if I keep the power level respectable and ignore the fact that I'm 20 and will therefore try to drive with my head firmly inserted in my butt, I might be able to make it live long enough to get an adapter plate for the AX15 and find one of those and swap it in. I just have to make it live to get me to and from work and school.

As for the turbo manifold, I'll have to look around to see if I can find one. I know Parts-Barn has a 2403 manifold, never looked for a 2003 manifold.

I will hopefully be getting the engine running this weekend, midterms have been taking over my life completely and then it was 30 degrees last weekend, and the engine is sitting outside (in the body of a Bronco to protect it from the elements), so yanking that out and trying to make my fingers work wasn't happening. I'll put up a video when I can.

Joe

 

Parts barn also has the 2003 manifold, that's where I got it from.

 

Is it a 2003? The only one I've seen was just listed as an 03, so I assumed they were all the same.
https://parts-barn.com/index.php/ku...kubota-genuine-parts/kubota-v2203-exhaust-system/03-turbo-exhaust-manifold.html
Are the holes in that flange tapped for bolts or studs, or is the turbo supposed to be through bolted?

Joe

 

That's the manifold, I have the motor in the barn that has this manifold with a TDO3 turbo. You will need to make a turbo adapter for the KO3. Even though it's from a V2003T it has less restricted ports/runners than the Carrier manifold or the V2403t one.

 

Made some progress with the motor yesterday. I got the compressor taken off as well as the high idle solenoid and any other random wires that were floating around. We bled the IP, all the injector lines, as well as the fuel filter and it refused to light off. It got to the point where every compression stroke was making a small puff of smoke and every once in awhile two cylinders would try to fire quickly, but it still wouldn't light off. The starter wasn't spinning fast enough. I'm going to try and take it apart and get a rebuild kit for it today, so hopefully I can get it fired up this weekend.

Oh, and anyone trying to start one if these motors outside of a trailer, that shut off solenoid has to have power. We were trying to start it and bleed the lines with the solenoid not letting fuel by. Thanks for the assist in that one, FTE. I plan on making a block off plate for that later on, so I just cut the rod off the solenoid and put it back on so there wasn't a hole in the front of the gear cover. If you want to wire it to actually work, the red wire goes to power, the black to negative, and the white wire goes to the wire coming off the starter with the funky looking round plug. I believe that wire is also white.

Joe

 

Got to work on the engine today.

https://youtu.be/FZ6W3fbGfik

It's....ALIVE!!
I made battery cables out of some 4AWG wire and regular ring terminal connectors and it fired right up. Didn't even complain about me using no glowplugs, and it was probably around 38 degrees. No knocks or ticks or anything. The smoke is from the raw fuel in the cylinders left over from trying to get the engine started last weekend, and soot water. Condensation ended up forming in the exhaust manifold from the three straight days of rain we got, so there was a nice big puff of soot and smoke on start up, but it cleared up quickly. I started it again after the video ended and almost all the smoke was gone. I made sure to run it less than a minute in total, since there's no water flowing through the block. Next step, turbo time!

Joe

 

Congrats Joe, it's a good feeling when you get it fired the 1st time isn't it?

Jeff

 

Thanks Jeff. You have no idea how long this week has been waiting to finally be able to get to mess with the engine again. Last weekend was such a let down when it wouldn't start. Having it light off instantly was incredible. Next step is to find a turbo and get an adapter made and swap oil pans and probably the exhaust manifold and adjust the springs and the shims in the injection pump.

Joe

 

Updates

Okay, update time. I've been super busy with school and now work so I haven't made too much progress. I finally got the engine on a stand and started gathering more parts. I picked up a 2403 turbo manifold which will keep the turbo close to the engine and away from my clutch and brake reservoirs, a power steering pump so I can start making a mount for that, a few gaskets, and a trans and bell housing. I've decided to go with a Ford NP435 mated to an Early Bronco Dana 20 transfer case, which will make for a super strong and short drivetrain. And for overdrive, I'm going to start saving my pennies to buy an Advance Adapters Ranger Torque Splitter. For anyone that doesn't know, the Torque Splitter is a two speed auxiliary transmission that mounts between the engine and the transmission, with 1:1 and 1:.72 ratios, giving me a 27% overdrive in every gear, and turning my four speed into an eight speed. The main perk is the super low overdrive, as compared to a usual five speed with a .75+ ratio unless we get into the oddball T5 ratios, and the abundance of gears to keep the engine in it's power band and help with the giant drop between 3rd and 4th gear. And swinging two sticks in a Jeep, for that added cool factor. The whole set up should be about the same length as an AX15 NP231 set up, but infinitely stronger.

As for adapters, I was talking to FTE and he showed me his set up in his Jeep, which was to bolt the Jeep 4.0 bell housing right to the flywheel housing. AMC was kind enough to make a bell housing to bolt Ford NP435 and T18 transmissions to a 4.0 (technically a 258, but close enough), so I started hunting for one..which ended quickly with me realizing those are worth their weight in gold. So I picked up a bell housing out of a CJ7 that bolts a Ford T5 to a 258. And because AMC liked to recycle parts, all the bell housings are the same, just with different holes drilled in them, and the holes are already center punched. :smokin: I still need an adapter for the flywheel, but one step at a time.

 

Adapter Plate

Joe,
I started this same build in 2013. I finally completed in 2015. Although the actual build was completed in 2014, I kept melting my motor down. What I found in my experience is that don't mess with the injector pump and never add the water and methanol injection. Keep your RPM's where they are. The main problem with this build for me was 3rd to 5th gear. The Jeep rarely made it to 5th gear and when it did the EGT's skyrocketed. What I found is if you leave everything(fuel adjustments) alone and change your gearing you will have long-term success. I started with the AX-15 and 3.73 gears. I jumped the gears to 4.88 and had good success with still great fuel economy. The drawback here is that the Jeep will only go a maximum speed of 52 mph. If I change the tire size from 35's to stock, this would be better. I plan to change the gearing one last time to the 4.56. This should put the Jeep at legal highway speeds (60-65) and still allow you to climb small hills in 5th gear. Right now it's great for town and mudding, but not real effective for a daily driver. This was just my experience and what I learned, there are people on here much smarter than me.

If I can figure out how to attach drawings and pictures on this I will include a complete drawing of an adapter plate that you can send to your machine shop. I did not come up with these drawings but did use them with complete success. I want the recognition to go to the person that was kind enough to post these for free and will include the original link. My adapter plate cost $550 and was made of 1" thick aluminum. I used the 4.0 starter and flywheel as well as a stage 3 clutch. Best of luck and let me know if I can help.

It won't let me post an outside link because I have not been here long enough. I will reply to you with this link, once I am able to do so.

 

Some more updates, I picked up an NP435 four speed trans out of a 66 Ford F250 and a Dana 20 transfer case out of a late 60s Ford Bronco. I also got a bell housing out of a CJ that had a 258 and a T5, which is the same bell housing for the 435, minus the bottom holes. I also started working on the adapter pattern on CAD. I'm having a friend 3D print it to check my measurements and then I'll start working on the flywheel housing.

 

Another update after an uneventful summer. I spent most of my time trying to get a 54 Chevy 1 ton trying to run after it sat for 10 years as an early retirement/father son project, but that's a different story.

I picked up a new turbo, had it shipped from across the pond. It's an IHI RHF5 VJ33 off a 2.5 Ford Ranger. Seems to be in pretty good shape, and it was cheaper than a new eBay China clone, so I can't complain. Only problem is I can't get the bolts out of the compressor housing, gotta love Torx bits. I took a couple pictures comparing the VJ33 to the K03 and they're close in size on the hot side, the VJ33 looks to be maybe a tiny bit bigger, and the exhaust housing looks like it would flow a lot more than the K03 housing. If anyone is looking for a K03 to use as a parts turbo or a mockup, I'll be selling mine. I also have a downpipe flange to go with it. I also have it sitting on a 2403 turbo manifold and the pattern is close, but not the same. If anyone has a side exit manifold, I'm looking to trade mine for it as the turbo is set up perfect for a side exit manifold.

And today the Fedex guy dropped off one of the big pieces of the puzzle, an oil pan and pickup tube and all the required bolts for an L4200 tractor. Bolts right on and has a dual sump pan with a deep pickup tube to help prevent oil starvation at odd off camber angles. I also picked up a governor spring from the same tractor since based on what I've read they rev out to between 2800 and 3000rpm.

 

Question for everyone, what size drill bit did you guys use to drill the hole for the dipstick tube/turbo drain. I found one guy said he used a 29/64th bit, just checking to make sure.

Also, does anyone know the torque specs for the aluminum oil pans? Even for the Carrier pan, I haven't managed to find the specs online.

Final question, how did everyone add an oil fill to the valve cover? I've seen a couple different ways: rubber plug, JBWeld a big nut on and use a bolt, add an actual quarter turn fill cap. I haven't been able to locate a factory valve cover with an oil fill, so I was thinking about using the big bolt and nut method.

Thanks,
Joe