1999 Jeep Wrangler 2.2L Kubota diesel swap

[redveloce]

Have you given any thought to the mounting of an AC system in it?

Yep, I'll probably do it at some point. All of the stock stuff will work for the Jeep except the compressor. For that I'll need to make a custom bracket, but that's not any bigger deal than any of the other brackets I've had to make. I picked up a crank pulley from a wrecking yard last year, and a friend made an adapter for the Kubota crank pulley for me. I think the crank pulleys were off of an early Nissan Pathfinder, but I just walked around until I found one with a lot of pulleys that looked like what I wanted. I wanted to be sure to have as much expandability as I would ever need!

Here's the stack with the Kubota pulley on the bottom and the aluminum adapter between it and the Nissan pulleys.

Sam at https://parts-barn.com/ has been an amazing help with parts, and has been posting parts helpful for these swaps on the site. They have a two groove crank pulley available now, which should be more than enough to run all of the normal accessories. Being a tractor shop, they also have a lot of used parts and spares, so if you need something it's always worth calling him.

Also, hypothetically of course, lets say I wanted to call up the shop that made the transmission mount plate you used, would they be able to recreate it/ adapt it for the NSG370?

A friend with a home machine shop made the adapter for me. It was a huge job for him, so he's not interested in making any more, but I have all of his CAD drawings available (with his permission) if there's a local machine shop that you could have do the work.

 

[Krytos]

Thanks bud, I might bother you for that information one day, provided your friend is ok with it.

Appreciate the response, and in all seriousness this has been one of the better build threads I've ever followed. Thanks for keeping it up to date.

 

[Jeep]

Thanks for the info on getting the tach to function, I swapped a 3.3 Cummins into my TJ and had all the wiring figured out from the diagrams, but didn't realize the cam signal need detection, I have the stock trans and flywheel so the crank signal is "factory". Just to clarify you tied the crank signal wire to the cam signal wire via relay but only while cranking, correct? I'm also using the factory fuel pump wiring to run the lift pump, as well as all the gauge functions through the factory ecu. As far as I can tell everything should turn on as soon as it sees the crank signal, I haven't fired it yet but real close to doing so.
Thanks again, I didn't expect to see such positive results from such a small diesel, was sceptical on the 3.3!
Mark.

 

[Dan Grec]

Thanks for the info on getting the tach to function, I swapped a 3.3 Cummins into my TJ and had all the wiring figured out from the diagrams....

(Thread hijack)
Do you have a build thread or more details? I'd love to read more.

Thanks,

-Dan

 

[redveloce]

Thanks for the info on getting the tach to function, I swapped a 3.3 Cummins into my TJ and had all the wiring figured out from the diagrams, but didn't realize the cam signal need detection, I have the stock trans and flywheel so the crank signal is "factory". Just to clarify you tied the crank signal wire to the cam signal wire via relay but only while cranking, correct? I'm also using the factory fuel pump wiring to run the lift pump, as well as all the gauge functions through the factory ecu. As far as I can tell everything should turn on as soon as it sees the crank signal, I haven't fired it yet but real close to doing so.
Thanks again, I didn't expect to see such positive results from such a small diesel, was sceptical on the 3.3!
Mark.

Oh man, you have to show us this! I originally wanted to go with a 3.3, but couldn't find one. It should be great!

You are correct about how I have the crank and cam signal wires connect together while cranking with a relay. I've been thinking about it lately, and I don't see why it needs to disconnect at all. The signal voltage is the same, and I can't see the wrong signal causing any more of an error than getting no signal when it's disconnected. I'm going to do some playing around, it would be much easier if the relay isn't required.

I have the rest wired up exactly the way you do. Are you using the factory alternator? I did find that the PCM would sometimes get cranky, throwing a 'check gauges' light and zeroing out the volt meter when I was using an external voltage regulator instead of letting the PCM regulate.

As an aside, I've noticed while connecting directly to the PCM that the gauges are more of a relatively close estimate than exactly what the PCM is reporting. The tach on mine shows about 50 RPM more than the PCM, and the temp shows probably 10 degrees higher.

 

[Jeep]

I decided to use a big Delco industrial alternator and I'm just using the key on power wire to excite the field through a diode, I am hoping the voltmeter will function, a local auto electric shop does this often with good results and I just love the reliability of the old Delco's, plus the Cummins has "B"series pulleys and I can get the proper pulley on the Delco. I'm quite certain I will be disabling the check engine lights! It's not only the Jeep that has wonky gauges as far as accuracy, the Dodge trucks do the same thing. I have a build thread that I throw some stuff on once in a while, there's some good stuff on the adapter and some suspension fab, the Jeep is almost done right now, thanks for the info, saved me some headaches.

http://www.pirate4x4.com/forum/expedition-vehicles/1373650-respite-4-a.html

 

[redveloce]

I'm quite certain I will be disabling the check engine lights!

http://www.pirate4x4.com/forum/expedition-vehicles/1373650-respite-4-a.html

The voltmeter should function as long as the alternator doesn't let the charge drop below the PCM's low threshold for too long before it picks up and starts charging again. I don't know what that threshold is, but the external Chrysler regulator I tried using let it get too low before cycling. I hope the Delco alternator works out, that would save people a lot of hassle!

My CEL is minus a bulb. The light I'm referring to is the 'check gauges' light that comes on when there is a gauge fault or something pegs. It's accompanied by a beep.

Someone needs to set up a wiki or something where we can dump TJ conversion information.

 

[redveloce]

Here's one for anyone looking to do a diesel swap into a '97+ Jeep.

In order to turn on the tach, the PCM needs to see a signal from the cam sensor on startup. It's common for people to make or buy two sensor wheels, one for the cam and one for the crank sensor ($400+ from JD!). When I was building mine, I found that it doesn't check for accuracy of the cam sensor signal, just presence during startup. Some have used a relay to tie the disconnected cam sensor signal wire into the active crank sensor signal wire during startup, which is what I did and have used successfully for the past year and a half.

I was thinking about it last night though and couldn't see any reason why the cam sensor would need to be disconnected after starting. The actual signal from the cam sensor is used with the gas engines for checks related to fuel and ignition timing, but does not affect the gauge readout in any way after startup. It shares the same 5v power and ground output as the crank sensor, and is the same type of pickup, so there isn't any chance of overpowering and frying something.

I decided to try just directly connecting the cam signal wire to the crank sensor signal, and it worked! I managed to eliminate two fist fulls of wire, ties, and other junk in the process.

 

[Dan Grec]

In order to turn on the tach, the PCM needs to see a signal from the cam sensor on startup.

What signal does the tach actually use?
Is the cam sensor actually driving the tach, or is it just needed to fool the PCM and the tach gets it's signal from somewhere else?

If it's just to fool the PCM, I've always wondered why people go the mechanical option (like JD) instead of just wiring in an all-electronic box with a micro controller that makes a sine or square wave at some reasonable frequency (i.e. you know idle rpm, you can get roughly that frequency easily enough). I've seen tons of guys do this in other conversions, and it's nice and simple and removes the mechnical solution of an actual wheel and sensor that can be gummed up/etc.
Something like http://www.maplin.co.uk/p/function-generator-kit-n42fl - there are tons of options online that you seal in a waterproof box and forget about.

-Dan

 

[redveloce]

The tach uses the crank sensor, so reading the tach sensor is just to fool the PCM at startup. The PCM doesn't actually care if the signal is correct, so it makes more sense just to hook the cam signal wire into the crank signal wire. No extra hardware needed, and it works.

 

[Dan Grec]

The tach uses the crank sensor, so reading the tach sensor is just to fool the PCM at startup. The PCM doesn't actually care if the signal is correct, so it makes more sense just to hook the cam signal wire into the crank signal wire. No extra hardware needed, and it works.

Ahh, gotcha. The crank is actually needed and must be accurate, it's the cam that can be made up.
Makes perfect sense.

Nice work on making your swap even simpler and cheaper.

-Dan

 

[redveloce]

Thanks! The gauges are the only reason why I've kept the stock PCM at all. I've considered building an Arduino DAQ and using a tablet for the gauges, but I didn't want my mileage to get out of sync. I just picked up a ROM burner though, so now I can fix the odometer if I pulled the cluster and ever wanted to put it back. Ideally I'd sniff the CCD bus that runs the cluster and figure out how to emulate that, but that's probably deeper down the rabbit hole than I want to go.

 

[Dan Grec]

Thanks! The gauges are the only reason why I've kept the stock PCM at all. I've considered building an Arduino DAQ and using a tablet for the gauges, but I didn't want my mileage to get out of sync. I just picked up a ROM burner though, so now I can fix the odometer if I pulled the cluster and ever wanted to put it back. Ideally I'd sniff the CCD bus that runs the cluster and figure out how to emulate that, but that's probably deeper down the rabbit hole than I want to go.

It's a pain the gauges are control with such a complicated setup.
I'm going to have to cross this bridge when I jump into my planned JK swap, and I'm hoping to keep it as simple and straightforward as possible.

-Dan

 

[redveloce]

About a month ago I started having a horrible 'ball bearing in a coffee can' sound coming from the bellhousing. My buddy with the Ranger had his clutch come apart a month earlier, so I thought I was having a similar issue. I had already decided that it would be a good time to do some upgrades and fixes that I've been wanting to do for a long time, so I started to tear it down to pull the engine. The last thing that I pulled was the exhaust under the transmission, and that's when I found the broken exhaust bracket that was causing all of the noise to begin with (DOH!). I just altered the plan and left the engine in the Jeep while I did the upgrades, which ended up taking about 3 weeks longer than I had planned.

Since my next project will be a sports car, I wanted to test out some of the ideas that I want to use on that project. The things I changed are:

• Switched to a water to air intercooler
• Replaced the belt driven power steering pump with a Volvo electric power steering pump
• Added a fluid harmonic damper
• Relocated alternator to the opposite side of the engine
• 3" exhaust straight back on the driver's side
• Lots of custom fabrication!
• A lot of little things, like turbo drain routing, dipstick, etc

It's running, but I still have a few things to tie up before I can drive it. It should be back on the road tonight!

New exhaust. I'm going to run it for a while to make sure it works as planned before cleaning it up and having it ceramic coated.

Volvo power steering pump.

The heat exchanger should have plenty of cooling capacity!

The rest of the pictures are from when I stopped for the night last night.

 

[SamM]

Very nice! I want to build one myself. However, I want mine to be a Brute pickup with Toyota Minitruck axles and an R151F transmission. Already have those parts plus a rear full-floater axle kit from Front Range Off-Road. These were leftover from my Toyota FJ-40 Land Cruiser days.

SamM