Starting a 4L Swap in the coming weeks. Could use help? San Diego

[suzq044]

It'll be the first swap I have ever done, I could use some help from people that are familiar with the process for our Jeeps. The engine is going into Levi to replace his 258 with the HO 4L. I have been looking at information online via some Wrangler pages (mostly YJ) and already have a couple questions.

Will I be able to keep (or should i) the oem 5spd already in Levi, or go with the XJ 5-spd? (it's a 1992 XJ Cherokee donor)

I have posted this on SCFSJ already; I am just looking for a place to do the work and some people that already know how to do it. We already have an engine hoist and stand. As I said though, I am completely inexperienced with this stuff. :eek: So the more help, the better. :fsj:

[addicted]

It'll be the first swap I have ever done, I could use some help from people that are familiar with the process for our Jeeps. The engine is going into Levi to replace his 258 with the HO 4L. I have been looking at information online via some Wrangler pages (mostly YJ) and already have a couple questions.

Will I be able to keep (or should i) the oem 5spd already in Levi, or go with the XJ 5-spd? (it's a 1992 XJ Cherokee donor)


You will need a metric bolt for the back engine side mount on the drivers side as they used that for a knock sensor on the older Renix 4.0's and never did anything with it after they stopped using the sensor in '91.

I would use the AX15 that is in the XJ and your NP208 should bolt right up to it. You might need to drill new holes in the crossmember but i'm not positive on that. You will also need to do something for the clutch master cylinder which might also lead to needing a hydroboost system. So maybe use the T-5 that is currently in there until you can get all the necessary parts to do the AX15 swap. But in doing that you will need to have the bell machined for the crank positioning sensor or use the $$$ one that Hesco sells that puts it on the crank pulley.

You will also need a fuel pump for the EFI system. I used the tank with pump and sender for my XJ powertrain swap. The XJ tank is about the same volumn as a factory GW cofffin tank and 5 gallons bigger than the J truck, but it will require you to relocate your spare tire. You could always go bigger with a Suburban tank as well.

I used this site for a lot of my info for wiring; http://www.cjoffroad.com/forums/forum.asp?FORUM_ID=24
Lots of good info on there.

[suzq044]

There's nothing really in there, I would need a complete how to.. lol - I am that much of a noob. I am putting this in a FSJ Cherokee, not a CJ.. Granted they'll be quite similar swaps. I am starting to get nervous about this. lol.

[addicted]

There's nothing really in there, I would need a complete how to.. lol - I am that much of a noob. I am putting this in a FSJ Cherokee, not a CJ.. Granted they'll be quite similar swaps. I am starting to get nervous about this. lol.

There is plenty in there, the hardest part is the wiring and the 5 wires you need to make it fire are the same for all the '91-'95 Jeep XJ's and YJ's with the 4.0 with exception of the colors. Yours is going to be fairly simple since you are going with a manual trans, no auto trans stuff to weed out or get working. When searching cjoffroad.com use these words; which wires for fire. They will weed out a lot of the threads that don't pertain to your swap.

The mechanical aspect of it is just labor and wrench turning, if you can handle that then you can do this swap. Just take your time. The best info I can offer you is to get factory service manual type wiring diagrams for both vehicles. www.alldatadiy.com (http://www.alldatadiy.com) is a really good resource. I used it to get the wiring diagrams for the '93 XJ electronics I put on my '97 XJ powertrain that I swapped into my '89 GW.

This is how I suggest you go about the swap and mostly how I did mine.
1) Take lots of pics of your current engine bay.
2) Disconnect all the wires and mark what they are for with some tape and a marker now either disconnect the harness from the bulk head and set it aside or just move it out of the way and drape it over the drivers mirror.
3) Pull the powertrain from the FSJ and set it aside. (I like to pull it all bolted together that way i'm not wrestling under the Jeep on my back with heavy parts coated in grease)
4) Now take pics of the XJ engine bay.
5) Disconnect the bulkhead wiring for it, separate the two halves one side is for the headlights and stuff the other for the powertrain and unbolt the PCM from the fender and any other places it is attached, marking what they are for if it isn't obvious and you may forget and place it all on top of the engine leaving everything you can still connected to the powertrain. Doing it this way makes it far harder to know where everything goes and routing it in the FSJ engine bay.
6) Remove the powertrain from the XJ
7) Clean the engine bay and undercarriage of the FSJ, unless you don't care how it looks. You might want to powerwash the XJ powertrain before getting started as well.
8) Swap the FSJ transfer case onto the AX15 unless you have chosen to keep the trans and transfer case for the FSJ in the FSJ to help with simplicity.
8a) Now is a good time to seperate the engines and transmissions and make sure the clutch and flywheel is good on which ever transmission you have chosen to go with.
9) Take the engine side mount off the FSJ engine and open the back hole up to match the size of the metric bolt that will be needed to bolt it to the block.
10) Put the pieces back together and install the powertrain into the FSJ
11) Install the various hoses and such onto the 4.0
12) Lay the wiring out into the FSJ engine bay, it should be similarly laid out to how it was in the XJ.
13) This is the part where you need to really take your time and having the proper schematics and pin outs is necessary. You need to mark each wire with tape at the bulkhead and then cut them off after they have been marked or you know what the wire does and cut it off then mark it, doing it one wire at a time. Then do the same for the FSJ's harness and match them up.
13a) Depending on what your FSJ's gauges require for resistance for the proper reading you might be able to hook them up directly to the wires from the XJ's sending units and they will work properly. That was my experience with my '89 except for the fuel gauge.
14) If you are keeping your factory tank and sending unit you will need to plumb in an inline fuel pump and wire it up the the XJ's harness.
15) fire up the engine look for leaks and enjoy!

*Disclaimer* There are going to be some things that aren't listed, like if the AC systems work you will want to have them evacuated first. You will need to do a hydroboost conversion and plumb that in.
I am assuming your Jeep is pre Chrysler with the round gauges and amp meter, you will want to convert that over to a volt meter if you are going to run the XJ accessories, such as the alternator. The best way to make the connections for your wiring is to solder and cover them with heatshink tubing. I suck at soldering so I use heatshrink buttconnectors, some people will say they aren't good but if done properly they will last and work just as well. I have used them for years without issue.
If you stick with the AX15 in the XJ (highly suggested)you will need to mount the master cylinder on the firewall next to the hydrobooster.
There are going to be various other little things that I forgot to list and always come up when doing a swap like this but it's all part of the fun and can be overcome and avoided by taking your time and researching.

Just remember to take your time and if you get frusterated to walk away and come back when calm.

[suzq044]

Cancelled plans for now. I have nowhere to work, but the truck was ideal for our situation; but without somewhere to do the swap i'm ****ed.

[addicted]

Yeah, having somewhere to do a swap that involved is pretty important.

[suzq044]

Yeah; I'm not "allowed" to do it in my own garage, thanks to the HOA. I cannot wait to leave this fricking neighborhood.

[addicted]

HOA's suck and it sounds like yours goes by the HOA bible to the T. Mine has just been started andnone of us seem to care what the other neighbor does as long as it's within reason for a normal neighborhood without an HOA. Heck i've parted 4 Jeeps in my driveway and all of them have sat at the top of it as they've been parted slowly and then waited to be hauled off as just a shell for weeks and I am the second house in the sub so everybody has to drive by me and haven't gotten one complaint yet.