Cherokee 4.0 engine swap to CJ-5?

Has anyone put a 4.0 liter into a CJ-5? I have a 1974 CJ-5, and access to a smashed Cherokee. The fuel injection, and extra horses would be helpful at the altitude in Colorado. I'm looking for any info on problems that I could run into; will it fit? Will it "bolt on" to the tranny? What about wiring?
Any ideas are appreciated.

 

If you have a 232/258 then your current bellhousing should bolt up to the 4.0. The only problem is the crank position sensor. On the Cherokee and Wrangler that mounts to the top of the bell housing. You can machine your bell housing to accept the sensor or you can use the CPS relocation kit from Mopar that puts it up front. I am not sure about all the wiring but this has been done before.

Also you will need an inline high preassure fuel pump for the fuel injection. The 4.0 runs at 45 PSI at the injectors.

 

If you have access to the smashed cherokee donor,,,and are patient enough,, you can salvage and use the factory wiring harness and connectors, etc, as well as the fuel pump, etc. Can be done if you research it out and are patient. You'll love having FI.

 

This is a swap that I am going to be doing if the future as well.
Does it matter if the donor is and auto or stick besides the obvious flywheel difference? And is the CPS absolutely necessary? What about the pilot bearing, motor mounts...? What year Cherokees are the best donors?
Will the same radiator be able to be used? Baffled fuel tank? There are a lot of little details I believe that should be fleshed out.

I'll be watching this thread.

 

Just something to look at, I almost had to buy a ECM for my '98 XJ and it was tranny specific. Don't know what the ECM looks at in the tranny, but a dealer could tell you.
And yes the CPS is necessary, the engine won't start without it. Somebody correct me if i'm wrong, I think it tells the ECM something about which fuel injector to fire.

 

they sell stand alone 4.0 liter wiring harness. I forgot the place that does.

DO IT, we will watch and eg you on!

 

I put a '95 Cherokee 4.0 into my '83 CJ5. I modified my T176 bellhousing for the CPS. Simple bracket and mod. I grafted in a '93 Wrangler harness(could have used the XJ harness) and used the XJ's auto computer. I bought a NAPA replacement Wrangler fuel pump and mounted it on the rear cross member. You need a VSS for a '91 Wrangler so it has the speedo cable and wiring. I had to lengthen my lower clutch rod about an inch for the clutch to work properly.
'91-'95 Cherokees are the best donors as they are OBD I and have the MPFI. You do have to swap to a YJ water pump. I also swapped on YJ alternator brackets. Use a YJ or later serpinetine CJ fan(water pump spins opposite on a serpentine engine).

 

As I said I used a '93 Wrangler harness so the wire colors I'm about to mention might be different on different year YJ or XJ harnesses. A factory service manual for the donor harness/vehicle is a must. O.K. so with my '93 harness I did the following: Red and black wire(10 ga) from YJ harness to Red wire(10 ga) on CJ bulkhead(this is the wire that originally picked up power from the solenoid on the CJ), yellow and white wire(about 16 ga) from the YJ harness to the red(about 14 ga) on the CJ bulkhead(switched power). Yellow wire(16ga) from the YJ harness-wasn't in the harness where the FSM said it was, turned out they moved the wire, due to a salt issue,to the harness going into the firewall to the left of the master cylinder as you stand at the radiator('93 specific, was in the supplement manual I didn't buy-I wouldn't have looked if I did buy it) to the light blue wire(14 ga) on the CJ bulkhead(crank-to-start). I pulled the brown/white wire from the YJ harness where it goes to a plug for the tranny and grounded it(nuetral safety switch). I swapped the CJ oil pressure switch with the XJ one. The tach wire is grey/light blue and the MIL(check engine) wire is black/pink.
On the original CJ engine bay harness I kept these wires: heater, back-up lights/4wd, oil pressure, water temperature, brake proportioning switch, WS washer, and lights. There was a big pile of wires I eliminated along with the computer for the BBD which you '74 won't have.

 

I ended up trimming off the ends of the CPS. The end of the CPS is approx. .020 from the 4.0 flywheel. Centerline from the sensor is 2.425" from the center of the upper drivers side bellhousing bolt. This is my CJ's T176 bellhousing, I used the Hesco pilot bushing to mate the 4.0 crank with the T176 input shaft. I used the CenterForce II clutch off my 258. With the 4.0 flywheel you have to run the 4.0 starter.

 

I used 1/8" steel to make the CPS adapter. Those are 258 manifold washers for spacers. I was off slightly with the 1" holesaw so I used a die grinder and opend it up to where I needed it to be.



Then I cut a piece of roofing rubber for a gasket/seal. Drilled and tapped some 8-32 holes and used stainless screws to secure the seal. Ismeared some black silicone between the rubber and bellhousing.

 

I ended up using an XJ power steering pump. The XJ has a reservoir built into it whereas the YJ has a remote reservoir. I have broken the reservoir on my wifes YJ so I went with the XJ pump/reservoir on my swap.
With the XJ pump/reservoir I couldn't use a YJ airbox. So I bought a '97 TJ 4.0 airbox and tube on Flea-Bay(I think the 2.5 set-up is the same). I used some 1/8" x 1" flat stock to bend up some mounting brackets for the airbox, while I was at it I used the same size flat stock to mount the PDC to my CJ battery tray(I'll have to change this when I get to mounting my Painless dual battery wiring harness). To connect the CCV system to the YJ EVAP canister(you can use the XJ canister) I used the main tube from the XJ and bought some CPVC fittings at the Rutland, Vt Tractor Supply and made up a manifold and bought some hose at NAPA...auuughhhh...turns out they have the pieces on the "HELP" rack so I could have used those rather than the Tractor Supply stuff....anyhow it's all connected....
To mount the CJ motor mounts on the 4.0 block I had to drill one hole larger and get a fine thread metric bolt...I mention this because this 12mm fine thread bolt is a HARD to find item!! I cut the XJ head pipe and got some flex pipe from NAPA to connect it to my exhaust until I can get a new pipe bent up. I don't like how close the XJ pipe is to the oil pan/bell housing.

 

Rather than mount the fuel pump in the tank I mounted the NAPA P74155 fuel pump on the frame cross member. I ran new fuel line from the tank to a universal 5/16" NAPA #3002 fuel filter then stepped up to the fuel pump.Out of the fuel pump I used the 5/16" NAPA high pressure rated fuel line and stepped it up to 3/8" going into a NAPA high pressure fuel filter #FIL3486 (standard replacement for a '93 YJ) using the XJ fuel filter bracket. From there I connected to the CJ's steel fuel line to the engine bay. I bent some 5/16" steel line around the front of the frame to the drivers side and used the high pressure hose to connect to the 4.0's fuel line. I also used NAPA 1/4" high pressure hose for the return line, I don't think I really needed high pressure hose on the return side but better safe than sorry for the small investment. I connected the return line to the CJ's steel 1/4" return line. While I'm thinking of it I used a YJ throttle cable.

 

I'll try to get a picture of the fuel pump/filter setup to post. Over all it was an easy swap. I spent a LOT of time researching this info on the net. The stuff I mentioned above came from several different sources that I found on the internet with maybe the exception of the CCV plumbing. Of course you'll have to adapt things to work on your CJ. I don't think I mentioned the MAP sensor, it simply mounts on the firewall. Overall I am very pleased with my 4.0 swap!

 

WOW, that's some great feedback.
KMAN, you could publish a how-to book with that information. Thank you.
Well it looks like I have a new project. I'll update this thread when I get started on the swap.
Please keep the ideas coming.

 

Heres the 4.0 in the CJ's engine bay. You can see the computer mounted on the drivers side fender - I am thinking about moving it inside under the dash. Thats the MAP sensor on the firewall above the rear of the valve cover. The TJ aibox and tube also stand out. The 2/0 cables zip tied are for powereing the Cole-Hersey solenoid for the rear mount winch.

 

Some pics of the CCV plumbing

 

Heres a shot of the pre pump fuel filter and the fuel pump. I used a clamp for chain link fence to mount the pump. I put a wrap of roofing rubber around the pump. I drilled a hole in the frame rail and tapped it 1/4-20. Then I screwed in a 1/4-20 stainless bolt from behind and lock-tited it. The clamp slides over the bolt then I used a stainless washer and nut. Thats a ground wire attached to it. I know it would have looked better if I washed it but I'm getting ready to leave tommorrow, gotta teach a class in St.Croix next week.

 

Heres the high pressure fuel filter mounted on the passenger frame rail.

 

A stock 2 piece 4.0 pilot bearing on the left and the Hesco on the right. When I bought the Hesco bushing last January I paid around $40. for it...I see they now have it listed for $114. As I recall Novak also has one available.

 

Great posts Kman!

Just for everyones info, there is a forum dedicated to swapping the 4.0L into CJs http://www.cjoffroad.com/forums/forum.asp?FORUM_ID=24

XJs are very popular here, and wrecked, rusted or worn out Cherokees seem to be quite plentiful. I think you'd do well to get the entire vehicle if you want to do this swap.