93xj Engine swap into a 89mj ? ??

[rsquirt83]

I have a complete running 1993xj (4.0HO Auto/231tc) And I'd like to pull everything and move it over to my 1989 MJ (4.0renix auto/231). I already plan on using the computer from the 93 in the swap. Using the 93 wiring how much of this will be straight forward?

 

The MJ already has a fuel cell with remote fuel pump and filter. I'll be making the switch from my column shifter to a floor shift. The truck already has buckets with a center console.

 

I plan on pulling the engine trans/tc (starter, computer, EFI, wire harness..everything) out in one unit and moving it all to the Comanche.

 

What do I have ahead of me?

 

-Richard

[BLHTAZ]

Just wanted to say welcome to the Club :cheers: .

There are a couple of the guys around here that have done this and will have a lot of good info for you on it. I know the basics, but have never actually done the job so we'll wait for the ones with the actual experience here. ;)

[rsquirt83]

Thanks !! :waving:

 

Long time reader first time poster, well second now. I've gotten alot of great info from here and naxja.com but I just never have anything worthwhile to add.

Sites like this make me proud to own a Comanche.

[JeepcoMJ]

the mechanicals are easy.

 

the engine bay wiring is easy. you will need to remove the front clip from the MJ to do this so you can remove the wiring...but you don't need to remove it from the xj since the wiring doesn't go through there.

 

you need to swap the dash harness, and splice the wiring together in the kick panel to the fuel pump, tail lights, and interior lighting. this isn't too fun.

 

I just cut the rear harnesses from the xj AFTER the xj's rear connectors, and then cut the dash harness from the MJ BEFORE the MJ's rear connectors, then used that as a crossover harness since the connectors used aren't the same.

 

but I'm still not done with the wiring so I can't say much else. the tail light wiring is simple, and you'll have to add an extra wire to the xj dash harness going to the brake light wire in the driver's side kick panel, so that your brake lights work. this wire gets put into an open pin on the turn signal connector on the steering column.