92HO in 89 XJ

So after 256K miles my 4.0 has finally died. I figure since I have to replace it why not put a newer 4.0 HO in so I can have the addded HP and Torque. I am wondering if anyone has done this and any idea of the difficulty involved. I figure I will just get the complete engine, wiring loom, and ECU from the donor vehicle and then pray to the gods of 4x4dom that it works. I am planning on using a 92 or 93 in hopes that things didn't change to much and it will be simpler. Any input, suggestions, or engine donations, and the related would be appreciated.

Thanks

I thoughts of doing the same to my 87. I was just thinking about using the block and head. Is there difference between an 87-90 and 91+ block and head besides the temp sending unit by #6? Would all the accesories and manifolds fit?

8700XJS

Heck, my 84 has an 92 4.0 H.O so I dont see why you folks couldnt do it.

P.S. I bought her that way so I dont know all the ins and outs about installing one tho

I thought you couldn't fit the 4.0 in a pre 88. They must have moved the firewall.

Atl XJ said:

I thought you couldn't fit the 4.0 in a pre 88. They must have moved the firewall.

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My 87 Currently has a stock 4.0 in it.

87 is the first year for the 4.0 242.

8700XJS

thats what I meant :dunce:

I put a 98 in my 89. It wasn't too bad, with a couple manuals. With everything out off the 92 it shouldn't be that bad. It took me probably 2-3 weekends. The wiring was the only problem that i really ran into. mating the 2 harnesses and getting everything to work probably took the most time and thinking. the fuel system is differnt so you can either swap the tank to the new one or make a custom fuel system. i went with the fuel system and probably spent more than the other tank would have been cheaper. there's a couple things i probably would have done different. if you have any questions feel free to email me.

Donovan

BMWSOB said:

The wiring was the only problem that i really ran into. mating the 2 harnesses and getting everything to work probably took the most time and thinking. the fuel system is differnt so you can either swap the tank to the new one or make a custom fuel system. i went with the fuel system and probably spent more than the other tank would have been cheaper. there's a couple things i probably would have done different. if you have any questions feel free to email me.

Donovan

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If I plan on just using the block and head will my intake manifold work? I would probably pony up for a new exhaust. Also will the injectors and rail work? Will a distributor work or will I have to go will direct ignition? If I get one that new. Finally what is different about the fuel tank?

I would really like to do this because my cherokee is in good shape as far as the body and drive line go. I have the AW4 trans with a 242T-Case and D44 rear end. My motor is a little tired.

8700XJS

I'm haven't actually done just the block and head swap. But i'm pretty sure you can swap everything over to the new short block. I know the distributor will work on that engine. The fuel system should work as long as you use all your current stuff. The difference in the fuel tank is how the pressure is regulated. The newer system is a returnless rail that is regulated in the tank. It uses a different pick up and that pick up goes with the new tank. so its kind of a domino effect. As long as you use your renix fuel system and computer i don't think you should have any problems.

Thats the same reason i put a new engine in mine. I ended up blowing the 242 and i couldn't get the older trans to work with the new trans computer. I didn't feel like doing all the electrical work to make the old trans computer work independently just to have that trans blow up so i replaced it with a newer trans and transfer. I still love the cherokee.

Donovan

Sooo it would have 2 b an engine/computer/transmission/fuel system swap?
I happened 2 b looking at this with my 89 and a 93 grand.Only i have 2 do it quickly, as n a week.

It doesn't have to be but it makes it really simple. Just put it all in there... Doing just parts of a swap makes in more complicated as in which exact parts you want new and what needs to be new with that and such.

If you have everthing to do the swap it can me done in a week easily.

Donovan