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MJ ? in XJ modified section


NAXJA Forum User
Sorry got no response in MJ section. Found a 1986 Comanche with 4.2, AX15, and NP231. Obviously not stock, just want to know if there any known issues with early MJ/XJ bodies with this combo. It's running a carb and he has 4.0 head for it. Was going to look at it if I have time.
Depends on what you want, and the budget.

I would swap on a 1997-2000 front clip, doors, interior, and OBD-II engine controls.
The 84-86 would have been an I-4 or a 2.8l V6 from the factory, and some comment that the firewall changed in 87 for the longer I-6 and forward.

If it's already got a 4.2L, then that complication has already been customized.

I'd be more concerned about how they got the 4.2 in there and what hack happened to the wiring harness. If you're up for the project, they are cool trucks. Otherwise I think they are similar to all other MJ trucks.
From Novak:

With the change to the 4.0 engine, the engine bay of the Stage II Jeep XJ was changed in 1987, including small changes to the firewall, inner fenders and most significantly the front clip. This is one of the key facts that individuals who don't care for large levels of pain and expense should consider, and not make the mechanically dangerous assumption that a 4.0L should swap into a Stage I Cherokee. We at Novak have fielded many a sad call from people who have tried it hoping for a much easier conversion, further supporting one of our leading maxims, that "Jeep parts are often the hardest parts to swap into Jeeps."

As XJ ranger points out, somebody has managed to get an inline 6 into that engine bay which was originally configured for a V-6. You will need to asses the situation and determine if that change was made in a graceful manner or if it was a hack job. If they swapped out the old front clip and converted to the new front clip, and did it well, then the odds are in your favor. If, on the other hand, it is all scraps of angle iron and bailing wire, run away fast. Most likely it will be somewhere between the two and you will have to decide if it is worth your efforts.
Going from memory and readings on the net, they either had to put in a 'new' firewall or dent it in. So, look at the rear of the engine near the firewall.
I haven't checked it out yet. Hopefully Friday if I can arrange something. Spent last 3 days tearing out our master bath for a complete remodel. Oh what fun!