Just confirming this will work


New Member
Jun 13, 2023
North East Pa
Here us the story.....
HAD a '89 YJ. ( last summer," my retirement project").
Got a rebuild able '86 4.2 to drop in it, but, never got the chance.
Got an ," WOW I can' t refuse this offer" to sell YJ.
Was 1/2through rebuild on '86 engine at the time.
TRIED to sell as a package deal,but, guy didn't want motor.
So, now I got a " fresh rebuild 4.2" and nothing to drop it in!!
Going Saturday to look at a supposedly " clean, rust free" '04 Wrangler, 4.0 auto, ( 4.2 came outta a manual trans CJ)
Now, before we all FREAK, I want to drop this 4.2 in, go carburetor, ( I got complete engine from donor CJ, intake, exhaust), drop in a HEI dist., unplug, remove all the injection. ( I'm ol school, like simple easy to set up, maintain kinda guy). I CAN work on ," modern" computerized machines, but, prefer carbs!
I' m pretty sure it will bolt up, some coolant hose mods, figure out fuel tank sending unit to remove electric fuel pump,, ( heater hoses, carb linkage).
Will this bolt up, fly wheel, most likely harmonic balancer all fit the 4.2?
I would hate to have fresh motor, a nice project, that neither will fit!
Just trying to ," make sure", before I jump!
Does the 04 have an electronic controlled transmission? If so, you're potentially opening a real can of worms.

Also, this would probably get more traction on the TJ side of the Forum
If the trans won’t work you can always go to a turbo 350 and various others. Novak transmission is a great place to find knowledge and this type of adapter. I completely understand the oldschool approach. I’m leaving my 89 a 4.2 and all electronics are gone. Clifford intake and Holley 390 cfm 4 barrel. It’s my retirement project also.