YJ 4.2 on a cj frame?

[CJDan]

Yet another thread started by me, sorry! Have many questions.

I have a 4.2 from a YJ I am going to use for my cj. The problem is the motor mounts are different. The bolt patter on the YJ is 2 up and 1 down...for the cj block it is 2 down and 1 up. I read that I have to fabricate the YJ frame to fit YJ mounts, how would I go about doing that? Is there any threads on here that did that?

 

[69jeepcj]

are you talking about the actual engine mounts that bolt to the block or where it bolts to the frame horns coming off the frame?? you can buy or fabricate your own mounts.

 

[eric m]

Maybe I'm missing something but why don't you source some cj 4.2 mounts and use them with your current engine? For what it's worth my dad has a 90 yj with the 4.2 that a previous owner rebuilt using a cj block.

 

[superj]

yup, just get the right motor mounts.

i helped a buddy put a yj 4.2 and yj transmission into his cj7 and all we had to do was use the cj transfer case

 

[CJDan]

Where it actually mounts to the block. The bolt patter on the YJ 4.2 is 2 on the bottom and one on the top. The CJ has 2 on the top and 1 on the bottom(I believe) . So if I buy the Cj engine mounts that go to the block, it will be upside down.

 

[CJDan]

Wow you are all right. I was totally wrong. Completely screwed that one up...happy I don't have to spend money now!

 

[superj]

you can interchange a fair number of parts between the early yj and the cj. even body parts and tops. the main issues will be the t-case and front axle since the cj has the diff on the passenger side and the yj has it on the driver's side at the front. other then that, you can swap tubs, fenders, grill, hood, windshield frame, windshield, roll cage, seats, dash, steering wheel and column, engine, trans and rear seat. you can use the axles but the yj has a different bolt pattern then the cj so you would have to swap both and if you do that, then you need the t-case as well or no 4x4. the bumpers can be swapped also. some of the parts will require drilling the holes over a bit or adding a little spacer and some require the use of other matching model parts or they won;t line up.

but you can swap tons of stuff between the two models