86 4.0 Engine swap

[Patrick_Rash]

With a build date of  8/1/85, is the firewall far back enough to do a I6 conversion pretty easily?

[omega_rugal]

we don't know, you tell us... some pics?

[Pete M]

I seriously doubt it, but if you can snap a pic of the firewall at the back of the engine we should be able to tell you.  

 

also, it doesn't really matter one way or the other since the fix is just a couple whacks with a big hammer.   

[AMC86Kid]

It will fit 

as far as how easy it is 

that’s all gonna depend on how good of a mechanic you are 

[JimB]

My 1986 came with a 4cyl. I had to knock where the firewall curves into the transmission tunnel, about where the temp sensor is located at the back of the head. In about an inch or two.

Also the support for holding the radiator needs to be swapped. I had a 1987 XJ that I used for parts and comparison. 

[omega_rugal]

On 7/4/2020 at 7:49 PM, JimB said:

Also the support for holding the radiator needs to be swapped. I had a 1987 XJ that I used for parts and comparison. 

 

why not keep the radiator? you think it may not be adecuate? from what y have seen it´s a lot of modding to fit the large 4.0 one

[JimB]

I know that the fan on the 4.0 sits off to the passenger side. Not directly in the middle. I had a 1987 cherokee for parts. So I decided to drill out the spot welds and reweld new parts. 

You might be able to use an electric fan and do away with the mechanical fan all together. I also put the auto trans from the 87 into the 86. I had to have the driveshaft shortened.

Other than that it was not that big of a job.