89 to 92 4.0 engine swap.

[jstlink]

blew my 89 4.0 xj motor.have a lead on a 92 4.0 to go back in the 89 xj.will this switch work?not sure what the major differences in the motors were from those years.

 

[boise49ers]

A Lot

It isn't as easy as you would think. You would have to change your wiring harness because the 92 is the first year of the HO engine, Also the down pipe on the exhaust is different. The Cooling system is an open system as opposed to the closed system. The wiring is probably the biggest and most expensive.

 

[Bouncy]

Um...yeah. Skip most of that last post info...Its true but not needed.

I put a 95 motor (same as 92) in my 90 XJ (same as your 89)

Differenences are listed above. HO head, cooling, electronics etc.

Here is the swap in a nutshell.

Your intake will bolt up without any problems. Switch to the 92 or later exhaust manifold..Or buy an APN header for $119...Search naxja for the link. Its cheap and good.

Your cooling will work..Or you can switch to open cooling system. Either works fine.

As long as you pay attention as you switch motors...All sensors will move over just fine. Cooling moves over too. You have to switch the distributor and oil sending unit...Again all sensors need to be moved over.

You'll have a little fun putting the vacuum lines back into the top of the valve cover but otherwise, they work fine too.

Make damn sure you don't damange your Crank Position Sensor and reuse your old flex plate as it has the proper triggers for your crank position sensor.

Otherwise, Its BOLT UP without any big problems.

All accessories still bolt up the same...as long as you don't change intakes. The long blocks are identical from valve cover to oil pan...Just the HO head difference and it bolts up no problem at all.

If you have more questions, PM me as I did this swap last summer and getting ready in a couple of weeks to put a stroker motor in as well.

 

[Bouncy]

Forgot to say I guess...You do NOT need to swap any electrical or computers...Just move old sensors to new motor and it runs the same. 4.0 is a 4.0 is a 4.0. Some just flow a little better with the HO head.

 

[Cam]

Forgot to say I guess...You do NOT need to swap any electrical or computers...Just move old sensors to new motor and it runs the same. 4.0 is a 4.0 is a 4.0. Some just flow a little better with the HO head.

What about the other way around? Trying to put a 89 4.0 into a 92 xj?

 

[75SV1]

What about the other way around? Trying to put a 89 4.0 into a 92 xj?

Could just swap on the HO head on the RENIX block. Also, watch CARB mandates. OK to swap later engines in older vehicles, not the reverse. Yeah, most States won't check. Probably even those that Do.

Also, I think HESCO sell a wiring adapter to swap a RENIX to a HO Throttle Body.

17 – HO engine into Renix

CRUISER'S MOSTLY RENIX TIPS HO INTO RENIX SWAP This swap is easier than some will lead you to believe. And generally Pooh-poohed by those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it ...

comancheclub.com

Only skimmed it. I did put on a '95 HO Valve Cover on my RENIX. Also, a 93-95 ZJ Valve cover would be better. I did the Late Style Big Tube CCV Tube on mine. I had to splice in some tubing. Might not be a problem with an HO Intake.

 

[Cam]

Could just swap on the HO head on the RENIX block. Also, watch CARB mandates. OK to swap later engines in older vehicles, not the reverse. Yeah, most States won't check. Probably even those that Do.

Also, I think HESCO sell a wiring adapter to swap a RENIX to a HO Throttle Body.

17 – HO engine into Renix

CRUISER'S MOSTLY RENIX TIPS HO INTO RENIX SWAP This swap is easier than some will lead you to believe. And generally Pooh-poohed by those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it ...

comancheclub.com

Only skimmed it. I did put on a '95 HO Valve Cover on my RENIX. Also, a 93-95 ZJ Valve cover would be better. I did the Late Style Big Tube CCV Tube on mine. I had to splice in some tubing. Might not be a problem with an HO Intake.

I appreciate it! What I have going on is I bought a 92 xj from a guy that couldn’t get it running after swapping an 89 renix 4.0 into it. Renix block, all HO top and and accessories. It will crank but no start. The IAC and TPS are new, HO dizzy is indexed and engine is at TDC. CPS is reading about 3400 ohms(I’m not sure if that’s good or bad).

A lot of info but I’m at a loss

 

[75SV1]

Not sure on the CPS, either. I'm sure others will step in. I've had two XJs that would turn over, but would not start. On the '98, it was a bad coil. There is also a 'CPS' in the dizzy. Its a flat plastic disc. It should throw a code though.
On my 2000, it was the key switch. I was checking the injector relay or firing with a NOID light. You can rent one from one of the Part Stores. It only flashed as I released the key. A friend told me to try and replace the electric board for the ignition key. It worked for me. Spark plugs? Wires? Also, fuel pressure? Volts at fuel pump?

Edit: Also, if it backfires and doesn't start, then your Dizzy might be 180 degrees out. I did have it out 180 on my 2000. It ran, but not a lot of power. Sort of a different beast with waste spark though.

 

[mewz99]

Renix block, all HO top and accessories. It will crank but no start.

That sounds to me like it's got the HO flex plate installed, which won't trigger the Renix CPS properly. [Edit: errrr...vice versa - Renix flex plate which won't trigger the HO CPS properly. Same problem, just opposite] You also won't see the tach wobble at all while cranking.