Hello my names Sean. I just purchased a 94 4.0 HO. I drive a 89 wondering what all goes into the swap. Like does the harness have to be changed? Or any thing else. Thanks.

 

Howdy Sean. You are in one of the right places. I could "copy/paste" it but you may as well click on my sig. Right on-top is "Cruisers Tips". There is in there the HO to Renix swap. Cruiser, myself and others will be here to help out. Welcome to CF!

It's pretty important you fill out your info so on post #56 someone does not need to find post #1 to see what you have.

 

Not sure what you mean? How to find the post

 

Treat the 91 like a long block, Keep the flywheel/torque plate with the pre 91 Renix ECU. (that would be the one from your 89). The 91 on PCM uses allot of different sensors, including the CPS that goes with the flywheel/torque plate from post 90 Jeeps. Welcome!

 

So use the manifolds from the 89?

 

In my signature it says 87-90 Jeep info, here> Maybe what you are using doesn't show it?

 

Here ya go. Easy as pie.

Cruiser’s HO into Renix Swap

This swap is easier than some will lead you to believe, generally 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 as swapping in a long block.

The HO and Renix have some differences but none that can’t be overcome very easily.

Any HO engine from an XJ or ZJ through 1999 can be used. One running change was that the rear of the head was no longer drilled and tapped for the temperature gauge sender beginning in the 96 model year. The sender can be relocated to the threaded hole in the thermostat housing taken from the HO engine. You’ll have to extend the wire to that location. Some brave souls even drill and tap the HO head for the sender.

You will be using the intake and exhaust manifolds from your Renix, along with all your sensors and wiring. Since the intake ports of the HO are slightly different, you use the Renix gasket. Exhaust ports are identical.
You will need to use your Renix distributor as it is different than the HO because they use different fuel management systems. The flywheel or flexplate from the Renix must be used so your CPS gets the correct signals. The valve cover from the Renix allows you to keep your CCV system intact and requires no modifications.

The HO block will have a plug in the coolant galley on the driver’s side of the block, closest to the front, which needs to be removed so your Coolant Temp Sensor can be installed in it’s place just as it is on the Renix. It requires a 5/16” square drive or a modified 3/8” drive that has been ground down to fit. Do this before installing the engine.

As for the knock sensor, which is located just above the oil pan on the driver’s side of the engine about mid way, all the blocks I’ve seen are threaded for it. If not, I’ve heard they may be drilled but not tapped. Tap the hole if that’s the case.


Revised 03/28/13

 

Thank you so much this information is just what I needed. Such a major help. Thank you. And what do I do about cam and crank sensors.
?

 

Use your distributor. Use your CPS.

 

Not sure I know what cps means?

 

Crank Position Sensor

 

You copy and paste like a seasoned master.

 

How'd that happen? A 60 year old computer illiterate dip**** as myself. It's a miracle! LOL.