1999 ZJ motor into 1999 XJ

Well despite the claim contrary by the seller, the motor I recently bought is a ZJ 4.0 from a 1999. I guess I learned something about the markings on the motor. It was sold to me as a complete XJ motor.

Most of what I have read searching here and elsewhere on the internet indicates that the solution is to switch all the component parts from the XJ motor (waterpump, exhaust/intake manifold, engine mounts, etc) on to the ZJ block. It seems however that 1999 was a year of transition for the ZJ but not the XJ. Do I have that right? Are these blocks compatible?

Is there anything else I need to be concerned with on this ZJ block? Trying to decide if I need to return the motor? It came with a 30 day return policy which I still have. Though the parts are now stripped off.

Any idea or suggestions would be appreciated.

The ZJ production years were from 93-98 so if you infact did indeed get the motor from a 99 grandcherokee then it would be a WJ which there is a very big difference in the two vehicles as they share nothing but the inline 6 and the name but nearly everything else was changed. The motor may or may not work in your Jeep. I am unsure if the 99 Grand Cherokee is distributorless or not so check for a distributor if it has one then you should be good to go. You will definitely need to swap over the accesories and their brackets from the XJ motor but the water pump may be the same even if they are visually the same, depending on the route of the serpentine belt if may be reverse of the XJ pump would be bad news if you tried to run it with the XJ routing. Research and part number comparison will help you there. Good Luck

Yes, it has the distributor system like in my '99 XJ. Is that the biggest tell for compatibility? There is also a sticker on the valve cover that has the letters 'ZJ'. The corresponding sticker on the motor in my Cherokee has 'XJ' in the same spot. There is a date code, but I can't figure it out. Maybe it is a Julian date.

XJFang said:

Yes, it has the distributor system like in my '99 XJ. Is that the biggest tell for compatibility? There is also a sticker on the valve cover that has the letters 'ZJ'. The corresponding sticker on the motor in my Cherokee has 'XJ' in the same spot. There is a date code, but I can't figure it out. Maybe it is a Julian date.

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That means one of 2 things....(1) the engie you bought is a '98 or older or (2) someone swapped a ZJ valve cover onto a WJ engine.

Cottontail said:

(2) someone swapped a ZJ valve cover onto a WJ engine.

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Were they compatible?

So far from what I know on the junk-yard motor is that it has different engine mounts, and different manifolds. I'd think that precludes it certainly as having come from a XJ.

A ZJ block is compatible, a WJ is not.

What is the Chrysler part number cast into the side of the block (near the motor mount) and the date code near the rear frost plug ?

.

Part number (as read over the phone to me) 53010341

Number by the freeze/frost plugs 32197

I'm thinking this is a '97 motor.

According to this - http://www.pera.org/articles/eb40319.htm - it is a 97-98 XJ/ZJ/TJ block.

if in fact you do determine that it is a (i was told late 98 zj got the clean sheet design)wj block, brown dog offroad can make you brackets that will drop it into a xj/mj. the kit is S2883, its a custom kit and not on the website. you can even call them up and have them run your block number, they were very helpful when i ran into this problem with my mj.

I bought the XJ mounts from Brown Dog. I'll know more tomorrow.

Here is my status: The yard is exchanging the motor. Delivering it too.

Thank you to those that responded, bring my Jeep education up some more.

was it the clean sheet block?