Motor Swap - 2004 4.0L in 1993 XJ?

Broken Rod... Motor Swap Q's - 2001 4.0L in 1993 XJ?

I was taking a nice leisurely drive in our 1993 XJ to the hardware store on Saturday when I heard and felt a small explosion that was followed by lots of oil smoke. I knew what had happened before I even crawled underneath to look. I pulled the oil pan today and found pieces of a piston. The block has a 2" diameter hole in the side of it. The current 4.0L HO motor is toast! Time for a "new" one.

I would like to find a lower mileage mile motor and drop it in. That has forced me to look at newer 4.0L's from wrecks, junk yards, etc. It looks like I can buy a lower mileage motor for a reasonable price. My concern is whether or not the 4.0L from say a 2001 XJ will drop in without major effort into my 1993. I've tried a few searches and I've learned all about the difference between WJ and XJ water pumps, motor mount styles, alternator locations, improved intake manifold flow, distributor vs. distributorless, OBD-I vs. OBD-II etc.

What I can't seem to verify is if a 2001 (or similar) 4.0L will drop in to a 1993 originally equipped with a 1993 4.0L. I guess another way of asking would be... can a 2001 4.0L long block from an XJ drop into a 1993 XJ? Ideally I would keep my existing wiring, intake manifold, throttle body, all of the sensors, and reuse them on the new motor. I've read that converting the electronics can be a bear. Different fuel pumps, speed sensor in the transfer case, etc. At this point I just want to get the rig back on the road ASAP. I am not looking for the combination that provides the most performance.

This has probably been covered but I couldn't find any links during my searches. I tried all sorts of different keywords without much luck. If there's a thread that has this information please flame me if necessary and then provide the link :thumbup:

Thanks!

Aloha

Do you mean a 4.0L from an 04 WJ? They stop making XJ's in 01.

There were no XJ's in 2004 so the 4.0L would be coming from that year would be out of a TJ/WJ or WJ. There are significant differences between '04 4.0L in a TJ and XJ when compared to your '93 XJ 4.0L block. A few that I can think of off the top of my head are the engine mounting brackets, the water pump, and certain accessory mounting points (which you know of).

It is still possible to swap an '04 TJ/WJ block in, but it will require a little bit of 'extra' effort. It's not going to be a plug and play operation.

Here is a neat link for the 4.0L engine and some of the differences between years: http://www.enginebuildermag.com/Art...its_time_to_say_goodbye_to_an_old_friend.aspx

Fat fingers... 2004 = 2001. The numbers row on my keyboard doesn't work so I use the calculator buttons on the right. Let me edit it.

alohajeff said:

Fat fingers... 2004 = 2001. The numbers row on my keyboard doesn't work so I use the calculator buttons on the right. Let me edit it.

Click to expand...

Ah, ok - that's more like it. Yes, the '01 XJ longblock should work in a '93, but if you're looking to put the newest XJ 4.0L in yours, might I suggest going with a '99 4.0L longblock with the 0630 head casting.

Just do a search for 0331 cylinder head on this forum and you'll see why you want to avoid that. Long story short - it's very prone to cracking at any time. The 0331 cylinder heads can be found on the '00 and '01 XJ 4.0L.

Can I swap the existing, albeit tired but functional, head from the 1993 block over to a newer block?

I visited that site... fun facts regarding the variations. Sounds like the actual block itself has seen a number of revisions. What I'm worried about are the mounts, the accessories and required brackets, and any difference in machining on a distributor vs. distributorless block.

Aloha

Yes, you should be able to swap the older head over, but I'd really recommend getting a valve job on it while you've got it off. There shouldn't be any differences for the distributor vs. distributorless block. The hole for the distributor is still there on the '01 block, but it is filled with a cam position sensor instead. If you keep the '01 cylinder head, you'll have three (maybe four) mounting points for the coil pack which you just won't use.

I think the motor mount brackets from your '93 will bolt up to the '01, but I'm really waiting on someone else to chime in with a more definite answer to that.

From the sounds of it, you already have or have a lead on an '01 XJ longblock? Otherwise, I'd really implore you to look at a '99. It'll also be less money if you go to a junkyard to get it since they'll often just look at the year to figure out a price.

You can swap the 93 head on to the 01 block, its recommended that or 03+ head. You exhaust manifold may or may not work with the head. The exhaust ports are higher on the 01 head, but the 93 exhaust may work.

Thanks guys. I've been hesitant to pull the trigger on a motor purchase fearing a newer block will create more headaches than it solves. It sounds like with a little bit of swapping I can basically take what I've got and transfer it over to a 2001 (or similar) model year block and make it work. That's good news.

Thanks again!

Jeff

Engine block bolt patterns are identical. Thus, the engine brackets and motor mounts are the same.

I picked up a 1998 engine up from a member for $350 and started the R&R today. I noticed a few differences but nothing that I can't handle. Like you said Brown Dog, the block is the same. I'll be swapping a few parts from old to new to make it all work and will keep my fingers crossed that when I turn the key she runs. I'm ordering some reman'd injectors to use in the 1993 fuel rail and a new oil pump. That's about the extent of the "upgrades" to the 1998. I'll post a wrap-up when the swap is finished.

alohajeff said:

I picked up a 1998 engine up from a member for $350 and started the R&R today. I noticed a few differences but nothing that I can't handle. Like you said Brown Dog, the block is the same. I'll be swapping a few parts from old to new to make it all work and will keep my fingers crossed that when I turn the key she runs. I'm ordering some reman'd injectors to use in the 1993 fuel rail and a new oil pump. That's about the extent of the "upgrades" to the 1998. I'll post a wrap-up when the swap is finished.

Click to expand...

I hope she fires right up too considering that's my old engine! Let me know how it goes.

Don't forget to change your motor mounts while you've got it out.

The mounts from the 1998 are good... the cheapo replacements I bought for the 1993 last year are in worse shape. Go figure.

Today I swapped the throttle body sensors from the 1993 throttle body to the 1998. I also transfered the new-ish water pump from the 1993 to the 1998. I decided to pull the 1998's thermostat housing off and was surprised to see somebody had installed a 160* thermostat. I put my 180* in and put it back together using a new gasket. With nothing better to do I then pulled the oil pan, oil pump, and then removed the oil pump cover to take a look at the gears. The gears have some discoloration so I went ahead and splurged $24.99+ tax for a Melling K81A pump rebuild kit. I cleaned all of the crud out of the pickup screen and found nothing out of the ordinary. To be safe I pulled the oil filter adapter off and was glad I did... somebody had silicone'd the adapter to the block. I put new o-rings on the adapter and the bolt. I found three good size cracks in the 1998 exhaust manifold that I'll weld up tomorrow. Hope to get the motor in on Monday.

Aloha

THANKS SooperGoober!

The engine is in and runs. All in all it wasn't too bad. I had to drill and tap the 1998 head to use the water temp sender from the 1993. I broke the old temp sending unit taking it out and had to replace it. I swapped the newer 1998 power steering pump bracket and belt tensioner and that required drilling out the 1993 pump mounting holes. The tensioner upgrade required a 1998 serpentine belt which is 95" inches instead of the 1993's 97.5". I replaced the majority of the vacuum lines and put hose clamps on the lines going from the air box to prevent dirt from getting sucked in again. I splurged on a set of Ford reman'd and matched injectors. New motor mounts. Welded the exhaust manifold and ordered a new Walker down pipe from Amazon ($39.xx delivered) to replace the smashed one that is on there now. I'd post a picture but it looks just like the last motor did... except for one important difference... there's no fist sized hole in the driverside of the block!

I've also ordered some new 4 awg wires to better support winch use. The existing ground and positive wires are pretty nasty and have to go.