Rebuilding an XJ 4.0--in Hemi Orange!

[BuckeyeBullet]

Hello everyone! I bought my first Jeep, a 2001 XJ, 6 months ago as a non-runner with 216k on it. It was driven with no coolant until it quit running. Then it sat in a field for a year until the owner's wife said it has to go. I'm bringing it back as a dual-purpose ride. Mud is fun but my focus is exploring the backcountry of northern Utah and nearby states off-pavement. My daily 300mi per week transport is a KLR650E but in snow and really cold weather it will be nice to have the 4x4 and piece of mind of a Jeep. My pickup is 2wd and a little too big for off-road adventures although I've definitely taken it places I probably shouldn't have ;-)

My plans are to give the Jeep a 2.5 or 3" lift, shallower backspaced wheels for a wider stance, flat fender flares, a fiberglass type RTT, and custom bumpers set up for a trailer-hitch mounted removable winch (fabbed by me). There will be some fender cutting. I can't get anywhere without a running engine though so I'm starting this build thread with the engine. It is the original 4.0 punched .030" over. I am using a Crane performance camshaft for an AMC 258 which should give much better torque and a little better power, and I've got a Clearwater head on it so it hopefully won't crack like the factory heads do. The nearly-finished engine went into the Jeep today but I will post some photos from the beginning, maybe a couple photos a day until I get caught up to where I am now. Questions and comments welcome!

Bringing her home:



Beginning the teardown--head gasket breached across the middle 4 cylinders:



Here is one of the burnt pistons. The red arrows show where the piston was rubbing the bore. The compression rings are seized on this one:

 

[BuckeyeBullet]

The teardown continued and I took the block to a shop in Logan, UT to be bored .030", decked, and have the crankshaft polished. When it came back to my shop a month later I began to put it together. I used Sealed Power coated cast pistons on the stock rods. This won't be a serious performance engine, I just wanted it to be strong and reliable. The block heater I added is a Mopar part, installed in the front core plug hole where the factory would have put it. I was a little concerned with uneven heating but there really is no other place to run the wiring to the block heater with the exhaust manifold in the way.

 

[jeepdreamer]

Mmmm... fresh engine. YUMMY!

 

[BuckeyeBullet]

I've of course got tons more photos of this build than I'm posting here, so if anyone has specific questions about some part on their 4.0, chances are I've got a photo of it. Here we have the new cylinder head from Clearwater Cylinder Heads. Straight-forward company to deal with. My engine, being in a 2001 Jeep, has the notorious 0331 cylinder head. It flows decent but is very prone to cracking between the #3 and 4 cylinders. Mine wasn't visibly cracked but it had been overheated badly and the evidence pointed to a warped head. I didn't bother to check it, for the price the Clearwater head was only a little more than rebuilding the old one and it offered a better design. The Clearwater head is a cheaper alternative to the Alabama head. Both have beefed-up material in problem areas and should be a lot more durable than the stock head. We'll see...although I don't intend to run without coolant for extended periods like the previous owner did. The timing chain is unfortunately not a roller chain like I wanted but since I'm using a cam for a 258ci AMC engine (the 4.0 is based on that motor) I had to use a special gear set which is only offered for the stock-type plate chain.



Since I like my Mopars, and Jeep has been a part of that family for a while, I decided to go with Hemi Orange paint instead of the boring black. There will be plenty of wiring and hoses and stuff obscuring the engine once it's fully installed but hey, it needed paint either way and it'll stand out a little better like this. I just wish the machine shop had actually cleaned the block better like I asked them to, would have saved me some prep time.



This is the exhaust setup I'm going with: Gale Banks Torque Tube header and factory Y-pipe. I had ordered a Rugged Ridge header which is the same design only $140 cheaper, but of course they were indefinitely out of stock. The Banks unit has a lifetime warranty, not sure if the Rugged Ridge does. I liked the 1/2" thick flanges and 409 stainless of these pipes, plus they are an attempt at being closer to equal-length. Too bad this year Jeep has all those catalytic converters on it or else I could have used a real header.

 

[jeepdreamer]

I was gonna mention that the machine shop didn't clean the block very well but your on it.
This is the best place I've found for exhaust related stuff, maybe it helps ya out?

http://performance-curve.com/

 

[BuckeyeBullet]

Thanks, that is a useful site. Wish I'd known about it a couple years ago when I welded up a custom X-pipe exhaust system for the Lincoln Mk VI I was driving then. Not an Expo vehicle, although that didn't stop me from taking it off-road now and then in PA.

Now, here are some more photos of my Jeep. If it looks lifted, that's just because the engine is out! It is all stock although the tires on it are 29" tall. That will hopefully change before too long.

I test fit some components just to make sure I remembered how it went together. Then I took them back off, and once the alternator arrived at my local Napa I mounted it and rigged the cherry picker. An astute observer may notice that the flywheel cover plate between the engine and transmission is missing in the second photo. Yeah, I got the engine installed and bolted in before realizing I forgot that plate. ARGH!! The engine had to come all the way back out so I could get that in there. I also removed the remote oil filter lines while it was out because they had some interference with the Jeep's frame. Going to try and get that solved tomorrow. The valve cover also needs some prep and paint. It will remain black, but I'm thinking of putting orange on the raised ribs that run along the top.

 

[Eaglefreek]

Looking good so far. What cam did you choose?

 

[jeepdreamer]

Funny... I just got done putting mine all together today! Couple of notes... Make sure you look for the little decal that shows the proper routing of the serp belt. I did mine about ten different ways and thought I was gonna have an aneurism! If you don't route it correctly the belt will never even come close to getting tight. Also, put some lube on the adjuster under the power steering pump and use an air ratchet until you get close. Otherwise you'll be turning for days! Its lookin' really sharp... can't wait to see it finished. Now when you gonna build mine!?!

 

[Harmgrissom]

Very nice build from the ground up. I like that. Are you going to paint the outside of the XJ that same Hemi Orange :Wow1:

 

[poriggity]

A Hemi Orange XJ would rock. Nice job on the rebuild.

 

[BuckeyeBullet]

Looking good so far. What cam did you choose?

It is a Crane cam #753901T, grind #H-260-2. The specs at .050 are 107/204 deg (intake) and 117/216 deg (exhaust), max lift/duration. Comparing the figures to the stock cam the Crane should give slightly better low-midrange torque but basically it is close to stock. With the headers and a good intake filter system it should go pretty well even after I put 31" tires on it. I want this to be a dependable wintertime driver with weekend trail use so I didn't want to put a radical cam in it.

 

[BuckeyeBullet]

Thanks for all the compliments guys (and/or gals)! I don't know about a bright orange expo rig...then I'd have to get my RTT in a Confederate flag fabric or something. I got a few more parts put on yesterday, cleaned a locomotive boiler today, and I should be back on the Jeep tomorrow on my days off. Most of the right side of the engine is done now, I just need to buy spark plugs and assess the original starter. I cleaned the grime off the starter today but I want to open it up and see if it looks like it just needs a couple replacement parts or if I should get a new one.

The remote oil filter setup was a little bit of an issue to get plumbed, and it's still not that great. I think it'll be ok but we'll have to see. I would have run one of the hoses down under the engine mount but I noticed the suspension link has previously come up and hit the oil pan. The brass pipe fitting would have been directly in the path of that, so I decided to run both hoses up and over which called for a very close fit on the clean oil side. If the suspension was lifted a little that wouldn't be a problem...

 

[Eaglefreek]

It is a Crane cam #753901T, grind #H-260-2. The specs at .050 are 107/204 deg (intake) and 117/216 deg (exhaust), max lift/duration. Comparing the figures to the stock cam the Crane should give slightly better low-midrange torque but basically it is close to stock. With the headers and a good intake filter system it should go pretty well even after I put 31" tires on it. I want this to be a dependable wintertime driver with weekend trail use so I didn't want to put a radical cam in it.

That cam should work great. Somewhat similar to mine. Did you use different springs? I've got the Comp Cams 68-232-4 in my Eagle and it is supposedly right at the edge of the stock springs limits for lift.

 

[BuckeyeBullet]

I'm assuming they are stock springs, but they are definitely new. I'd never re-use old springs that are "used to" a particular cam grind. The springs came with the cylinder head pre-assembled from Clearwater. If they break...fix it faster right?

 

[jeepdreamer]

Lookin' good! I gotta say that after today I envy you your oil filter adapter!!!! My 02 XJs was leaking and I tried to pull it off to check the O rings etc... Took me over 3 hours just to get it off and I ended up having to make a tool just to break the stupid bolt loose!I Sooooooo didn't want to put the old one back on!