I have the dreaded 0331 head and the previous owner already had the head rebuilt once. The 2000 original motor I have currently knocks and does not hold oil pressure over 10 psi at idle. The 92 donor motor is coming from craigslist and I would like to just swap the motor to my jeep but i know that there are different things that the motor has like distributor etc. Any way I was just wondering if anyone had some insight on what all would need to be done to make this work. Also this is my first post so I apologize in advance if I have posted this wrong in anyway.

 

Does your XJ have EPA emissions with TWO O2 sensors (front and rear), or does it have California emissions with FOUR O2 sensors and two extra catalytic converters? That will make a big difference in what you have to do to make that work.

 

following!!!! I also have a 2000 xj with the 4 million cats of course! what are my options? screw that whats the best swap cuz i dont have to pass emissions here anymore

 

I believe that my xj on has the two O2 sensors... I can check tomorrow. Im just trying to figure out my best options. I don't really want to rebuild my 2000 motor because the 0331 head is going to be a reoccurring problem. Thanks for all your help.

 

Be very careful about your state emissions laws. In CA this would be illegal since you aren't allowed to replace any parts (engine included) with an older year part. It's ok to go newer within guidelines but not older.

The 2000 XJ was meant to use the 0331 head and compatible intake and exhaust manifolds. I'm not positive but it may be like my 2001 which has three cats and three O2 sensors. You can locate a known 2002 or newer head. They improved the castings after 2001. Some of the improved heads have TUPY cast into the top right in the middle among the valve springs.

There are others that don't have the TUPY but are improved. Look for the casting date. It should be a date after July 2001.

 

The version with the three cats had CA emissions. That was an option in 2000 and became standard in 2001. There are a lot of EPA version vehicles out there from 2000, and they are much easier to deal with when modifiying.

This is not true. If you find an 0331 head that does not have TUPY cast into the top of it, it is not a TUPY head. The TUPY heads were made by the TUPY foundry in Brazil. The original 0331 heads were not. The TUPY heads were marked that way by the foundry specifically to differentiate them from the flawed head.

That's easy. Just use your 2000 short block and replace the head. The easiest solution for the 0331 head is to buy an aftermarket replacement from Clearwater Cylinder Heads, which will run you about $450 but will bolt right on without having to mess with the exhaust or coil rail. If the block doesn't actually need to be rebuilt, you can just swap the head out without pulling the motor out of the truck.

You can try to source a used TUPY 0331 from a junk yard if you need to save a couple hundred bucks, but I'm not sure that's really worth it. Either one will solve the 0331 casting flaw and leave the motor just as reliable as the pre-2000 engines.

 

Thanks for all the help! But the motor sounds like a diesel and the main bearings are worn out from the previous owner. I bought the jeep from the middle of no where bone stock with 106,000 on the odometer for $3,000 I felt like i had hit the holy grail.... Got home to change the oil and it was at least 70% motor honey. So I have put 40,000 miles on it like this and now that I have some cash I am figuring it is time to fix the problem before I install the RC lift and tires. So do you think I should buy a master rebuild kit and a new head from the company you suggested?

 

It's up to you. There are many paths to an acceptable outcome. The one you choose will depend on your skills, budget and enthusiasm for the project.

My solution when my 0331 took a dump was to replace my engine with a built stroker in a crate and have a local shop do the swap for me, but that's because I had more money than time, experience, facilities and tools. If I had a full garage and the time to do it myself, I'd probably rather save the money and gain the experience.

So it really just depends on your situation.

 

I thought about the same solution but do not have that did of cash. I do have some cash but not $3,000 for a crate stroker as I am still in college. I wish I did though. I wanted to spend somewhere around $1,000 to $1,500 on the project to still have cash for tires.

 

Here's another way to go...

Google Marshall Auto Machine

They are in Skowhegan, Maine.

I bought a 97 chevy 5.7 from them completely rebuilt because I was in a hurry. I requested brass freeze plugs up front and the rest of the build was great.

They give you a 3 year, 40,000 mile warranty.

The cost for one of our later XJs is $1395.

They shipped my Chevy engine on a crate which I used to ship the old one back. There was no up-front core charge. They paid the freight and arranged the delivery and pick-up both ways.

I have no complaints with their work or their service. I bought my engine a couple years ago so I can't say they still include shipping but my Chevy engine was $1250. and included it in 2013.

I had to do the finish work.....i.e. clean and install the tins, oil pan, rocker covers timing cover and the oil pump. I also had to put-on a new water pump and install the intake and distributor.

They have been in business for awhile and you can call the owner, Joe, and speak with him almost any time.

Just another step out of the box.


+++++++++++++++++++++++++++++++++++++++++++++++ almido All My Dough '01 JX 241k miles unmolested......so far

 

Can we determine if the 0331 head's ports differ from the 91 to 99 motors?

 

The exhaust ports are different. You have to either use the older motor's exhaust manifold (very difficult on a CA emissions version) or get an adapter plate to mate the 0630 to the '00-'01 exhaust. I noticed recently that someone had one of the adapter plates for sale in the member classified section, but I don't know anything about them and didn't realize they existed until I saw that listing.

Here's a drawing of the gaskets overlaid. The reddish one is the 0630.

 

Got a pic of that adapter plate?

 

I didn't, but Google helped.

http://jeepexhaustadapter.com/

 

Hard to see the distinguishing points between the head and adapter in the photo.