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Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.
Just picked up a 2000 Cherokee classic with 205,000 miles. Everything was in good shape interior and exterior, and seems to run without issue. No check engine light. Only major issue is the heater core needing to be replaced.
After having it the last couple weeks and doing some research Ive come across the 0331 cylinder head issue. I checked and the head is indeed stamped with 0331 so I know I’ve got the head with potential issue. Trying to figure out what the best course of action to take with it. Currently everything seems to be working great and running without issue. But plan on keeping and driving this Jeep for many years to come. I’ve gots lots of plans on upgrades, but wanna put my money into the right place as far as making sure it’s gonna be a solid reliable running vehicle before anything else.
I’ve looked into replacement heads, Clearwater seems like a great option that many have used. Would just a straight head swap be best route? Do I need to worry about any damage on the bottom end if I do have a cracked head and just haven’t realized it yet?
Oil pressure seems to be within the parameters of what is considered “healthy”. But I know our gauges aren’t always accurate and should check with a mechanical gauge to verify.
Not sure if this is the right route, or if I should just leave it alone. Seems like swapping engine could create some issues with finding something that’s a direct plug and play setup(I’ve got coil packs) and would have to do further modifications to get an older engine to work without giving off check engine codes. I’m in an emissions county and need everything to work property to get tagged and registered for the year.
Everything seems to be OK so for the moment stop worrying about it.
For the next couple oil changes get the oil analysis done.
Most of us use Blackstone Labs.
Check with a mechanical gauge and maybe to a compression test. Throw a block test into the mix maybe.
3 symptoms you always read about.
Milkshake oil.
Little or no oil pressure at a very hot idle.
Unexplained loss of anti-freeze.
Remembering that the last two could be other things and technically milkshake oil possibly could be a bad head gasket.
But with a 0331 head we just go right to the bad place. LOL.
Also 13 PSI is acceptable oil pressure at a hot idle. Low end of acceptable IMO but still acceptable.
Have you had the valve cover off?
If not look down the oil filler hole and see if you can see the letters TUPY.
That would be a good thing.
Coolant getting in the oil will trash the lower end pretty quick.
But I would not replace a head just for the sake of replacing it.
But that is me. Despite the Jeep being my DD and only vehicle I own if she went down it would not really matter.
Being older, not having a life, being kinda retired, and living a 1/2 mile from my little part time job makes this possible. MLOL.
The other option is a TUPY head. Can be found on later '02 to '04 WJ's and later '02 to '06 TJ's.
Thing to keep in mind is that this is a used head.
So do you take a chance and use it as is?
At least get it checked by a machine shop?
Or just get it rebuilt?
Could cost almost as much as a Clearwater when it is all set and done.
Now just cause the opportunities have presented themselves I have scoffed 2 TUPY heads
One off Craigslist for $50 off a WJ with a broken piston top and the other that I got for free off a '04 TJ with a lower end knock.
Now they could be usable as is, maybe could be rebuilt, or could just be door stops.
Will worry about it if and when the time comes.
You 2001 is still the old style block with the 0331 head on it so it will comply with CA emission standards and uses cast iron exhaust manifolds because of the short run to the converters. An older head will bolt on, but there are problems with accessory mounts and exhaust ports lining up if you don't. If you nail a used "TUPY" head, it will cost about $200 to get it reconditioned or buy a "Clearwater for just over $500 complete with new valves and springs. My opinion is to have something standing by just in case. Not all 0331 heads crack, but it's a time bomb with a short fuse. BTW, the "TUPY" is also a 0331 head, but has more nickel in the steel it's poured with. This picture shows the "TUPY" logo and also the 0331 numbers. These heads were poured by the Tupy Foundry in Brazil for Chrysler. The Clearwater head is made by Odessa Cylinder Head in Clearwater, FL and has more metal in it where it needs to be. It weighs more than the original 0331 head and isn't marked as one.
By the way, your jeep looks just like mine is supposed to! Same color with more metal, LOL! My rear wheelwells are so bad I could put 33's on it without a lift!
Ok thinking of just getting a Clearwater when I get the opportunity. Is it worth just going ahead and swapping it out when I get a chance before it cracks? That way I don’t have to source a good bottom end as well? I’m guessing I should be able to reuse my current block as long as I don’t wait till my current head cracks and create more issues.
Ok thinking of just getting a Clearwater when I get the opportunity. Is it worth just going ahead and swapping it out when I get a chance before it cracks? That way I don’t have to source a good bottom end as well? I’m guessing I should be able to reuse my current block as long as I don’t wait till my current head cracks and create more issues.
You could, but just remember those rings have 200K on them and the added cylinder pressure of the head with new valves may cause more blowby than you'd like. I think you've been lucky with that head so far. Just drive it and stop worrying until it fails. Then you can deal with it later. If you plan on keeping the jeep for a long time, you could buy the head now, then use in on a rebuild later. I got lucky with my WJ because the head cracked into the exhaust ports and not into the valve area. Lots of steam out the tailpipe and coolant dripping out the pipe.
Have you investigated weither or not you might already have a "TUPY" head? Like maybe the PO already changed it? Look down the oil filler hole with a flashlight.
I did looked into oil cap but couldn’t see any markings. But it was also super gunked up so hard to tell. I’ll change the oil and let it go through a full cycle (3000 miles?) and get the oil tested to see where I’m at.
If I just wait it out until it does have problems, which hopefully it lasts awhile, what would be the easiest way to swap engines. Another engine out of a 2000 or an 01? Hopefully low mileage. Or trying to make and older engine work with my newer accessories
When you change your oil add one quart of Marvel Mystery Oil (MM) in place of one of the six quarts of oil the 4.0 takes. It'll help get rid of the gunk your seeing. Then yes have it tested.
I did looked into oil cap but couldn’t see any markings. But it was also super gunked up so hard to tell. I’ll change the oil and let it go through a full cycle (3000 miles?) and get the oil tested to see where I’m at.
If I just wait it out until it does have problems, which hopefully it lasts awhile, what would be the easiest way to swap engines. Another engine out of a 2000 or an 01? Hopefully low mileage. Or trying to make and older engine work with my newer accessories
My thinking is to stay away from '00's or '01's completely.
They all have the 0331 head so I don't really see the logic in that.
Swapping out the necessary components to an older engine that is on the list of what will work.
Google will give you that info.
Question has only been asked like a zillion times. LOL.
There is one thing I might try if I go with just dropping in a boneyard engine though. If and when the time comes.
This lets you run an older head with the '00 and '01 exhaust.
Still have to swap out the components though too.
And have to fab up something to run the coil rail.
Or you can do the Viper Coil Mod. Going to doing that to my '00 when the weather gets warm.
I picked up a 0630 head off a 99 XJ at the boneyard today for 43.00 that I’m going to put on my 2001 while I’m changing out the leaking expansion/freeze plugs. Get a light and lay under your Jeep on the drivers side and look up at the side of the block to see if you have any leaking from rust spots. Once those leak too much your going to lose all your coolant and overheat your engine
Doesn't the 0630 have the paired center exhaust ports, or does the adapter solve that problem?
I am going to assume that cause it does say at the link about both the 0630 and 7120 heads so.....
I came across this years ago when I bought my '00. Not cause I had a problem but figured best
to educate myself about the 0331 head and what options were out there if and when it ever does
become a problem.
Also too I noticed that he has something for dealing with the coil rail on an older head at that site too.
03-23-2020, 03:44 PM
What should I do about my 0331 head 2000 xj
