So a year ago I purchase a 2000 Cherokee Sport 4.0 for $400 that was clean and straight but had overheated. I knew going into it I was looking at a water pump and head gasket at least which is not an issue for me. The vehicle has 186,000 miles on it and it has sat for the last year. I started doing some research on the head work and discovered the casting issue with the 2000-2001 heads on that engine.

I have the head removed and do not see any obvious issues between #3 & #4 on the top of the head, I know that doesn’t mean a lot. The head bolts are not painted so this looks to be the first removal. I have confirmed that my head is the 0331 casting. I drained the oil last night and it was black as expected but there was no sign of water or antifreeze in the oil or pan. I have never heard this engine run, but I suspect that the water leaked out of the water pump which caused the overheat issue that the previous owner experienced.

So now to my question. With the known head issues for this year range vs the mileage this engine has with no known head issue, do I bother pressure checking the head or just boat anchor it and go with a TUPY head from a junkyard? I don’t want to go with an earlier 0630 head, and there is no need since there should be plenty of available newer ones in the JY. My thinking is that the head made it this long maybe it’s a keeper and worth re-using?

 

I have 200k on my 01 and I am still running the 0331 head. I have never got it hot though. If you have the coin and want the piece of mind I would go ahead and put a new head on it since you already have it off. That being said, I don't ever plan on changing mine unless things go south.

XJ's get a bad wrap with regards to overheating but if you take care of it you won't have any problems. For what you have in the jeep, I would replace the head, put a new radiator in it, water pump, and thermostat and drive drive the wheels off of it.

If you don't want to spend the money on the head right now and if you drained your oil into a clean pan you might get a sample and send it to Blackstone. They can tell you if there is any coolant in the oil.

Don't know about your neck of the woods but around here a TUPY head from the JY will cost as much as a Clearwater....they are like gold.

 

I use the Pick-n-Pull around here, Dallas TX, I love their flat rate prices. If I can find a head it would only be $35 with a $5.00 core, problem is going to be finding one, and then getting it off in the JY. I think I'll go this weekend and look around. If I can't find one then I'll go Clearwater or another aftermarket replacement.


I'm fixing this up for my daughter and I don't want to have to redo something due to cutting a corner that shouldn't have been cut. Thinking about it, re-torqueing the old head might be just enough stress to crack it on assembly since it's been hot. That isn't a guarantee that it's not already cracked from the overheat, I just can't see it yet. If I can get one in the JY I'll get it magnafluxed and tested before assembly to make sure it's good. I think I might be throwing the money away doing that for the old head with the weak point issue.


Hmm, I can do the valves myself but thinking by the time I pull it in the JY and have it milled, pressure tested, and magnafluxed, I might have enough time and money in it that it would have been better to go with a Clearwater shipped to the house and ready to install.

 

This should be a red flag before you start throwing all kinds of time and money at it. Peeps don't just park a usable vehicle, engine is probably trashed.

 

No, this was her daily driver when it broke, single mom without a lot of money for repairs. We sold her our good 2005 Neon, as good as they are, for cheaper than her repair bill for the Cherokee. I wasn't interested in buying her Cherokee at first because it's a Chrysler, not really a fan of Chrysler engineering, but she offered it at a price I couldn't refuse, and it helped her out since Firestone was bugging her to get it out of there. Even if it needed an engine overhaul, I would still break even or come out ahead since I do all the work myself. It sat for a year in front of my house while I built a 20x40 foot garage since the existing garage was converted to a game room and I had no room to work on anything. Now that the garage is done, the City decided to code me on the Jeep so I moved the it into the garage and started working on it. The timing was perfect, I didn't have room in the garage because of construction stuff until now. I'm pretty careful about what I buy used, I don't mind helping someone out but not at a loss to me. I was a professional mechanic for 20 years before I went into computers for better pay so I know the in's and out's of used vehicles, I've haven't gone wrong so far.

 

So I bought a head from Clearwater, fine head work if you ask me, and bolted it on. Had trouble with the torque on the center bolts under the valve cover, I got them to 100 but they kept turning and never clicked. I've had the threads pull out on me on one engine in 30 years but it was an aluminum engine that had been seriously overheated, never a cast block. I left them alone, it may cause problems later, if so there are plenty of 4.0 block in the junkyard. Right now it purrs like a kitten. I forgot how smooth a straight 6 runs. Drove it to work for the first time today and it drives very well with plenty of power and get up, nice an nimble, not at all like my big F150 dual cab. Oil pressure is 18 with the engine hot at idle and 40 when running at 65 mph, temp right at center gauge, 210? Very nice, daughter's going to love it.