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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.
I had a 00 TJ with the 0331 head and at least 1 "serious" overheating experience. Never cracked. 302k and the engine ran like it did when brand new. It IS possible to avoid the crack.
All the advice here is good, follow it... keep us posted. You may be able to get a new head from the U.S. shipped over if you do need a new one. It may be expensive, but I'm sure it can be done.
If you haven't taken anything apart yet you can shine a light down the oil filler cap on top of the valve cover. Directly below the hole you can see the cylinder head between cylinders #3 and #4, where they most commonly crack. A crack there should be easy to identify by a tan or milky line along the crack. In late 2001 Jeep made a change to the head because of the cracking, if you see TUPY cast into the head between #3 and #4 (pictured below) it is a revised version of of a 0331 head less likely to crack. If there are no markings it's probably the original 0331. As for the gasket and heater core use the advice from posts above mine, but sounds to me like oil is contaminating the cooling system but wouldn't appear that coolant is getting into the cylinders. I checked my 2001 XJ yesterday and found that in have the TUPY version of 0331.
if i look up my Jeep it sais build year 1999 model year 2000 so it's not a lait 2000.
Of course I could buy one from the US but it would cost about 1200-1500 dollars because of taxes over here. I envy you who can take your jeeps rolling down mountains and then order parts for mo money at all. In Sweden parts are at least up about 150%
I have found one store selling a head in germany but it would be like 1200dollars.
Even touch Sweden is a small country we love our jeeps and there are quite big communitys online here about jeeps so im sure I can find a2 used head somewhere. What model year fits? And which models should I keep away from?
Also I need to mention that im a lucky owner of a 1992 Wrangler YJ in a rare good condition so I can still go jeepin. 🙂
Actually there are 3 kinds of 0331 heads. Those that are cracked, those that will crack at some point, and those that say "TUPY" on them. If you use a strong flashlight or in direct sunlight and look down the oil filler cap, you will see the flat section between cylinders 3 & 4. This is where a crack most often happens, right in the center of the head. Here is a picture of a TUPY head made by Chrysler in 2002 to fix the problem, even though they said there isn't a problem. You will see the TUPY cast into the head right where the crack usually forms, but notice the 0331 mark in the upper section of the picture. It's been said that these heads crack after a serious overheat, but my feeling is the cast iron exhaust manifolds used on the 99-04 engines causes a lot of excess heat to remain in the head and that is the major cause of the cracking. Just my humble opinion however.
There is an alternative cylinder head available from Odessa Cylinder Heads in Clearwater FL (727) 556-2909. This head doesn't have the 0331 markings on it. You can use an earlier 0630 head but you'll need an earlier exhaust header as well. IDK what your emission standards are so it depends what you can get away with for exhaust. Your intake manifold will fit. The last I checked the Clearwater head was around $600 USD complete with valves and springs and free shipping in the US. (shipping weight 90 lbs.)
When the head on my 2000 WJ cracked, I got lucky because it cracked into an exhaust port, but not into the valve area resulting in clouds of white smoke and coolant dripping out the tailpipe.
I made a new compression test today. It varies from 162-174 psi. That can't be to bad?
Since I know my electric fan isnt working as it should. I removed the relay so i could put a peace of cable to start it manually. Then i started the engine and monitored the temp with help from a bluetooth device so i could stand in front of the car and start the fan.
At 95 c I started the electric fan but temp went up to 108c. Then i increased the rpm and temp dropped to 89c.
Can all of this be a overheating problem due to faulty electric fan? Engine ran hot which led to boiling coolant which caused bubbles in filler cap? Im gonna put a switch for the fan so i can go for a long test drive and monitor the temp closely. As long as the engine runs great and it does'nt run to hot everything is ok or?
I will lift the valve cover and have a look through but I think i will wait with lifting the head for now.
I Googled compression for 4.0 engine and the compression look a bit high but very close to what it should be. Good idea hooking up the electric fan to a switch, I'd suggest trying to find an rpm for the fan that can keep the engine between 90 and 98 celsius. I'm not sure if this is the only cause but I do know the 4.0 engine can struggle with overheating issues easier than most engines. I'd suggest if the fan alone doesn't fix the issue, looking into other cooling system components, with everything working well together the engine should be able to stay cool enough for almost any situation.
Yes overheating seams to be an issua so I will monitor the temp closely. My comp tester is a very crapy one so it might not be super acurate but all measurments was close so the main thing would be that I did'nt have big variations.
As far as pil goes i have only looked at the stick and down in the valve cover through the filler cap and everything looks fine. Im going to change the oil and filter soon because I dont know when it was changed before i bought it.
Just now when the engine got cool I looked in the radiator cap and saw foamy bubbles again 🤔
Could bubbles come from a leak somewhere in the cooling system? For example heater core, radiator or a worn hose? I can't smell any exhaust in the bubbly foam but thats because I lost my sense of smelling thanks to a covid infection last easter. 😃
You could do a leakdown test and see if you get bubbles. Some compression testers have fitting you can connect an air hose to. It does sound like a failed head gasket and possibly a cracked head. Do you smell coolant inside the Jeep? You may have a failed heater core as well.
You could do a leakdown test and see if you get bubbles. Some compression testers have fitting you can connect an air hose to. It does sound like a failed head gasket and possibly a cracked head. Do you smell coolant inside the Jeep? You may have a failed heater core as well.
I can't smell anything at all unfortunately. But it did'nt build up moist inside when the engine did'nt run too hot today.
I will take a test drive as soon i've fixed next problem...i broke both upper bolts on one side when i was trying to change rear shocks today. Kind of weak construction i would say. The front shocks was changed without any problems though.
I found that drilling and tapping (by this I mean, drill just enough to cut new threads into the metal) it was easier than drilling all the way through. This may be unique (exclusive) to me since a previous owner welded new nuts and the weld was solid but a little sloppy/imprecise.
I mention the idea of getting a U.S. Head to say, AN option (but maybe not the BEST option) is to have one of us purchase and ship a head directly to you. Clearly there is a question of trust (hundreds of dollars exchanged with strangers) and shipping a heavy item overseas is going to be expensive. Is that cheaper than 1200 dollars or 1500 dollars, maybe, I don't know. But I'll happily buy and ship if you send me the money first if that will help you out.
So the fan question.
Yes, a weak electric fan can make a difference.
No, it is not likely to be a cause of normal driving overheating. If you are driving normally and do not use the A/C, the electric fan should not even turn on. The mechanical fan should be enough to maintain proper temperature.
I feel like you have a head issue based on what you have said.
Actually there are 3 kinds of 0331 heads. Those that are cracked, those that will crack at some point, and those that say "TUPY" on them. If you use a strong flashlight or in direct sunlight and look down the oil filler cap, you will see the flat section between cylinders 3 & 4. This is where a crack most often happens, right in the center of the head. Here is a picture of a TUPY head made by Chrysler in 2002 to fix the problem, even though they said there isn't a problem. You will see the TUPY cast into the head right where the crack usually forms, but notice the 0331 mark in the upper section of the picture. It's been said that these heads crack after a serious overheat, but my feeling is the cast iron exhaust manifolds used on the 99-04 engines causes a lot of excess heat to remain in the head and that is the major cause of the cracking. Just my humble opinion however.
There is an alternative cylinder head available from Odessa Cylinder Heads in Clearwater FL (727) 556-2909. This head doesn't have the 0331 markings on it. You can use an earlier 0630 head but you'll need an earlier exhaust header as well. IDK what your emission standards are so it depends what you can get away with for exhaust. Your intake manifold will fit. The last I checked the Clearwater head was around $600 USD complete with valves and springs and free shipping in the US. (shipping weight 90 lbs.)
Great info. Thanks slot. I have checked down the cap and i did'nt see anything. I will check again. If you say that the manifold could be the problem for heads to crack a faulty electric fan would not help the issue for sure.interesting thought.
I found that drilling and tapping (by this I mean, drill just enough to cut new threads into the metal) it was easier than drilling all the way through. This may be unique (exclusive) to me since a previous owner welded new nuts and the weld was solid but a little sloppy/imprecise.
I mention the idea of getting a U.S. Head to say, AN option (but maybe not the BEST option) is to have one of us purchase and ship a head directly to you. Clearly there is a question of trust (hundreds of dollars exchanged with strangers) and shipping a heavy item overseas is going to be expensive. Is that cheaper than 1200 dollars or 1500 dollars, maybe, I don't know. But I'll happily buy and ship if you send me the money first if that will help you out.
So the fan question.
Yes, a weak electric fan can make a difference.
No, it is not likely to be a cause of normal driving overheating. If you are driving normally and do not use the A/C, the electric fan should not even turn on. The mechanical fan should be enough to maintain proper temperature.
I feel like you have a head issue based on what you have said.
Man thats kind of you offering help like that. I was looking at quadratec for a new head today but i Will wait to order till I know for sure i have a bad head. The shipping will of course be expensive but the worst thing living in Sweden is the taxes and import fees. If the head cost 500 and shipping costs another 500 i will have to pay almoast 30 % in taxes with shipping cost included! Thats crazy! crazy!
12-10-2020 | 05:58 PM
