dave1123

I think I may have a cracked head on my '00 WJ 4.0 and I'd like to narrow down possible replacements for it. I think mine is the 0331 head that tends to crack around the 3-4 cylinder valve area. I was starting to loose a bit of coolant from the reservoir about every month but now it's getting worse. I haven't pulled the valve cover to verify it yet, but I want to be prepared if I need a head.

I went to Clearwater Cylinder Heads website because I was told they make a heavy-duty casting for it, but the website calls the 6 cylinder engine a 4.7!! Also, there have been some complaints about the company.

I kinda' figure the dealer would scrape out my wallet, so what's your choices? I'm open to any suggestions, but will check them out before I spend any money. Thanks for your time.

Dumajones

I went with Clearwater and seems to be doing real good, the casting is heavy duty on mine, But I did see the bad reviews about Clearwater so
I will just keep up on cooling maintenance and hope for the best.

But it sounds like a head issue if you have the 0331 or at least the gasket. But that's how mine started to go.
Little by little coolant being gone out of the reservoir then more and more frequent then the oil pressure started to go.

dave1123

Yeah, that's why I wanted to catch it NOW, before I start having oil pressure problems. I have a Mopar sensor and she's showing 55 psi on cold startup, 40 after warmup at idle, and 50 at 60 mph. That's with 170K on her with 5W30 Syn. It shows no milkyness on a drain at 5K either. It does, however seem to steam a lot from the tailpipe in the bitter cold, but IDK if that's normal or not. One mechanic tells me the crack can be internal into the exhaust port, but, again, IDK.

bigbadon

Pull the O2 sensor and look at it. If it is glazed and smooth looking that is the tell-tale sign of coolant passing through the exhaust.

dave1123

Thanks for that. I'll have to check them both.

rangermonroe

Dumb question/suggestion, maybe, but why not have it welded? Dance with the one that brung ya.

dave1123

That's an option I'll consider after I find out if the crack is really there and cracked into the valve spring area. If it's internal, it'd be a PITA to weld inside an exhaust port, IF that's possible. I was actually looking for a source for a new head so I'll be aware of cost and lead time involved.

The major problem is this is my DD and only vehicle that I use for my business. Time is important and trying to get my sister-in-law off her ***** to help me chase parts is next to impossible. My best bet is to take it to my buddy's shop and let him do it. He only charges me $50/hour and could do it in one day IF I brought him the new head. I'm too old to be doing this **** in my driveway! That freaking head weighs 85 pounds. I could handle it if the motor was sitting on my garage floor.

dave1123

Okay, an update on my 331 head problem. My valve cover is leaking and I usually lose about 1 qt in 5000 miles. I'm 450 miles from my next oil change and it's about the same, not higher in level as you would expect if coolant was leaking into the oil. My oil pressure is still excellent (40 psi hot idle), HOWEVER it seems to be going thru coolant about twice as fast now and after idling for about an hour, there's a 6" diameter puddle of water underneath the tailpipe.

In my research for a new head, I was directed to Alabama Cylinder Head, but their website seems to not function. Mopar doesn't make them anymore since they stopped producing the engine and all I can find are remans. Supposedly, any 331 heads made AFTER 2001 were recast and don't have the problem. Also, the 630 heads made before '99 will fit but there is a port alignment problem with the manifolds and they don't have the mounting bosses for the coil pack. Monday, I'm going to talk to my dealer's parts guy and ask what they use for replacement.

Clearwater Cylinder Heads don't list a 4.0 head on their search menu so I'll have to call them.

From what I understand, in redesigning the ports on the 331, they created a weak spot in the casting between the #3 and #4 exhaust ports resulting in cracking. This was rectified in 2002 without mentioning it to anyone. The newer head still is listed as a 331. Mopar won't verify there is a problem. There is a 331 head cast in Brazil and stamped "TUPY" that doesn't seem to have this problem. They increased the nickel content in the casting metal.

SO, if your looking for a used head as a replacement, find a 2002 or newer OR a head stamped "TUPY" underneath the edge of the valve cover.

I'll keep you guys updated as this progresses.

Snajo

Sorry to thread jack, but I'm in a similar spot. I ordered the head linked below. I'm confident it'll work one way or another, but I didn't consider gasket and possible exhaust manifold differences when I ordered it. I did call clearwater and they said that it was an older style head remanufactured to fit the 99+ 4.0l, meaning to me 00-01 cherokees, 99+ grands, and 99+(?) wranglers.

Basically, am I going to need to go with an earlier style exhaust manifold or header to match the older style head or can I expect it to be modified to match the one I have?

My 2000 is the federal emissions version without pre-cats and without the two additional O2 sensors, so I won't be breaking any laws if I have to go to an earlier style exhaust.

The only reason I'm concerned is because I don't have another vehicle to drive, so I want to clear the big questions up before I take it apart. I'm good enough walking and biking, but don't want to make a lifestyle of it.

http://www.cylinder-heads.com/cylind...ms-fits-99-07/

Dumajones

My 2000 is fed only.
I went with the head from Clearwater. Everything was fine, bolted right in. Even had the holes for the coil rail to bolt up.

Snajo

Thanks! I appreciate it. I think they could mention that their 0620 heads are made to replace 0331 heads. Either way though, I'm looking forward to it, just nervous.

dave1123

Clearwater's recast 0331 head is guaranteed for 60 months not to crack. Their head is a brand new casting with more metal in the areas in question and comes complete with valves for $455 with no up-front core charge. They supply a return shipping label as well. You have 30 days to return the core or be charged for it.

I will be ordering one as soon as I line up a substitute vehicle. Anyone want to rent me their XJ or ZJ for a couple of days?

Snajo

I just called clearwater and got my order straightened out. I ordered the wrong head - a 4.0 head that has been remanufactured for to fit an old 258/4.2L. The person I spoke with was very helpful and is going to change the order for me. I'll be getting the same new head that it sounds l like you're ordering.

I'm doing this for my XJ, but as far as this is concerned, I don't think there is any difference. I drove a WJ 4.0 for about six months, but sold it and went back to an XJ. The WJ was a nicer vehicle in many ways, but the XJ was just more fun!

dave1123

Yeah, don't forget the WJ weighs 4000 lbs! I'll bet your XJ is a lot less than that!

dave1123

I just received my new Clearwater 0331 head and it looks super! $455 and free shipping BOTH ways! I ordered and got all the rest of the parts from Rockauto. I'll keep you updated after it's done.