Being over cautious in this situation is a good thing. Like I said in post #10 DO NOT keep running it until you are 100% sure that you don't have a bad head or head gasket. You think it will be costing you a lot to repair it now what to see how much it will cost if you keep running it with water in the oil.

 

Jamurrin - I agree with you 100% - but so far, I can't say for sure I'm leaking coolant as fast as I may have thought. I'm guess-timating that the overflow was "around" the full mark when I first looked, but don't know for sure. I know it was around the add level when I last looked - BUT - that was when I just got home & the engine was nice & warmed up. I can't remember if I checked it first when it was cold, or if it was warm - which could explain the drop (if I checked when the temps were hot vs cold - right?)

Also - I don't know if my oil level has gone up, down or stayed the same as I don't have a baseline to say where it started.

So far, the jeep hasn't leaked a drop of fluid on my driveway, the heat blows hot, the oil pressure is good both while cold & hot, the temp gauge has never reached 210, and once its warmed up, I haven't noticed any more "white" smoke (so the original sight may be attribitable to cold mornings and a bit of panic-mode).

If there is one thing I want to avoid, it's turning ANY issue into a bigger one - but first I think it's best to figure out exactly what issue I 'may' be looking at (if any at all), then plan out my next steps.

Hope that all makes sense! I appreciate all the input, suggestions & feedback. The info on this site is awesome!

 

I've had to fix 2 cracked 0331 heads so far, and I gotta say, It sure does seem like the head on your jeep may be cracked. When my jeep had a cracked head, the only symptom that i noticed was a milky residue on the oil fill hole cap... no coolant loss.

The best thing you can do is take a nice flashlight, turn your jeep on and let it warm up, then take a look through the oil fill hole. If the head is cracked, you will most likely see coolant weeping out of the head into the oil between the 3rd and 4th cylinders.

 

Ok, I changed the oil - no sludge, no milky froth, just looked like oil that had been driven on.

pulled what I think were the 3rd & 4th plugs (counting back from front of engine.) They weren't oily or black, but not sureif they looked "steam cleaned" either.

Added antifreeze to the fill line, and made note of oil level. I'm going to call my mechanic to potentially get a pressure test done while I try to locate a tupy head for a "worst case scenario" situation. I'll keep a close eye on levels and at the first sign of trouble, take the necessary action.

 

Welcome to the forum and to the cracked 0331 club! Either way you need to pull the head and while the head is off you can get it inspected and tested for crack. If it were me, I would hope for the best but expect the worst. I know my '00 XJ never overheated since I'm the original owner but the head still cracked. But then again mine had no white smoke...

 

Right now my 00 cherokee is misfiring on number six and it looks like my coolant and oil are mixing slightly it's a bad misfire and I'm blow some smoke can't really tell the color but it smells bad it's got me puzzled I have another post on here about it just looking for more info

 

Real quick question for all of you - will any Jeep 6-cylinder "TUPY" stamped head fit my Cherokee? E.g. - one off of a 2003 Grand Cherokee?

I'm driving a 2001 Cherokee Limited, and think I may have found a replacement head, but don't want to buy something that may not fit.

If not all TUPY heads are direct swaps - is there something very specific I should be looking for when looking for when searching for one?

 

They should. It is still an 0331 head, just a little stronger in the weak areas. There are also plenty of aftermarket heads available online in the $400 range. Most of them are thicker in the weak areas also.

 

Thanks for the quick answer, Sienna. A couple more - What about the non-TUPY stamped heads? I'm just curious if a 2003 Grand Cherokee has the 4.0, but the head isn't TUPY stamped, is that then the same 0331 casting that is known for cracking?

 

If it isn't TUPY stamped, it is most likely the original 0331 head. You can also check the casting number on the drivers side of the head near the bottom. I forgot exactly where it is, but it shouldn't be too hard to find.

 

How is the "tupy" head identified? Is this a OEM/replacement head?

As to Clearwater/Oddessa cyl heads, tho I can't vouch for the I6 head, my son did get 2 heads for his Ranger V-6, which stock suffers a simular design flaw.

 

YES!! Don't go by the 2003 model year of the vehicle. Use the date code on the engine...the OEM engine could be up to TWO years older! If it is a early 2002 engine chances are likely that it isn't a tuppy.

 

I just did a head swap to a TUPY head on my 2000 XJ. To me, you have the EXACT symptoms mine did. A test you can do is to get the engine up to running temperature, take off the valve cover(MUCH easier than pulling the head and getting it tested) get a towel (as to not burn your hand) and Squeeze the coolant tubes to force coolant through the possible crack. I did this and a RIVER of water came through in between the 3&4 cylinders. Taking off the valve cover and doing a quick check like this is a LOT less time consuming than taking the whole head off.

Now, it's not 100% NOT cracked if you don't see anything, but 90% of the time these things crack in the exact same spot according to my research, and this could very well put to bed your "unsure" situation.

If you have any questions on the swap let me know, I literally JUST finished mine, and it was for the most part pretty easy.

 

^^^ this. Only TUPY stamped factory 0331 heads have the beefier material where its needed. It was a revised casting in later years to combat the cracked head situation. Of course Cleawater, and Alabama (now a different name that I forget) make these stronger heads as well. But I've heard horror stories about their customer service and fit and finish.

 

(How is the "tupy" head identified? Is this a OEM/replacement)Tupy will be stamped on the inside of the head. Tupy is the OEM fixed Head.