(ThE NoRm!)

So got a 2000 xj. Radiator fluid just disappears. No leaks. No milky oil. Wtf? Advice? And also hasn't overheated... EVER...

autosurgeon

Open oil cap with it running shine a bright flashlight straight down. Do you see a bubbly line of something that is not oil? That would a crack and the bubbly line is coolant. That is where your coolant is going right into the engine to eat the bearings and camshaft . do a search there are tons of threads about what to do to fix it.

Firestorm500

1. Replace the head and/or engine.

2. Or sell the Jeep.

Fred/N0AZZ

Sounds like through the engine and out the exhaust, not good! What does the oil look like brown and milky in color?

Klutch

I also have a 2000 XJ and just this past Sunday I found out I have the dreaded 0331 cylinder head crack. Unfortunately, I think you're in the same boat. Your options are:

- Sell it as is with full disclosure that the cylinder head is cracked

- Order a remanufactured head with a "TUPY" casting. This is the casting Chrysler designed to resolve the cracking head issue

- Order an aftermarket head from a vendor such as Clearwater or Promaxx. The aftermarket head is a new, heavier casting which resolves the cracking issue

I would NOT recommend:

- Installing another 0331 head. This is what you will get if you buy a remanufactured head from an auto parts store like NAPA or O'Reilly. Don't bother. The 0331 head will just crack again. It's only a matter of time

- Trying to find a "TUPY" head at your local salvage yard. Everyone else had the same idea long ago and any TUPY heads are long gone

- Trying to fix the problem with "Stop Leak". Don't EVER use that stuff. It just gums up your cooling system. If it actually does stop any leak, it's only temporary

FYI, you'll see many online recommendations to get an aftermarket head from "Alabama Cylinder Heads". This company no longer exists. They are now Promaxx, as far as I can tell.

I ordered my new cylinder head from Clearwater this past Monday. I hope to have it next week so I can get my Cherokee back on the road.

Morris4x4Center

How much fluid exactly do you think it was?

The rad is empty? or the overflow bottle has a crack / leak, and you keep filling it up?

Just hoping you might have something less expensive than an engine head problem if luck goes your way. :-)




...

Klutch

FYI, the cracked cylinder head issue typically doesn't cause the oil in the pan to appear milky. It will typically cause the oil level to rise due to the coolant leaking into the top of the cylinder head. You might also see some milky residue on the bottom of the oil fill cap when you remove it.

Sorry, I really hope it's not the proverbial cracked head issue. Unfortunately, all the indicators point in that direction. This problem is with the 2000 and very early 2001 4.0. So, if you've got a 2000 Cherokee, it's pretty much a given that you'll suffer a cracked cylinder head. No overheating is necessary to cause the problem.

Firestorm500

He said "no leaks".

Luck has nothing to do with it. These heads have a fatal casting flaw.

kcdt58

He also said "no milky oil". It has to be going somewhere...

extrashaky

While I agree with everything else you said, this one is not true. Salvage yards are not static, especially the self-service yards. They are constantly getting in new vehicles and sending old ones to the crusher. I see later model Jeeps with TUPY heads periodically and know there will be more on the way as more of the later model Jeeps reach the ends of their lives.

If you need to save money and don't want to spend the extra for a new one, there's no reason not to search the junk yards. A half hour of your time in the local yard will tell you if there's one there worth pulling.

extrashaky

I did not have milky oil when mine cracked. The oil just turned a little bit lighter color, and the oil level rose. Lack of milky oil means nothing.

Klutch

Good point. In my area, there are no TUPY heads to be found. But in other areas, they might be around and it can't hurt to check. Sometimes I'm just overly negative.

aroundincircles

I had a blown head gasket, with no oil/coolant mix, just missing coolant. Pull your spark plugs, see if one of them is wet, you may just have a leaking head gasket that needs to be replaced. Since you have to take the head off to replace it, normally I would say get the head checked at a local machine shop, but since you have one that is known to crack, its worth the money you would have spent at the machine shop to just go ahead and replace it.

extrashaky

Having shared the 0331 head crack experience, I totally understand how it can give you a negative outlook on life. But that fades with time.

(Or, in my case, it fades with acceleration and torque, since I just used the head crack as an excuse to swap in a 4.6L stroker. Lemons? Lemonade.)

Klutch

Nice! I really need my XJ to be my daily driver. So, a stroker isn't a priority right now.

Actually, other than the radiator and some overdue maintenance, my XJ is in good shape. It's very clean and has only 112,000 miles. The oil pressure appears good. I'm crossing my fingers once I install the new head, it will be a good ride.