Turbo X_J

"what is going on with my jeep."

Sounds like you may have purchased a, for lack of a better term "broken" Jeep, hopefully you got a good deal on it.

Firestorm500

Brown coolant was coolant contaminated from oil.

Caused by a likely cracked head, in your case. Even if it was originally just a blown head gasket, the head has likely cracked now due to several acute overheating cycles. AND because you have the 0331 head.

The previous owner knew this. That's why they sold it.

Pray that you haven't wiped the bearings yet.

Don't drive it again until you diagnose the problem for sure. Put straight water in it for now for diagnostic purposes. (If you live in an area where it won't freeze.)

djb383

The radiator cap does nothing directly regarding cooling the motor. The water pump and radiator are the 2 primary components of the cooling system. Brown coolant doesn't happen overnight but is almost always the result of owner neglect. End the neglect and guess work before driving it again.....sounds like routine maintenance never happened or at the least is well past overdue. Fingers crossed on no cracked head.

mikesignal

X2 on the brown coolant. More than likely it was just old, original coolant. It's an '00 with 79k, so chances are the previous owner never changed it. "Hey it's only got 79k, the 13 year old coolant is still good." but in reality coolant breaks down over time.

I would also look at your oil, see if it's milky looking. Milky oil is a sign of a head problem.
If your oil does not look milky (do a google image search), I would change the thermostat and water pump, and while you have both off, flush the system.

mcd58

im going to do another coolant flush since the system over heated and coolant dosent look clean again. im going to replace my fan clutch and my thermostat this weekend. i changed my oil after the first overheating problem and it was not milky or anything wrong. so i do not think i have the 0331 head issue yet.

mikesignal

make sure you flush the engine too. and the hoses. There will be old brown gunk in both. Flush it until it's clear. otherwise you'll have to change the coolant like 4 times. Some people say to buy distilled water to flush the system with. I did that until i ran out of distilled water and it was still coming out brown. then I was frustrated and grabbed the hose. (shame on me) you can decide for yourself what you want to use to flush it out. I would also change the water pump with the thermostat. You can get a new one for about $40.
check your new radiator cap. make sure it's the right one. I think it calls for a 16 psi cap.

djb383

Why not stop guessing and replace the water pump, t-stat and rad at the same time......only need to do 1 drain/flush/refill if u replace those 3 at the same time. I promise u, u'll never get the bottom half of a 13 year old radiator clean internally (by flushing it) especially since it's been full of brown crud for a long time. Only a rad shop can thoroughly clean it after they have removed the tanks from the core and "rod" the core out. Probably cheaper to buy a new rad (+/-$100).

Firestorm500

With plastic side tanks, radiator shops generally recommend a new radiator.

Its cheaper.

Besides, an old radiator generally comes out of the vat looking like swiss cheese.

mcd58

will i need a fan clutch wrench to replace my fan clutch? i will look into replacing my water pump and radiator.

PocketsEmpty

I suggest you replace the rad like everyone else said, but the sounds of this isn't good, buddy. It sounds like the 0331 issue, or at least a blown gasket. Better start saving your pennies.

Pressure in the cooling system that's intense enough to blow it out of the reservoir tank has been a dead giveaway for me that the head gasket is blown or the head is cracked. That pressure can only come from combustion fumes. My old Ranger had all the same symptoms and the gasket was blown and the head was cracked on it.

Good luck..

djb383

No special tool is needed for anything on the cooling system. With the old radiator out, u could possibly replace the fan clutch, t-stat and water pump blindfolded (just kidding). The XJ cooling system is really easy......git 'er done.

Firestorm500

X2. I've had a couple of old Mustangs do the same thing.

Everyone but me is telling this guy to throw money at this Jeep. He needs to definitively diagnose the problem before another dollar is spent on external parts.

It's useless dancing around the issue of the 0331 head. A poster a year or so ago said that if you have one of these, it has already cracked or will crack. Virtually without exception.

I'm beginning to believe him.

I ARE EL1TE

Even before replacing the radiator, he should flush just the radiator, to see if it restricting somewhere causing the excessive pressure. You might as well exhaust all of your free options before spending $$$.

mikesignal

could a closed thermostat cause his coollant to blow out like that?....he did say his oil is not milky-if the head was bad does it have to be milky?

djb383

In reading between the lines I'm guessing this may be the OP's 1st car and is learning what can go wrong and maybe what to look for (signs of good maintenance or owner neglect) before buying their next used car. What's that old saying......once bitten, twice shy. Always a good idea to know what to look for but still not a 100% guarantee. Spending a little money on the XJ, or any 13 year old used vehicle's cooling system for that matter, is never money wasted nor is it ever a bad investment. Just about the same amount of money that buys 1 big tire will buy a complete new XJ cooling system. I'd think most folks, after only a week of XJ ownership and 1 (or was it 2) overheats, would suspect cooling system components 1st vs the head, no? Once one learns how a automotive cooling system works, and the chain reaction of problems it can cause when it doesn't work, they begin to understand that spending a little money on routine maintenance always pays off in driving dividends.

A quote from Colin Powell:

“If it ain't broke, don't fix it' is the slogan of the complacent, the arrogant or the scared. It's an excuse for inaction......."