My cherokee has had this problem for a few months now. I changed the head gasket a few weeks ago and it barely made a difference other than fixing all the burning oil. It is fine for like half an hour, then it just starts getting carried away. It goes to 210 just fine, hangs there for a long time, but then it just starts creeping up to 220-230. I had to take my dad to the airport today in kansas city which is 80 miles or something away and being a business trip on his part I didn't need this thing overheating. I got a thermostat and water pump and changed them out, however the old ones were fine. Thermostats both opened in boiling water around the same time (new vs old) and the water pump had no cavitation at all. The belt was old and I didn't know if it was slipping so I also put a new belt on. Low and behold, same issue. This time it was slighhhhhtly better, going maybe an hour before it tipped the 215 scales. When I changed the head gasket I discovered the upper radiator hose had a bubble in it. The hose had come apart and collapsed inside the tube so it looked like you put a needle halfway into the hose rubber and blew a bubble of rubber that effectively closed off the hose. Replaced that as well. So I have all this crap and it has barely made a change. Yesterday when I dumped all the antifreeze it was kinda muddy, making me think the radiator might just be completely full of crap. My oil level is perfect after weeks have gone by from the head gasket so I doubt there is any oil/water mixing going on. I just think the radiator is completely corroded. Is there anything I can do to test this or fix this or any other ideas you guys might have? I can't see the coils in it because of the right angle plastic radiator cap housing thing. Nice thing is everything is so cheap that I could replace the whole engine for $5 it seems

If you have doubts about the radiator, Prestone makes a pretty good radiator flush. I've actually seen a few different ones they make, the stronger ones have a little more acid or whatever it is in them. I flushed a Cavalier that was all gummed up with that dexcool crap. It kept over heating and the owner couldnt afford to pay a shop to look at it. After looking over everything real well I figured it had to be from all the gunk in the radiator. I ended up flushing it twice with that stuff, each time it looked like toilet water coming out. But it did cure the overheating problem. I've also seen the lower radiator hose collapse when the tstat opens. The hose was old and deteoriated and when the system was good and hot (made the hose even softer) it would actually collapse when the stat opened, restriciting flow to the point the engine would start to over heat. It was ok at idle but when the engine was under load it gave me fits until I figured it out.

I'll have to look into that. Takes a long time to get hot and almost seems like something happens that sets it off since it can be at 210 for a longgg time, then just starts getting hot.

Take it out for a test drive. Get it hot. Now check the upper and lower hose temperatures. The lower hose should be cool to the touch if the radiator is doing its job. If not the hose will be warm or hot to the touch as well.Old california test I use to do is take a garden hose at full flow into the upper hose neck and the core tube should be capable of flowing all the flow of a garden hose without overflowing out the top or backing up out the upper neck.

I had this problem with my daughters jeep. It turned out to be a clogged cat.PM being sent.

Don't waste your time with the prestone radiator flush/cleaner. I took my radiator for the truck into a radiator shop and the guy told me that its basically soap. The EPA has had their day with the real deal stuff the radiator shops used to clean the radiators out with. He said, now its VERY few and FAR between where there are very FEW places that can still us the good stuff to clean raditors, etc.All he can do now is either re-core or replace...If I were you, take the radiator to a shop, have them look at it and see if they can tell you whats going on with it and whether or not it needs replaced/repaired, etc.If it were me, I would check to see if the water jackets in your engine are blocked. If the coolant is coming out muddy, chances are that stuff is in your block as well and you have blocked/clogged jackets. Pull some freeze plugs maybe and see what is inside...

I had this issue with my '96 XJ. I did t-stat, water pump (twice) and a coolant flush. I ended up replacing the radiator and flushing the block again. That seemed to do the trick.

Don't waste your time with the prestone radiator flush/cleaner. I took my radiator for the truck into a radiator shop and the guy told me that its basically soap. The EPA has had their day with the real deal stuff the radiator shops used to clean the radiators out with. He said, now its VERY few and FAR between where there are very FEW places that can still us the good stuff to clean raditors, etc. All he can do now is either re-core or replace... If I were you, take the radiator to a shop, have them look at it and see if they can tell you whats going on with it and whether or not it needs replaced/repaired, etc. If it were me, I would check to see if the water jackets in your engine are blocked. If the coolant is coming out muddy, chances are that stuff is in your block as well and you have blocked/clogged jackets. Pull some freeze plugs maybe and see what is inside...

So you would pull freeze plugs to "see what's inside" before you would run a bottle of cleaner through it? Not trying to be a putz but that's a lot of work! I'm not saying the stuff works magic, but if you use it as directed it does help. Theres a flush and a cleaner, the cleaner (What I used) you actually add to the system and run the engine for 5 or 6 Hours as you normally would. The cleaner has a chelating additive which breaks scale and sludge loose and suspends it in the coolant until you drain it next. It certainly wouldn't hurt to try it before taking drastic measures and tearing into an engine.

The cleaner has a chelating additive which breaks scale and sludge loose and suspends it in the coolant until you drain it next. It certainly wouldn't hurt to try it before taking drastic measures and tearing into an engine.

Just remember if the debris is plenty and big enough then it will plug the radiator core tube up and the overheat will get worse. I've had this happen with the old 1973 Dodge Charger where I drained, drop of a bottle of radiator flush, jump out in traffic in California and BAM! I was over heated in no time flat. When I did managed to get home the radiator was plugged so tight it didn't flow any water at all. So off to the radiator shop to be rodded out.

Sounds like it did it's job!

I'll definitely try all of this and see if anything comes out in the wash. I need to pull the radiator and just look in it. I think if I pull the bottom hose I can see the actual coils.

So you would pull freeze plugs to "see what's inside" before you would run a bottle of cleaner through it? Not trying to be a putz but that's a lot of work! I'm not saying the stuff works magic, but if you use it as directed it does help. Theres a flush and a cleaner, the cleaner (What I used) you actually add to the system and run the engine for 5 or 6 Hours as you normally would. The cleaner has a chelating additive which breaks scale and sludge loose and suspends it in the coolant until you drain it next. It certainly wouldn't hurt to try it before taking drastic measures and tearing into an engine.

Ugh, had a whole reply typd up to respond to this and lost it...:banghead:

I'll cut to the chase on my reply. Sodium citrate is what is in the flush. Its like using soap... There is no acid in it like the pre-epa stuff...

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I'll definitely try all of this and see if anything comes out in the wash. I need to pull the radiator and just look in it. I think if I pull the bottom hose I can see the actual coils.

Through the years of DIY'ing my mechanics, I found that small mirrors really come in handy. You can use them to reflect the light and get a good look behind something without a sweat. One mirror that I have is just like a dental mirror. I think I got it when I went in for a checkup but I think you can also get them at the store too. It would be small enough to fit into the radiator cap hole and then shine a light on it and take a peek...

Alright I know I am slow at this mainly cause I live in an apartment now and can't exactly do anything but slam the hood in the parking lot. A week or 3 ago I used my IR heat gun and was only getting 20F between the 2 radiator hoses. The radiator leaks now so I bought a million dollar one to replace it. Now I would like to clean the crap out of the engine too, would any of that radiator flush work or being I am replacing the radiator and don't care if it gets clogged, is there a more aggressive route to take or something?

Seriously I would call a local radiator shop and ask what they use to flush blocks out.

I used a CSF radiator I ordered online, worked great, good price and they are all aluminum . Just a thought. That was on a 95 Cherokee , I also used their radiators in my TJ.

I got a triple core to replace the single core piece of crap on ebay. It's all aluminum and very fancy looking. Threw it in and that thing doesn't even get to 210 now. Tops out around 205 maybe. Around town the electric fan never even comes on. That thing is just incredible. Very happy with it. I can definitely do whatever I want at this point and never have it overheat.

Now stay up with coolant changes and you'll never have to worry. Time wise I see a common 36 months or mile wise about 30-36K miles.