Hey guys, long time lurker first time poster here.

I have a 2001 60th anniversary cherokee, straight 6 cylinder 4.0 engine. Quite a bit of backstory here because it might give some clues as to exactly what's wrong.

Had a bad coolant leak over the summer so I brought it into a shop to be looked at. According to them it was just a hose leak, which they replaced. A few weeks later I noticed that the coolant reserve tank was empty. I topped it off and it drained again within a few days. I knew nothing about the coolant system at the time so I did not even know to check the radiator cap, or look at other diagnostics; the reserve tank was my only indicator.

I couldn't determine where the leak was coming from so I stopped worrying about it tbh because the engine was cooling properly. I'm assuming there must have been something in there because it ran fine from August through October.

4-5 weeks ago I was driving and a little bit of smoke began flowing from under the hood and the engine overheated soon after. Pulled over, opened the radiator cap and it was bone dry, even though the reserve tank was full. Put some water into the cap and I was able to get home.

Installed a new water pump for good measure. Still appeared to be a leak so I only used water as coolant.

That worked well for a few weeks. A few days ago I was out and the smoke began pouring out again and I had to pull over and wait for a cool down. Limped back home with it.

My dad played with the hoses and installed a new thermostat - got it to run properly again. At this point there was very little coolant left in the system, it was mostly water. We never got around to flushing the system and putting the real stuff in.

Last night the temp was supposed to dip below freezing. My dad urged me to put the car in the garage. I didn't for some bs reason. He told me to warm it up this morning before leaving to make sure everything was ok. It was taking forever so I just left anyways. I get a few miles down the road. A little smoke was coming out of the corner of the hood. A few seconds later a massive plume pours out explosively along with some old coolant, all over the windshield. I couldn't see anything and had to slam on the brakes.

Limped it back home. The engine did not overheat surprisingly but there was a very loud metal clicking noise that sounded like it was coming from the engine block. It did that a few days ago too.

We're having it towed tomorrow. I wonder how bad I screwed it up. Should have put it in the garage...

Sorry for the novel

 

Did you see the antifreeze pouring out from somewhere or was it like it was just disappearing? If it is just disappearing you may have a cracked head your year has the crappy 0331 head on them that are know to crack with an over heat. If it was cracked and you kept running it with water in the oil and it froze you may have to rebuild you engine.

 

What were your freezing temperatures?

It needs to be extremely cold to crack an engine block, without coolant, overnight. The engine has freeze plugs which helps to prevent block cracking. Water in the oil might make a difference, but I think it would need to be well below freezing to cause any damage sitting overnight.

The 4.0L is fairly tough and can withstand high temperatures. However, water in the oil reduces engine lubrication, causing overheating, potentially damaging parts of the engine.

Did you watch the temperature gauge while driving hot? White smoke indicates a cracked head. If the head has a hairline crack, cooling then overheating potentially makes it worse.

I would check the coolant and engine oil for discolouration and how it smells.

Also for any leaks around the water pump, hoses and radiator.
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There are several tests that can be performed to test for a leaking head gasket and cracked head.

If you have coolant loss, without any coolant leaking on the ground, indicates an internal leak.

Engine oil averages a higher PSI than the cooling system and prevents coolant from entering the engine. When the engine is off water (coolant) is able to leak into the cylinders and also during an intake stroke while the engine is running. During combustion exhaust gases can be forced into the cooling system appearing as air bubbles , reducing cooling efficiency even more.

If you have this type of problem, repairs need to be made fixing any internal leaks. Both the cooling system and engine need to be flushed out.

 

"Had a bad coolant leak over the summer so I brought it into a shop to be looked at. According to them it was just a hose leak, which they replaced. A few weeks later I noticed that the coolant reserve tank was empty. I topped it off and it drained again within a few days. I knew nothing about the coolant system at the time so I did not even know to check the radiator cap, or look at other diagnostics; the reserve tank was my only indicator." ----

I don't know for sure, but I suspect your problems will be more challenging than flushing a radiator or fixing some hoses. That coolant you've been losing might be escaping out the exhaust, which means you will have to tear that engine open and fix some expensive stuff.

I hope for the best for you...

 

I don't know. I've tried many times to determine where the leak was coming from but I never came up with anything. It never actually overheated today, something seems to have blown in the radiator. It's gotten to 270 a few times and truth be told I've probably driven a total of a few miles at that temp now. Thanks.

Yeah it wasn't bad, like 25 degrees at the lowest. I now have a lot of experience with smoke coming from under the hood. It always comes from the same point and it's always white with a musty smell. There have been times, today for instance, where white smoke would form but the engine temp was normal. Thanks for the reply

Haha thanks man. It's going to a shop tomorrow. They are very reasonable but we'll see.

 

There is nothing to "blow" in the radiator. It can get clogged, and it can leak, and (rarely) even split a seam, but there is nothing that could be "blown in the radiator".


You may have trashed your engine. When the temp gauge starts climbing, you need to stop and shut off your engine NOW.



That's not likely to crack a block. You are probably okay there.


I don't think so.

If it's smoke, you are burning something. That's what smoke is.

If it's from coolant, it's not smoke. It's water vapor, commonly called "steam". (It's not actually steam, but everybody calls it that.)


Sounds like steam.


fat, sounds to me like you really need to spend some time learning more about your vehicle; how it works, how to check basic stuff. You've made some pretty basic mistakes, and they are going to cost you some green.

We all had to start somewhere. Best to recognize the need and start learning.

 

I don't think there is any reason to worry about it now, sounds like the engine was trashed after your sixth sentence. If the rest of the vehicle is in great condition it may be worthy of a motor & all new cooling system parts. If it's just a 13 year old rust bucket, it's probably better put out to pasture.

 

That's what I'm thinking too. Cracked head, head gasket failure, sounds like cylinder pressure is getting into the cooling system now and creating a geyser.
I'd round up a cooling system pressure tester to find the leak and go from there.

 

Thanks. I'll find out tomorrow I'm sure.

Wish I was more informed about proper vehicle care beforehand.

Like I said, it's a black 60th anniversary XJ. I must pass 10 cherokees a day and I have never seen another one of these in the three years I've owned it. It was in mint condition when I payed 4600 for it; I was receiving ridiculous offers for weeks after I bought it. Also have put around 2 grand into various repairs. What a shame...

 

What sometimes happens is the rad will freeze and when engine warms it can't push coolant through ice/slush. No perm damage

Learned this decades ago (the hard way)

No one on here can say they never made some kind of automotive mistake.

 

OP, sounds like you have learned several hard lessons here. Don't take a blown motor as a death sentence. It sounds as if you are a young guy. This is an excellent opportunity to really get to know your ride, and how it works. I will agree on taking it to a shop for diagnosis, as it sounds like you lack the knowledge. But here's the good part: you can learn.

Let the shop make the prognosis. When they tell you what exactly is wrong, take it back home. At the bare minimum you're gonna need a cooling system overhaul, and worst case maybe an engine rebuild. My suggestion is this:
1. Get yourself a factory service manual. NOT a Haynes or Chiltons.
2. Get a set of mechanics tools. (HF has a decent set for under $200, I have this set and it will do 95% of what you encounter)
3. Dive in and get to work.
You will get extremely intimate with your ride, be able to do it much cheaper than a shop, and learn something in the process. And, you'll have that feeling of self-worth when you fire it up and get it to run properly. Just my .02

EDIT: in the future, if you are having a problem, PARK IT, and do some noggin pokin. Patchwork fixes and good-enough-to-get-there can and will equal higher repair bills...

 

Seemingly little known fact about the Temperature gauge on the dashboard: it measures the coolant/water temperature. If the system doesn't have enough coolant to hit that sensor at the thermostat housing, then you won't get any reliable idea of how hot that engine is.

That said, heinous engine noises probably equal expensive repairs. None-the-less, we're here to help. roninofako has given you some good advice. You need to get in there and learn about this thing. Turn some wrenches, read the forums, and learn about the vehicle. You can find the service manuals in the computer based .pdf format for less than $10 with a google search. Ask some questions, get some tools, and get to work. If you're going to own a 10+ year old car, especially a $10+ year old Jeep, then you'll save yourself a lot of money by learning to do your own work.

-Scuzz

 

Thanks guys. That note about the thermometer measuring the coolant temp is significant considering what happened yesterday.

My dad has an extensive collection of tools he uses for work. I'll see what the mechanics have to say first.

 

I think you cooked the motor.

Normally when you do that you can slap a new head and headgasket on but I think you've been doing it too long.

That and the metal noise coming from the engine isn't a good thing.

Where are you located? If you're anywhere near Connecticut I have a 4.0.

 

As a newb owner of a 2000 with the same head as your 2001 I feel for you but you are on the right track, ask questions here these guys know more about your Jeep than most mechanics you will bring it to. I wouldnt even know what 0331 was without reading these forums and now thanks to these guys I keep a close eye on the temp gauge and the coolant system.