I pop on the forum every now and then to receive help diagnosing issues with my cherokee. My approach has always been reactive rather than proactive. I'm not much of a car guy. I love my jeep -- my first and only vehicle, but these days I use it as means to get from point A to B. You guys are great btw

So I've reported major issues with my coolant system in the past. It's an 01 cherokee, 185k miles. Been to the shop a few times, and I've replaced parts myself, but the problems have persisted. If I had the money and the care, this probably would have been sorted at least a year ago.

For whatever reason, the problems tend to arise in the winter. About a week ago on my way to school, the jeep overheated. Nothing new. I pulled over and filled the radiator cap with water. I also took off the upper hose and filled that. That got me home. Since then, there has been some extreme belt squealing (more so than usual) whenever I run the car. The sound may also be the water pump/thermostat. It's a very high pitched sound, like a tea kettle. The engine has smelled like burnt/evaporated coolant whenever it runs (nothing new). The past few days have been the worst. In the past I've had lots of white smoke come out of the radiator. None of that this time, but the sounds, smell, and feel of the car have been more dramatic. Today I went to fill the system up with water again before I went out. And that's when the underlying problem became quite apparent. I'll attach pics but the radiator cap had a brown coating inside, and so did the upper hose. I noticed this the other day roadside as well but it was much more significant today. It felt just like oil. Though, it did come off my skin much easier than oil. I didn't see any milky coating on the engine cap. I took the car down the road and after a few minutes there was quite a pungent smell. Not the burnt coolant smell I'm used to. I would say it smelled sweet in a way, but I don't know if that's right. It was new to me, and I didn't like it, so I turned around.

I've been complaining about my coolant "leak" for a few years now. I always dismissed the idea of a blown head gasket because I never saw the milky substance, and the engine was running fine. And it did for the last 30k miles. But I believe this is the smoking gun.

how bad is it?

 

looks like rust in the cooling system a good flush is in order. it would look like a milkshake if it was a head gasket. do a flush, then flush the heater core then new thermostat and drive.

 

Ive replaced enough cooling systems to know you are not talking about anything new. Flush and clean. In all your messing with the radiator, you knocked some rust loose. The hissing may be your radiator cap. its probably water boiling off.

 

Thanks guys. I'll do a flush. But that still doesn't solve the coolant which has been disappearing for years. It was vanishing so quick that I have just been using straight water for the longest time. I only put in real coolant when temps dip below freezing.

 

It is very possible that you have a cracked cylinder head. Your head (the infamous 0331 head) came with all of the 2000-2001 XJs. It has a known casting defect between cylinders 3-4.

The #1 symptom of a cracked 0331 head is "unexplained coolant loss".

I'm not saying that is your problem. But I am saying that it sure could be. Are you aware of this issue? Search this and all Jeep forums for information and also Google it. Knowledge is power.