Losing coolant

[Justin S.]

I'm losing coolant pretty quickly. I've done some searching around and my symptoms don't seem to be the same as any of the other issues I've seen.

I have a 2000 Sport with the 4.0. Little backstory, I had a big overheating event last year. When I finally got home I was spraying cooling out the main hose. I replaced that, the thermostat, and 18psi rad cap and since then I've been able to consistently stay between 200-210. Looking under the oil cap I just have clean oil, none of the discolored build up the would suggest something wrong in the engine. I not noticing any big leaks, at least not to be the main source of losing it. The spout at the bottom of the rad on the passenger side is wet, driver side is dry. Should I just go ahead and replace all hoses to start with? Do a full flush of coolant? Water pump or rad replacement? Appreciate any help.

 

[BC Moto]

How bad was the over heating the first time? Maybe ypou have a slow leak into a cylinder have you checked the plugs?

 

[Justin S.]

How bad was the over heating the first time? Maybe ypou have a slow leak into a cylinder have you checked the plugs?

It hit the red. I was able to get it stopped and cooled down. Managed to make it home without hitting the red again. Then replaced everything before driving it. I have not checked the plugs but can do that, what do I look for?

 

[BC Moto]

The plus would be wet to the touch not oil texture, a blown head gasket shows signs of oil and water mixed but if its a minor leak in the head gasket it can leak into a cyl and burn off but there would be coolant residue/moisture on the plugs

 

[KennethS]

A few years ago I had a severe overheating issue and used a combustion gas test kit from the local auto parts store. They rent the kit and and you purchase the bottle of test fluid ($9). It was really easy to use and definitively ruled out a head gasket leak.

https://www.oreillyauto.com/detail/...s-evertough-combustion-leak-tester/ren1/67094


https://www.oreillyauto.com/detail/...98-jeep-wrangler?q=combustion+leak+test&pos=1

 

[TheBoogieman]

I'm losing coolant pretty quickly. The spout at the bottom of the rad on the passenger side is wet,

View attachment 440161

That's a good place to start before throwing money at it. My 00' was losing coolant weekly. No overheating (until the coolant was low). I had to refill the reservoir, but the radiator was never low. I drove it like that for 18 months. Plugs looked perfect, no leaks, smells, drips or coolant in the oil. I was selling it at the time and told the potential buyer. They took it to a mechanic that charged them $200 and kept it for 8 hours. Compression was normal and no issues that they could find. I knocked the price down $1500 so they could fix what I already knew was wrong. Cracked head.

 

[Justin S.]

I appreciate all the feedback. Making me nervous! I'm going to check on the spark plugs and then do that test that was recommended.

Didn't think this was related but maybe, for about a year or two I've been smelling some exhaust. I thought it was possible it was an exhaust manifold cracked but haven't found it yet. It also has the a clamp on the exhaust pipe under the passenger seat, not welded together. I've worked on that a number of times to seal that up but don't think it's that.

 

[williambmac]

How quick is quickly? how much are you adding and how often? 2000 Tj's have the 0331 casting which is prone to cracking. Especially after a bad overheat.
My wife's 2000 WJ had three-cylinder head replacements. My 00 TJ had one.
When they crack it's usually between cylinders 3 and 4, if I remember correctly. A tell tail sign is low coolant with no visible signs of leaks.
You can remove the valve cover and inspect. Here's a picture of what to look for.

 

[Justin S.]

I don't drive it but a couple days a week. After about two weeks or so the overfill tank is down towards the bottom and I fill it to the full line.

I noticed the other day a little bit of white smoke coming out of the exhaust.

 

[Cornbread]

Have you checked your heater core? Mine leaked down fairly quickly for years and I began to assume I had the cracked head as my model year was a 2000. Low and behold I had a leaky heater core that didn't show much sign of leakage for how quickly it lost its coolant.

 

[Justin S.]

I have not checked the heater core. I'll do that next.

If it's the head or the gasket, anyone have rough numbers on what that fix should cost? Also am I doing any lasting damage driving it like this? It's really just a fun vehicle for the family to roll around in. I was getting it ready to take off roading a little but now I worry about putting too much stress on that engine.

 

[Jerry Bransford]

I noticed the other day a little bit of white smoke coming out of the exhaust.

Sure it wasn't steam indicating a blown head gasket or cracked head?

 

[TheBoogieman]

I have not checked the heater core. I'll do that next.

If it's the head or the gasket, anyone have rough numbers on what that fix should cost? Also am I doing any lasting damage driving it like this? It's really just a fun vehicle for the family to roll around in. I was getting it ready to take off roading a little but now I worry about putting too much stress on that engine.

I paid $1500 for the head and labor on my 00' XJ. I always end up living in places that won't let me work on vehicles. Usually, I'll do it at night anyway.