Coolant disappearing

[Ejforan]

So I was cleaning out the engine bay and realized the coolant reservoir looked empty. I checked and it was completely empty so I filled it back up. I drove a little bit maybe a mile or two and I checked and it definitely dropped by about an inch. This alarmed me and am wondering if it could be a blown head gasket which is not something I want to have looked into. One thing I noticed is that the lower radiator hose looks grimy and disgusting looking, or what I think is the radiator hose at least. I also checked the dip stick and the color was definitely not milky but it did smell a little sweeter than I would like. Does anyone have similar experience to this? Hasn't over heated or anything either.

 

[EzPeezy]

If you want to know for sure you'll probably need to drain the oil and see what it looks like

 

[Goatman]

Coolant can go straight to the cylinder and get "burned" with the fuel. Doesn't half to go into the oil. But if you are losing that much then you should have a cloud of white steam coming out the tailpipe. And it should smell sicky sweet too. You can pressure test the radiator. Or just warm up the Jeep and go smell the exaust.

 

[06lj]

Before assuming the worst start by checking all of your hoses and connections for leaks. Also inspect the seams on your radiator. I had a small leak on my XJ at the thermostat housing that took me a bit to chase down. If you have a uv light they sell fluorescent dye at most auto parts stores that will make small leaks easier to find.

 

[CodaMan]

You never mentioned the coolant level in the radiator. Maybe the reservoir was filling the radiator back up.

 

[06lj]

Coolant can go straight to the cylinder and get "burned" with the fuel. Doesn't half to go into the oil. But if you are losing that much then you should have a cloud of white steam coming out the tailpipe. And it should smell sicky sweet too. You can pressure test the radiator. Or just warm up the Jeep and go smell the exaust.

Another easy way to check is to smell the coolant reservoir. If it smells like exhaust you most likely are going to need a new gasket and possibly a new cylinder head. My neighbor had this happen last year. He was loosing coolant and couldn't find any leaks. One sniff of the coolant and I told him the bad news. When I pulled the head there was a very small hole next to the coolant passage right underneath the head gasket cylinder ring. It wasn't loosing much coolant so he didn't have any white smoke or moisture in the exhaust. Hopefully this is not the case.

 

[Grant Lasson]

Water pump? I've had to replace mine for the same symptoms. Hard to find the leak. Kind of appeared to be an oil seal leak because it seeped to the oil pan. Mixed with the dirt on the oil pan, wasn't obvious that it was coolant and not oil.

 

[Flivver250]

Clean the hell out the engine bay and then roll up your sleeves and look closely. Water pump, radiator, heater core, heater hoses, radiator hoses, T-Stat are all areas that should be visually inspected as a matter of course. Sometimes it can be seepage from multiple areas. Get a pressure tester and pump up the system.

 

[ranwilrw]

My resivoir has a leak in it, I can fill it to the full cold line and the next day it will be down to about 2" in it and will stay there, fill it again and the same again next day, so as long as I have that 2" I figure all is good. It has been at the 2" mark for about 3 months now, never had to add any to the radiator.

 

[Ejforan]

Update coolant burst out from somewhere.

 

[Camhabib]

Fill the system with distilled water, grab a pressure tester, and see where it’s dripping from. If it’s from the heater core you’ll see it primarily in the cabin under the passenger carpet, otherwise one of the hoses probably let go.

 

[Ejforan]

Fill the system with distilled water, grab a pressure tester, and see where it’s dripping from. If it’s from the heater core you’ll see it primarily in the cabin under the passenger carpet, otherwise one of the hoses probably let go.

I have been driving more with it and it seems fine. Hopefully it was just a release because i filled it a little too much. The reservoir is back to the full line and since I have filled it the temperature has been going up slower than it did so that is a good sign.

 

[Flivver250]

Disappearing coolant fixed itself? How and where did the system release itself other than the coolant overflow bottle? When a cooling system is not operating normally, there is generally a problem somewhere. They aren't prone to temperamental behavior for no reason.

 

[K0LCB]

Overfill? Loose radiator cap?

 

[Camhabib]

I have been driving more with it and it seems fine. Hopefully it was just a release because i filled it a little too much. The reservoir is back to the full line and since I have filled it the temperature has been going up slower than it did so that is a good sign.

There’s no way coolant should just release. It’s a closed system that only “opens” when the pressure increases above what it was designed for, aka overheats. You could have had an air pocket somewhere that was filled with fluid from the reservoir, but that seems unlikely to happen in a normally function system, and is again usually indicative of an issue. My best guess if the HVAC box isn’t leaking anything is that one of those hoses isn’t tightly clamped down and came a bit loose when you went over a bump and started spraying a bit.

 

[Goatman]

If you had coolant blow out it came from somewhere! Find that somewhere. It's a lot easier than having a blown engine. There is no place that randomly blows out coolant and then all is well. Something let go and until you find/fix it the engine is in danger. Bearings can spin while you drive down the road. Find that blow hole!

 

[mots]

Yep, grab a pressure tester and roll up the sleeves. Or take it to someone that can help you find the problem. If it’s spraying all over the engine bay like that, it should be easy to locate.

 

[Ejforan]

There’s no way coolant should just release. It’s a closed system that only “opens” when the pressure increases above what it was designed for, aka overheats. You could have had an air pocket somewhere that was filled with fluid from the reservoir, but that seems unlikely to happen in a normally function system, and is again usually indicative of an issue. My best guess if the HVAC box isn’t leaking anything is that one of those hoses isn’t tightly clamped down and came a bit loose when you went over a bump and started spraying a bit.

There is a definate chance there could have been an airpocket because I had no idea how long the coolant reservoir had been empty but I will definitely pressure check it as everyone has recommended. Thanks for all the help!