Hi all. I apologize in advance if I am in the wrong area. I live in southeast Michigan. Our average temp right now is about 30° F. I have a 2014 2 door jeep JK with just under 70k. It was my wifes brand new, but we've got her a newer vehicle and I took the jeep. Anywho, I saw steam coming from under the hood about a week ago. I checked the coolant and saw it was low and thought, "phew, close one". Topped it off. But I noticed the radiator cap was FREEZING cold after driving for 30 minutes. I have never not had heat. Went about a month or so with thinking the heat was slightly not as hot as usual, but with having a soft top and it being cold out, I figured the heat was just making it's way to the outside. I've since changed the thermostat, radiator cap, and burped the cooling system. An hour and a half run time with the cap off to be exact, and at an incline. Upper hose is hot, lower hose is cold, I still have heat, my temp gage is at the center mark where it always is, and my digital gage reads between 203 and 217 while driving. Transmission reads about 170. I have no idea what could be going on. Some suggest needing a coolant flush, some say bad water pump. There are no signs of leaks, whatsoever. After the burp on saturday, I test drove it and had parked it on a fresh pile of snow after the drive, and had 0 drops or evidence of leaking coolant. Any thoughts help, thank you! Sorry for the long post.
Cold Radiator Cap After Driving
- Thread starter Jardner27
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- cap jeep jk radiator thermostat water pump
Two things:
- Did you use a factory thermostat, not a low temp one?
- What kind of coolant did you use?
I replaced it with a MORAD thermostat, according to surrounding auto stores, that's the brand they sell. And I used a 50/50 OAT coolant.
Oscar-Mike
JK Enthusiast
Well I never touch my rad cap if thought it's hot.
Just wondering if the fluid is flowing through.
Just wondering if the fluid is flowing through.
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I'm just trying to make sure the thermostat isn't a low temp unit. If it is and you're in a cold climate, your thermostat is basically never opening, hence the reason it's so cold.
I would look into that thermostat you installed and see what temperature it is.
I would look into that thermostat you installed and see what temperature it is.
Oscar-Mike, the cap is definitley cold to the touch. It does warm up after I park the jeep but never gets to it's hottest then either. And Chris, if my new stat is low temp, I'm still stuck wondering what happened before changing the stat. I am so confused and never heard of anything like this. Lol
Oscar-Mike
JK Enthusiast
This is the basic principle of a cooling/heating system.
With this diagram thermostat dictates the pump on how hot/cold he needs the engine to be. So you have to start with the thermostat.
With this diagram thermostat dictates the pump on how hot/cold he needs the engine to be. So you have to start with the thermostat.
Oscar-Mike
JK Enthusiast
Don't stop there unless it's fixed
next you go and look at the heater core
then you go and look at the coolant temp sensor
or just go to a jeep shop
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Hello,
I have a similar problem with my 2017 Jeep Wrangler Unlimited Sport and my wife was driving the jeep. I got a phone call saying the jeep was over heating and eventually got it home. I replaced the thermostat, water pump and radiator cap. I've burped the system at a incline and use a large funnel to ensure the coolant was at the highest point. After all that the jeep doesn't overheat and it blows hot air like it should the A/C also blows cold. The radiator cap is cold too the touch went on a 40 min drive and checked the cap and was cold not warm at all. The top radiator hose from the thermostat was hot. I opened the bleeding screw on the the thermostat and it was definitely hot coolant lol. The lower hose was kinda warm not hot but the radiator cap still cold. Was able to even remove the cap like the engine was cold, but it was at normal operation temperature. The temperature stays around 208 or 210. I went ahead and replaced the new thermostat, that I had installed was just curious and still same thing. No overheating but cold cap and I put in atleast 14 gallons of coolant and before anyone ask. Yes, I used the correct coolant that the dealership recommended for me to use. I'm at a lost of words, took it to the dealership and they was about worthless. They had it for over a week just to say nothing wrong and not sure if they even did anything. The only thing I'm thinking of doing now is to do a coolant system flush. I had also took the Jeep to the dealership for a oil leak and they replaced the engine oil cooler. One week after they installed that new oil cooler the jeep overhead. So, should I flush the coolant system or would the oil cooler be playing a part in this issue. If anything I'll take the Jeep to a different Jeep dealership and have them look at it. I rather not, which is why I'm asking and sorry for the long ass post. Just wanted to give all the information I could thanks and any input is greatly appreciated.
I have a similar problem with my 2017 Jeep Wrangler Unlimited Sport and my wife was driving the jeep. I got a phone call saying the jeep was over heating and eventually got it home. I replaced the thermostat, water pump and radiator cap. I've burped the system at a incline and use a large funnel to ensure the coolant was at the highest point. After all that the jeep doesn't overheat and it blows hot air like it should the A/C also blows cold. The radiator cap is cold too the touch went on a 40 min drive and checked the cap and was cold not warm at all. The top radiator hose from the thermostat was hot. I opened the bleeding screw on the the thermostat and it was definitely hot coolant lol. The lower hose was kinda warm not hot but the radiator cap still cold. Was able to even remove the cap like the engine was cold, but it was at normal operation temperature. The temperature stays around 208 or 210. I went ahead and replaced the new thermostat, that I had installed was just curious and still same thing. No overheating but cold cap and I put in atleast 14 gallons of coolant and before anyone ask. Yes, I used the correct coolant that the dealership recommended for me to use. I'm at a lost of words, took it to the dealership and they was about worthless. They had it for over a week just to say nothing wrong and not sure if they even did anything. The only thing I'm thinking of doing now is to do a coolant system flush. I had also took the Jeep to the dealership for a oil leak and they replaced the engine oil cooler. One week after they installed that new oil cooler the jeep overhead. So, should I flush the coolant system or would the oil cooler be playing a part in this issue. If anything I'll take the Jeep to a different Jeep dealership and have them look at it. I rather not, which is why I'm asking and sorry for the long ass post. Just wanted to give all the information I could thanks and any input is greatly appreciated.
So your saying the only problem is the cap doesn't get hot? But other than that there's no problem?