Not necessarily. An air bubble in the system will also keep heated water out of the heater core. Shutting off water to the heater core will not cause overheating. The OP had recent work done on his cooling system which increases the likelihood that there is air in the cooling system.
Overheating
- Thread starter Electric Banana
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- 3.6 overheat overheat
Not necessarily. An air bubble in the system will also keep heated water out of the heater core. Shutting off water to the heater core will not cause overheating. The OP had recent work done on his cooling system which increases the likelihood that there is air in the cooling system.
I don't think the heater core is blocked. I will get heat in the cabin until it runs hot, then no heat. This is driving, when sitting the temp will slowly return to operating temperature and heat will return. I'm going to drain the system, change the thermostat and start with fresh coolant. I'll get the front end up with ramps and possibly get the spill proof funnel to get the fluid even higher.
I've read a few other how to things about flushing the system. I found that on my radiator I had to unsrew the plug all the way until it came out. A couple of YT videos state(show) turning the plug 180 and pulling out a little and the fluid starts to flow out the drain tube.
Thats a great clue. U are telling us that the heater works fine when the cooling system is working. That means the heater core is OK, and its not full of air. U also say when it running hot, you get no heat from the heater. If this is true, it sounds like it over heating because the coolant has stopped flowing. How can that be the case? If the T-stat sticks that could happen, the rad would not be hot. The coolant in the heater core could cool off, and the engine would be hot.
If u had a E36 BMW, I would say the impeller on the water pump could be slipping, but I think that's just a BMW thing.
If u had a E36 BMW, I would say the impeller on the water pump could be slipping, but I think that's just a BMW thing.
OP….not trying to be a jerk but I’ve asked a few other questions several posts back you still haven’t answered about your cooling system. We are trying to help you diagnose your system to help fix it and to keep you from throwing parts at it.
I think
I thought I had answered all your questions. List them all and I will give you answers I have found. I can only work on it when I have the time after work. This weekend I'm diving in completely.
I thought I had answered all your questions. List them all and I will give you answers I have found. I can only work on it when I have the time after work. This weekend I'm diving in completely.
UPDATE: Rplace the thermostat with Jeep OEM. Spent 2 hours burping with the nose in the air. Now 5 days at normal temperature. Bad thermostat and large air bubble.
Thanks for closing the loop on this. Hopefully you don't experience any additional issues!
Afternoon once again. Here's the scoop. After replacing the thermostat, radiator cap, and multiple burping I thought the overheating was beat. I the last week I have found that the Electric Lemon has started to run a little warm. The temp will rise near 240 and then drop to normal (210) and the repeat. Still not a blown head gasket. Checked and did not find any air in the system. I have found that the cooling fan is now runnng at full speed. I've checked for codes and only finding a code for possible bad gas cap. Now my question is, Can a bad coolant temp sensor be causing the fan speed and the continuous fluctuation in the water temps? Heater is working fine.
Maybe on the coolant temp sensor. Put a new one in it and see.
What outside temps are you now running in? It’s crazy but 240 is the upper end of where the 3.6 will run under normal conditions.
Turn on the AC on low (your AC works right?) and drive around. Does your temps run lower and more stable? Turning the AC on forces the fan to come on.
Get JScan and the proper adapter to work with your phone. Use JScan to turn the fan on. Does the temp fall and stay low?
Get a laser thermometer (as already recommended) and check the upper and lower portions of the radiator. Is there a big difference in temps? What is the difference? The JK radiator having the return to the engine where it is does encourage deposits to drop to the bottom of the radiator which eventually leads to clogging of the radiator if you neglect your cooling system. Good chance on the earlier models of the 3.6 but lower chance on later models unless someone has mixed coolants.
What outside temps are you now running in? It’s crazy but 240 is the upper end of where the 3.6 will run under normal conditions.
Turn on the AC on low (your AC works right?) and drive around. Does your temps run lower and more stable? Turning the AC on forces the fan to come on.
Get JScan and the proper adapter to work with your phone. Use JScan to turn the fan on. Does the temp fall and stay low?
Get a laser thermometer (as already recommended) and check the upper and lower portions of the radiator. Is there a big difference in temps? What is the difference? The JK radiator having the return to the engine where it is does encourage deposits to drop to the bottom of the radiator which eventually leads to clogging of the radiator if you neglect your cooling system. Good chance on the earlier models of the 3.6 but lower chance on later models unless someone has mixed coolants.
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Drove to work this morning with AC on, about 35 minute drive on interstate with cruise se at 64. The temp read out ran to 242 three times during trip an but didn't stay there. ran up and then dropped to lowest reading of 208 but climbed back to 214 to 222 for trip. At half way turned off AC and turned up heater and temp didn't climb but stay around 220. All readings are from digital temp readings from dash, I tried to keep track of a cycle going from normal to hot and then back to normal. It did cycle twice in the 33 minute trip. Ran up to 242 for 2 minutes and then back down for 10 minutes then back up for 2 then down again. Wgen I go home this afternoon I will use the JSCAN. Please give me a list of information that I can program the JSCAN for to get the best information to narrow down problem. Will be leaving work around 1200/1230 EDT.
Again….what is your outside temp?
Again, have you checked the actual temps with a laser thermometer at different places….particularly the top and bottom of your radiator. You can also check the temp at the thermostat and anywhere else you want to know the actual temps.
On JScan there is a setting, I think it’s under “Trail View” or something like that. You can see your actual temps and RPM while running and can turn the fan on. The fan will only come on for a few minutes each time you turn it on but it will run full blast. It will also allow you to verify the fan is actually running.
Might be worth it to replace the temp sensor. Can’t hurt. I’d only use a Mopar sensor for it. If the Mopar sensor wasn’t available, then I’d use an aftermarket. But it is available to buy so use the Mopar one.
Run the AC with the inside fan on low. Open your windows if you are hot. The reason for that is turning the AC on makes your fan come on but with it on low, it doesn’t add a lot of heat load to the engine.
Technically, anything over 250 is overheating on the 3.6 so you aren’t actually overheating.
I agree with the highlighted above. Not a Jeep, but my wife's GMC was doing the same. Fan ran constantly and even after engine shut down. I replaced everything on it like you did above based off I was in tax season and didn't have time to properly diagnose, plus I was going off what she was telling me. I rarely drive it and when I did I noticed that I started it in a climate controlled garage and before pulling out of the garage it was over heating. Drove it around the block and it would bounce, get super hot and then go to normal.
Her sensor was only $21 and fixed it right up.