Why is the JK Overheating?? 2012 Jeep Wrangle JK

[@davevandenberg9911]

My 2014 JK was plagued with overheating during sustained engine rpm over 3200. Around 80 on the interstate or climbing a mountain pass (highway) the gauge would rapidly move to the 3/4 mark. Much more and the engine would cripple itself. All of the things you cover were checked multiple times. After an unrelated engine replacement, a competition radiator, and removal of the (tall) 8274 winch, the temp would still climb. One more trip to the dealer resulted in a simple thermostat replacement which solved the problem. Since the same dealer had replaced the thermostat multiple times, and was somewhat mum about how this could have fixed it, I believe Jeep had a design/manufacturing issue that persisted for over a decade. From my research, the most plausible suspect is a plastic thermostat housing that deforms when hot and prevents proper opening and closing.

[@sgtdukeM109rider]

I had an overheating issue with my 2016 JKU ended up being a head gasket. The head gasket was over stress due to the fact that one of my exhaust lobes on the exhaust cam had completely worn down when the rocker arm failed not allowing both exhaust valves to open during the cycle. It caused exhaust to back through the cooling system causing the reserve to overflow. Prior that replaced thermostat housing radiator cap hoses and water pump to no avail. After letting the vehicle cool down I would open the radiator cap and found it low, when draining the coolant I found it had an exhaust smell. At no time did I find coolant on the floor of my garage I suspect it would only leak out while the engine was hot and running and once enough exhaust gas displaced the coolant in the radiator it would cause the reserve to overflow while driving. Just a thought :-)

[@gustavogarcia1084]

I'm having the same exact problem, how much did that cost you to get fixed or what route did you go? I've had a few different opinions, most of them told me to replace the whole engine and some said if done right it can be fixed. The highest estimate I had was like $8k for replacing the motor with one that had like 42k miles on it I think, some other place said almost $4k to fix the engine I currently have.

[@miopera40]

There is one known issue these 3.6 engines have related with the plastic oil filter/cooler housing. Eventually it will bite you, the plastic loose properties and gets soft on the oil filter/cooler housing base and leaks either oil or coolant, on early stages you can't see the leak but it is there if you are loosing oil or coolant or both. Check under your oil filter, if you see water or oil get the aluminum after market version. If your jeep is heating and you don't see leaks and fans are working there is a big chance that's your problem. If you get the thermostat code check that also because on mine it wasn't the thermostat but air getting into the system from the leak. You will normally get the thermostat code way before you notice the overheating.

[@ronaldbrosius7488]

Always check hose clamps. They get loose when the weather changes and tge hoses get old. All that needs is to retighten hose clamps on upper rad hose

[@JeepSolid]

Yes. Thank you

[@WmTyndale]

Nice tour through the basic possibilities. As a new owner this is much appreciated!

[@anibalbabilonia1867]

My radiator was bad on mine. Had it replaced at the dealer, now it’s working fine.

[@adidas4275]

i just replaced my radiator in my 2010... it was leaking from the plastic tank seam. I was tempted to replace it with an aluminum one but went with OE mopar again I did install the mishimoto silicon hoses... they are very nice and super tight... wont be leaking from a radiator hose any time soon

[@JeepSolid]

I’m thinking about replacing the whole system as well

[@stevenearman8891]

Absolutely correct. Check my video on the casting sand. Heater core and radiator were clogged. Jeep and the dealer when this started said I put it in there. I pray this law suit burns their ass and we can get just compensation for replacing parts.

[@ronaldbrosius7488]

Another point that he didn't comment on, is your radiator cap. A bad radiator cap will cause your vehicle to run hot.

[@n9ghtb9k5r]

I would agree, this looks like bad radiator cap causing the coolant to boil and discharge out the overflow tank

[@JeepSolid]

But the overflow was empty

[@dg98adams]

Simple pressure tester can make the leak more obvious…… if it’s the Rad or hose.

[@proverbs9103]

My JK isn't running over hot but it sure does heat up fast it takes a long time to cool off I took the engine cover off and I'm going to put a louver on it hopefully that'll fix it up

[@roccom5988]

Fantastic video my friend. Greetings from Belgium.

[@JeepSolid]

Hey! Thank you

[@bryanharger6565]

Love your video's.... been looking for months for a used wrangler 4 door. What is your opinion how many miles is too many?

[@vigilantemotors]

Bryan, have you got yourself a Jeep yet?

[@bryanharger6565]

@@vigilantemotors NOPE haven't found one yet

[@vigilantemotors]

@@bryanharger6565 Well my man I have owned 6 Jeeps now. From TJ's to JK's and JL's, 2 and 4 door. In fact my KZbin channel on here I feature them in all of my How-To mechanic video's. If you are looking at JK's you want to avoid 2012 at all costs. They had major engine issues so don't touch them. You most likely will see many '12's for sale. The 3.6 is a good motor and if someone took care of it 100k is ok to buy. Do you have any in mind? Year make and model? That would help me out a lot.

[@bryanharger6565]

@@vigilantemotors I appreciate this info, nothing specific in mind. 4 door to better fit family, something that can be used for fun on weekends and maybe errands during week if needed. Reliable be nice also, lol since not mechanically inclined at all.

[@vigilantemotors]

@@bryanharger6565 Nice, very nice. I think you will love it. Just avoid the 2012's at all costs. If you have other questions or just like these kind of videos check my channel out, I think you will like it. Hey, maybe even subscribe to it. And if you comment on any one of my videos, regardless of the topic I will always answer any question you ask.. Let me know how it goes with the Jeep hunt and I hope to see you on my KZbin page and part of the community.

[@richarddiaz8248]

Hi thank you for your knowledge and support Question is the fan supposed to come on as soon as you turn on the AC thank you

[@MikeH_41-33_LII]

Awesome video as always! Keep us posted Dale!

[@JeepSolid]

Thank you! I will

[@DiagItRight]

I've had at least 35 aftermarket motor adapter thermostats cause over heating. 3.6l and 5.7l use factory thermostat

[@ryantepley3662]

This is a great video. Thank you. Quick question, my coolant is low in the reservoir and when the fan kicks on it is obnoxiously loud. I can hear my wife coming from very far away because I can hear the fan on. Is that normal when the coolant is low. I wouldn’t think fan noise would be impacted by low coolant.

[@defender127]

It was probably your hose clamp! You shouldn’t use those universal clamps. The clamp needs to flex with the engine temperature. That’s why you need to stick with the factory “spring band” type.

[@mikezicg7422]

Nice cast

[@wheezin_mtnbkr3576]

Look, I have never had to “burp” the 3.6L JK. The successful way to get all the air out is with that thermostat bleeder. I know it seems “low”. It is easy, use a coin to open the bleeder and close it.

[@memoriasdelpasadoypresente3845]

My problem was that I did not bleed out the air in the system when I installed a new thermostat

[@Yofavv_lightskin]

Question What would cause my floor boards to soaked after a rain ?

[@Vegas_Dave]

Good stuff..Dale. Love the channel.

[@JeepSolid]

Thank you

[@elguapo7722]

My 07 jk over heats because the fan doesn't come on. The coolant temperature sensor seems to be working because it's reading the correct temperature. I checked the relay and fuse in the box and they are good. I replaced the high speed relay behind the driver headlight, still not working. My next step is to replace the fan thermostat wiring harness behind the radiator cap that goes to the fan motor. I can't get the electrical connector off near the radiator cap. I tried prying it with a screw driver but just chewed it up. I'm stuck. Is there a special trick to getting this electrical connector off?

[@p.a.gutierrez4889]

What if it is heating up, and the fan comes on quick

[@mariokampo]

All of them jks run hotter than we re used to...i have a 2015 sahara i operated between 208f to 226f on the road come rain or shine...when i offroad i see the coolant temps go up to 230 232 at times..ive replaced radiator which was leaking and tstat and still same old story...i ve no idea what else to look at everywherebi ask they day is normal behaviour

[@1unkn0wn]

Any update on this?

[@muhammedriyas3394]

2008 jeep jk wrangler sahara edition. Ovrheatting problom. Leaking radiator and watetr pump. Iam change the water pump and radiator and. Head gasket also. Stil over heatting. What the problom?

[@zachrobberts3977]

Hey same problem with mine. Exact vehicle year too. The first time it was overheating was my thermostat and I replaced that 6 months ago but now it is overheating again even after installing a new thermostat and much faster this time. Any ideas of what it could be? It leaks a little bit of coolant

[@steveduchesne4896]

Same vehicule and year ..I juste purshase my water pump and go to change it i hope i will work 😅🥰

[@davevandenberg9911]

Have the dealer install a recently manufactured thermostat. See my post dated today for my experience with this problem.

[@rushwal]

Um... what happened to the P on your grill? :D

[@briansegura7219]

Lml that’s what I was looking at too the “P” is supposed to be Lower Cased

[@oscarwinner2034]

Jeep was repainted. Paint shops don’t know Jeeps as well as we do.

[@amberarkel5236]

Lol i waa like cool popcorn coolant

[@kkp9068]

wrong coolant,should use g-o5

[@moons2662]

The weep hole in the pump will get worse as the pump in in decline.

[@al5544al]

Sometimes car overheating because the cylinders stop

[@SertEngineering]

Letter “P” on the front grill so bothering. Lol.

[@kevinhendley8524]

jeeP