Jkhub18

The fan on engine is extremely loud. Have recently replaced all heater hoses, thermostat, radiator hoses, radiator cap and all intake gaskets. It was overheating and this is the reason for changing all that. Engine does not overheat it gets up to max of 230 the fan will come on and stay on from about 5 minutes after start up and stays on until engine is off. Its on full blast can hear over radio and not a chance of talking to anyone outside. I need help

Sixty4x4

Sounds like the AC pressure switch is not connected or plugged in correctly. Disconnected it will make the fan run full blast constantly.

Jkhub18

Thank you. I will check it later on and let you know

Mark Doiron

Sixty4X4 is probably right, but I always have to ask: Do you have anything reducing the flow of air through the grille? The US flag seems to be popular, but there are also decorative plastic mesh screens or even replacement grilles (squinting eyes), excessive or oversized lights, etc. I ask because a friend and I did some testing when we were preparing to drive into the Arctic with our Jeeps because his 2012 had the same symptoms as yours: Jeep would run up to 230-240° quickly even in cooler temps in WA state, then fan would remain in high mode until he stopped driving. It happened immediately after he installed one of those squinty eye thingies that had some meshwork in the smaller openings than stock. Our testing revealed a 10-20° temperature rise because of that new grille. We did find that there are (rather pricey) thin mesh metal inserts to provide protection from rocks that have insignificant affect on vehicle coolant temp. Personally, I was glad to see him remove that squinty eye thing because I hated to think that ugly thing would have been in all of our photos and videos from the trip.

Jkhub18

Ok so I checked and all is plugged in good. Has the factory grill in it. Checked to see if anything stopped the radiator area up and it was clean. Double checked with garden hose to see if any mud came out and nothing. Sensors reading like they are supposed to. They seem to match the engine temp. Using infrared thermometer to check temp. Also having a problem now with transmission shifting late. Kinda have to lift for it to shift. I'm lost

medicjwilson

Pentastar motor is super hard to get all of the air out of the cooling system when you open it . The bleed process is different, something along the lines of jacking up the front so it is higher than the rear and using the bleeder screw on the therm housing. Mine was overheating after service of the cooling system, large air bubble was the culprit in the end. There is a TSB on the pentastar fans as well.

Jay2013jk

This video shows how to "BURP" the cooling system after all the work you did.. Be sure that the front end is elevated some.. I had the Jscan watching and got the temp up to 205.. Yep you could see bubbles burping out during the process.

Jkhub18

Been chasing this for a while now and it has been fixed. I replaced the thermostat again and I ended up having a bad thermostat. This also fixed another problem we were having with it holding the shifts out to long.

Mark Doiron

Good deal and thank you very much for closing the loop.

Sixty4x4

On a related subject my son (who has the 2016 test bed JKUR) is going to buy the 2 x HPT credits to access the ECU and we are going to lower his temp down to 195F. Assuming a thermostat can be purchased. This will eliminate that nuisance temp alarm he gets in the summer on offroad and 95F temps outside. That is a bad design on FCA Jeep's part. Not sure how our Jeep brothers/sisters fare down in AZ, TX, CA etc in the summer. When this is done we will report back.