awg

does that flow more CFM than the original ?

They would be inexpensive from the wrecker, and that way the tabs slip right into the slots in the radiator

A PO has made a slight cutout in the OEM shroud at the bottom, and that means you can slide the OEM unit in & out easily...a bonus if you do a lot of work on the vehicle
My current XJ, never has shown high engine temp symptoms, and its hot here, the AW4 is far more worrisome

ROADKILLJEEPXJ

I would not recommend drilling a hole. If the thermostat needed a bleed hole the manufacturer would sell it that way.seen someone mention that somewhere in the thread

Phydeaux33

If one buys the Mopar thermostat it does have a weep hole, only aftermarket ones don't.

awg

No hole means you cannot bleed the system till the thermostat opens, adding greatly to any potential difficulty. I drilled one, less than 1/8"

Phydeaux33

If you do drill the bleed hole make sure it is at 12 O'clock when you install.

IJM

Same with one that already comes with one. It's not going to do much when it's on the bottom.

ROADKILLJEEPXJ

Dola52 I whole heartedly believe that the a/c fan is your confirmed fix. If you are missing the shroud the goes around the mechanical fan I’d go on ahead and order one of those as well. I hooked my Jeep up to my scan tool over the weekend after installing a new A/C fan to watch my temps and noticed the vehicle stays nice and cool moving down the road but idle the vehicle overheats.

That prompted me to order the shroud and once I did that it’s perfect now. It hasn’t once over heated on me I’ve put 300 miles on it after all my repairs just to be sure. I’ll try to leave a picture of the shroud I’ve ordered. How’s your Jeep doing anyway? Have you fixed your cooling issue?

dola52

I drilled a hole in the aftermarket thermostat, 1 of 2 that I purchased ruling out a faulty thermostat, and problem seems to be fixed. Stayed at perfect temp on 200 mile road trip, and prolonged idling, (30 min). So I recommend either buying thermostat with weep hole, or drilling one before you install it. Thanks for all the advice.

dola52

​​​​​All the basic cooling components were the first things I checked. All my fans are working properly, and all fan shrouds are in place. I don't believe a faulty fan or shroud would cause the type of problem I was having anyways. The engine would be at perfect temp, then instantly spike, then after a while would instantly drop back to proper temp. I believe any problem with airflow would cause a more gradual increase and decrease in temp. I ended up drilling a weep while in the thermostat and problem solved. I guess an air pocket would form in the thermostat housing and had now where to go while the thermostat was closed. So thermostat would close, air pocket would develop exposing the sensor to hot air, sensor would detect a sudden increase in temp, then when the thermostat opened, the air pocket would get pushed along the system, and the sensor would detect a sudden decrease in temp. The weep hole allows the air to move on, preventing a pocket from developing. I don't think the engine was actually overheating, as there were no other signs of it, just the sensor was getting exposed to the air pocket making it give a faulty reading.