Hey all I’m sure it’s been asked before but didn’t see any post on the top pages. Was having issues recently with super loud fan and slight cooling issues. did thermostat and radiator cap nothing helped. About two weeks late the oil engine cooler gave way and leaked all coolant out above motor. Did the 14 cooler and ran water to test her out without wasting coolant. Still kept having issues with super loud fan and having to add to radiator everyday. Changed the water pump and put on new belt on Friday. Seemed to be ok. Tried to add coolant and do the bleeder trick saturday but snapped off screw. Yesterday put on a new thermostat bled it while re filling them hand tightened screw. Ran it like some of the forums say then added to it when tstat opened. Did that a few times. Wife said worked well today. I added a hair to the radiator before she took the girls to dance. Now the fan is super ramped up again and reservoir is full and leaking out of the reservoir. Any ideas would be greatly appreciated i I don’t Kano what else to do. Ready to throw in the towel. Thanks.

 

Sounds like the only thing you haven't changed is the radiator which is a pretty common failure on the JK's. It will often leak from the plastic end caps where the leak doesn't occur unless you're on the road.

I'm assuming if the fan is noisy it's because the engine temp is high. Where's your engine temp gauge reading and is it fluctuating after warmed up?

 

The gauge slowly goes up to the middle and stays there. Never goes higher right now Atleast that we have noticed.

 

Sounds to me like that the radiator is probably plugged up. Before replacing it, suggest checking that the coolant is a 50-50 mix and check that the cap is holding pressure by feeling a radiator hose for pressure as the engine warms up during startup.

 

That suggests boiling at too low a temperature -- Too low pressure in the system and/or too much water in the coolant mix.

 

Have you rinsed your radiator to rid it of dust after trails? Check to see if you have water condensing out the end of your tail pipe after the engine is warm.

 

The jeep isn't running hot and you don't see any leaks correct? The fan noise you hear is probably normal should, it occurs when she is idling and it would kick on to prevent over heating. As mentioned above, did you use the right mix of water and anti-freeze? You may try bleeding it again but usually this causes an over heat situation. What happens if you stop adding fluid? Does it heat up or just stop overflowing?

 

So yesterday let it idle for about an hour seemed perfect. Gauge never went higher then the middle line. On code reader coolant temp showed 102-107 temp the whole time. Fan would come on and barely run for about a minute quietly. No leaks at all. Let it sit for about 2 beers then drove it home about 2-3 miles. By the time I got home fan was ramped up high and was leaking coolant out of reservoir overflow. Temp still stayed at middle.

 

Still sounds to me like the coolant is boiling at too low a temperature, thus expelling coolant from rapid expansion. The temp is high enough to run the fan at high speed, but not abnormally high which would move the gauge toward hot. If I'm right, the cooling system pressure is too low and/or the percentage of anti-freeze is too low. Does the rad hose feel hard like there is decent pressure? Is the coolant a 50/50 mix? Is it a Mopar or aftermarket cap? I've tried stant and other aftermarket caps that don't seal well...

 

If the most common issues above aren't the problem, check for combustion gasses in the coolant (due to bad head gasket, cracked head, etc). There are kits available for this like the harbor freight version.
https://www.harborfreight.com/combus...tor-64814.html
https://www.harborfreight.com/combus...uid-56154.html