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2015 Jeep Wrangler Overheating Issue

appst8design

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First time posting to this forum but I'm at my wits end trying to diagnose an overheating issue. I've got a 3.6 JK Altitude Wrangler with 77k miles that's barfing coolant out of the radiator overflow tank. So far I've changed the coolant temperature sensor (I was getting a code, it's gone now), thermostat and radiator cap each time refilling and burping the system on a very inclined hill. I've had a leak down test performed by a mechanic and ruled out a cracked head gasket (no coolant in oil or oil in coolant). Runs great other than it overheats after it pushes all the coolant out of the system. I've also read that it's a pain the a** to get the air out of these engines but at this point with all the burping an refills I'd think this wouldn't be the case. Typically will go for a couple days after a refill leaking slightly out of the overflow before really discharging larger amounts (I assume this is because the more coolant it loses the faster it warms up and more it boils over).

Anyone have any suggestions? I was thinking maybe clogged radiator or bad water pump (I was under the impression when pumps fail it's all or nothing)? Wanted to ask before just throwing money at it.
 
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appst8design

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Is the cooling fan working correctly?

Anything blocking the cooling of the radiator?
Coolant fan comes on when ECT reads 220ish (guessing at this with OBD reader) sounds like Jeep is about to take off.

Nothing blocking front of Jeep, fins look in good condition.
 
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appst8design

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Did you use the correct coolant? If you mix coolant it will crystallize and form a goo and plug up.
I did accidentally mix different coolants awhile back but had radiator flushed day after. You think the symptoms above could be signs of a plugged or partially blocked radiator? That's one reason I was kind of leaning towards getting that replaced next.
 

mrjp

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I did accidentally mix different coolants awhile back but had radiator flushed day after. You think the symptoms above could be signs of a plugged or partially blocked radiator? That's one reason I was kind of leaning towards getting that replaced next.
Yea I would have the radiator rodded out and flush the block and heater core.