Novak Conversions Jeep Wrangler JK radiators

Engine overheating above 60 mph

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hhensl34

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Wrangler Sahara 2016. Started over heating a couple months back. A few people mentioned it could be a blown head gasket but also thermostat or water pump. We replaced the thermostat and water pump and problems resolved for awhile. Now it keeps overheating anytime we go onto the interstate above 60mph. She does fine driving city roads. Fan is also blowing really hard now to the point it’s audibly noticeable. Thermostat will go back down if we crank up the heat and drive back under 70mph. The air blowing out of the air vents when we do this is scorching hot. Any ideas? Any advice? Thank you🙏🏼
 
hhensl34 said:
Wrangler Sahara 2016. Started over heating a couple months back. A few people mentioned it could be a blown head gasket but also thermostat or water pump. We replaced the thermostat and water pump and problems resolved for awhile. Now it keeps overheating anytime we go onto the interstate above 60mph. She does fine driving city roads. Fan is also blowing really hard now to the point it’s audibly noticeable. Thermostat will go back down if we crank up the heat and drive back under 70mph. The air blowing out of the air vents when we do this is scorching hot. Any ideas? Any advice? Thank you🙏🏼
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Do you have stock tires/gears?
 
See my post I just recently did. If you replaced the thermostat, I would go after the engine coolant sensor. It was $30 and a piece of cake to replace. See this video I found to get to it without taking your fender completely off.
This will be just one more thing that you can knock out as a potential cause for super cheap. I have 37"s on my jeep.
 
I would not rule out the t-stat. Plenty of people have been through a few of them before the problem was solved. Ours went out within a year. Plus some of the aftermarket t-stats can cause problems.
 
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Your description sounds like you've still got a bad thermostat. And make sure you've elevated the nose when you're burping the coolant.

If you're concerned about the head gaskets (and if you're overheating, that's always a concern), just get a test kit from your favorite parts store and test the coolant for combustion products.

Your fan could also be an issue. If it's noisy, it could be because it's failing.
 
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Quick check if head gasket is failed, look at your oil dipstick and see if your oil has turned into a milkshake looking liquid. I agree with those guys above. Sounds like a thermostat issue. There is an airbleed valve on it that allows you to burb it (but do when it's cold though!!).
 
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Doggy-DQ said:
Quick check if head gasket is failed, look at your oil dipstick and see if your oil has turned into a milkshake looking liquid.
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That only tells you anything if the damage to the head gasket is in a place that allows coolant to enter the oil.
Doggy-DQ said:
I agree with those guys above. Sounds like a thermostat issue. There is an airbleed valve on it that allows you to burb it (but do when it's cold though!!).
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If you don't bring the engine up to operating temperature, the thermostat will not open, which means there will be no flow through parts of the system.
The best way to burp a JK is to run the front end up on ramps (or some other method that raises the nose at least 6"), remove the radiator cap, start the engine and keep topping up the fluid.
 
Novak Conversions Jeep Wrangler JK radiators
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