Novak Conversions Jeep Wrangler JK shifters

2014 Wrangler 3.6 Overheating

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byoung023

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I Have been through 3 thermostats, replaced the water pump, flushed it twice, and im still having an overheating issue, and im at a loss for what to do next any ideas,
Context, all flushes/bleeds done with front end lifted 6+inches, with a coolant funnel.
No heat in the cab now as well, and the temp will fluctuate from 218-245
 
Did this start with an overheating issue or was that a result of a water pump (or other part) change? I would do a combustion leak test on the coolant if you haven't already.
 
Problem started a while back at first the thermostat went, had that happen 3 times after the second i did a combustion leak test showed nothing…. Replaced the thermostat again, fixed the problem for about 4 months then recently it had a bog overheating episode had the car towed home, gonna run another leak test friday, as well as replacing coils and plugs due to the overheat, i got a misfire.
 
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Wonder if this was resolved? 🤷‍♂️

Ignorant as this sounds, something like this is whats keeping me from flushing my JK. But it's overdue by 2 years but its only at 73k miles. Still, it needs the fluid changed.
 
Could be your water pump, the internals could fail without leaking fluid, also could be your radiator cap not releasing pressure. btw, I’ve never had to burp any systems or lifting the front ends after replacing fluid , I’ve replaced thermostats, water pumps, radiators etc on many vehicles. On snow mobiles yes.
 
byoung023 said:
I Have been through 3 thermostats, replaced the water pump, flushed it twice, and im still having an overheating issue, and im at a loss for what to do next any ideas,
Context, all flushes/bleeds done with front end lifted 6+inches, with a coolant funnel.
No heat in the cab now as well, and the temp will fluctuate from 218-245
Click to expand...

Is your fan coming on, if you’re heater’s not working there could be a circulation problem at the heater core.
 
SquatchnSass said:
Could be your water pump, the internals could fail without leaking fluid, also could be your radiator cap not releasing pressure. btw, I’ve never had to burp any systems or lifting the front ends after replacing fluid , I’ve replaced thermostats, water pumps, radiators etc on many vehicles. On snow mobiles yes.
Click to expand...

Have you opened up a Jeep JK lately it's been proven it needs to be done?
 
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SquatchnSass said:
Could be your water pump, the internals could fail without leaking fluid, also could be your radiator cap not releasing pressure. btw, I’ve never had to burp any systems or lifting the front ends after replacing fluid , I’ve replaced thermostats, water pumps, radiators etc on many vehicles. On snow mobiles yes.
Click to expand...

I have replaced the thermostat, water pump, radiator cap, radiator, and all lines and flushed any possible casting sand out of the heater-core, i did a combustion leak test yesterday results are Head Gasket, my new Endoscope comes today gonna try to figure out with bank needs replacing, and if it needs heads as well lmao
 
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tJKrider said:
I would do a combustion leak test on the coolant if you haven't already.
Click to expand...
byoung023 said:
i did a combustion leak test yesterday results are Head Gasket, my new Endoscope comes today gonna try to figure out with bank needs replacing, and if it needs heads as well lmao
Click to expand...

LH (driver's) head seems to be the most problematic. You can also do a leak-down test to see if it's both sides or just one. Sometimes it can be can be difficult to get definitive results with the scope. Other times it's obvious.
 
BLACKJKU said:
Have you opened up a Jeep JK lately it's been proven it needs to be done?
Click to expand...

Yes, I changed our 2018 JKU thermostat in the parking lot of Napa auto in Burns Oregon two months ago, no burping,no lifting the front end, I did sqeaze the radiator hose a couple times. I also removed the radiator from my 98 zj last week, as well as replace the thermostat at the same time, no burping , no lifting the front end. The water is already running downhill, what’s the need to lift the front end?
 
BLACKJKU said:
Have you opened up a Jeep JK lately it's been proven it needs to be done?
Click to expand...

Yes, I changed our thermostat in the parking lot of Napa auto in Burns Oregon two months ago, no burning, no lifting the front end, I did
byoung023 said:
I have replaced the thermostat, water pump, radiator cap, radiator, and all lines and flushed any possible casting sand out of the heater-core, i did a combustion leak test yesterday results are Head Gasket, my new Endoscope comes today gonna try to figure out with bank needs replacing, and if it needs heads as well lmao
Click to expand...

that sucks, hopefully it’s the gasket and not the heads
 
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