My 2014 Jeep Wrangler temperature varies widely. Outside temps in the 60's. Driving 65 to 75mph temperature will be 210 to 215. When I slow down to 35 to 45mph the temperature rises to 235 to 245. If I pull over and park with motor still running the temperature will drop to 210. Speed back up to 35 to 45mph temperature will rise to 235 to 245, once I'm back at highway speeds temperature will return to 210 to 215. The fan seems to be operating correctly, I can see fan running on low and when temperature rises I hear fan switch to high. I have changed the thermostat twice, replaced the radiator. Also there is no leaks.
Overheating
- Thread starter DannyLaughlin
- Start date
Oscar-Mike
JK Enthusiast
Process of elimination:
1. Coolant Flush
2. Thermostat - done
3. Radiator fins - done
4. Hose leak - done
Item #1.
You need to replace all the coolant and blow off all the air pockets by "burping" it.
1. Coolant Flush
2. Thermostat - done
3. Radiator fins - done
4. Hose leak - done
Item #1.
You need to replace all the coolant and blow off all the air pockets by "burping" it.
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A few things come to mind:
Do that and let us know what happens
- Your coolant is too low, and therefore you have air trapped in the system.
- Your thermostat isn't functioning properly.
Do that and let us know what happens
I have flushed the system, I jack up the passenger side and bought the funnel that connects to radiator.
Oscar-Mike
JK Enthusiast
He said replaced the thermostat twice already and so I think he just needs to burp the system.A few things come to mind:
I suspect it's one of those two, but I would start with the first one, which would involve a cooling system flush (with distilled water or coolant only—DO NOT USE TAP WATER!), then putting in new coolant and burping the system.
- Your coolant is too low, and therefore you have air trapped in the system.
- Your thermostat isn't functioning properly.
Do that and let us know what happens
Oscar-Mike
JK Enthusiast
Oscar-Mike
JK Enthusiast
This is how I do mine (old school with no fancy tools):
1. Open the rad cap and see if you need to add coolant
2. If you add coolant, pour it very slow not to trap air in the rad top fins
3. Leave the cap open and then crank the engine for 5 seconds then turn it off
4. Go back and fill it again very slowly, then crank it for another 5 seconds and turn off the engine again
5. Repeat this process up until there is no more bubble coming out, until the coolant is top up to the fill rim
6. Put the cap back tight, then fill the reservoir to full, and then start the engine again, this time for longer time
7. While the engine is running, turn the heater on to max full blast high-heat, keep an eye for the temp gage as it goes up to the highest heat register
8. When the gauge is already very hot, turn the engine off, and listen for any gurgle on the engine. Let it cool down for an hour or so, then go back and open the rad cap, inspect if it needs more coolant fill
9. Repeat the process starting from #2 through #6. Before you do # 7 go and drive on the street and around the block at a full blast high-heat. This process is to shake and rock your engine while you brake and turn corners, the thermostat triggers the pump to flow more coolant into the system as the air trapped inside flows out to the rad.
As soon as you get home, go to #8, and #9 and do it all over again if you need to (engine gurgle is a sign of trapped air in there). Sorry for the long blah-blah-blah but this is my procedure.
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Dr. Vinnie Boombatz
New Member
I've noticed that the far left dash vent doesn't blow as hot as the middle and far right vents. I think i need to flush out my heater core.
Oscar-Mike this afternoon when I get home weather permitting I'll do the procedure you posted, I'll respond with results. Thank in advance.
Oscar-Mike
JK Enthusiast
I did the steps that you outlined and it seems to have helped. I haven't been on any extended drives.
Oscar-Mike
JK Enthusiast
Here are few of the signs that you succeeded:
1. When you see the reservoir level is lower than where it was
2. No more gurgling engine when you turn it off
3. Heat is blowing evenly at the registers
I just got back from a 250 mile drive. The reservoir is lower , there is no gurgling sounds and heat is blowing evenly throughout the registers.
The temp ran between 205 and 220 halfway on gauge. Towards the end of drive when doing 30 to 45mph in town driving the temp reached 245, 3/4 mark on gauge. When pulling up in driveway temp was 250. I parked but didn't turn off engine, the temp dropped to 208 at idle within two minutes and stayed there for the next ten minutes till I turned motor off. The next morning I checked coolant level, installed funnel on radiator and added roughly a quart and half of coolant. While driving I never smelt coolant and have not noticed any leaks. Could I have a blown head gasket or possibly a cracked head and the coolant is getting into the exhaust manifold and that's where to coolant is going?
Oscar-Mike
JK Enthusiast
No there is no head gasket problem and that is how the cooling system should work. But just for your peace of mind, when you stop the engine go and check the dipstick if it's milky - that is a sign of head gasket leak.
The reservoir is getting emptier because when the engine is hot (you reached 245 degrees) the thermostat kicks-in and activates the pump to flow more coolant and during this time there is expansion in the fluid, as a result the rad fluid will rise up and will kick out and blow air bubbles to the reservoir.
As a result the engine cools down because of these new fresh coolant (you said it reached down to 208 degrees) that is all good because now he is receiving and flowing fresh coolant through the cavities. The rad sucks back fluid from the reservoir as the engine cools down (fluid will decompress). That is why you see coolant disappears from the reservoir.
That is how the cooling system should work and just keep an eye on the reservoir not to get empty because if it is empty when it cycles, the rad will suck all the air back into the system and that is bad.
It's thermodynamic cycles and when it does, it gradually stabilize the cooling/heating system and this process does not happen overnight by the way because it needs a series of cycles to stabilize a process.
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Ok Jeep is still overheating. It has been at dealdealership for two days. They did a block test overnight with 30lbs on system, no pressure drop. One mechanic stood at back of jeep while the other started it. The one at the rear was checking for smoking or the smell of antifreeze coming out of tailpipe. No smoke or smell of antifreeze. They did a test on radiator to see if there was any exhaust gases in it, and found none. Still after driving roughly 45 miles it's overheating when slowing down to 35mph. When engine cools down and coolant is checked it takes close to two quarts to refill. They checked fan and it's operating correctly. They are dumb founded. Any suggestions?
Oscar-Mike
JK Enthusiast