Vladimer

Started back in November, long uphill runs in 4 lo would creep the temperature up but otherwise manageable. Then it progressed to high speed drives in 5th/6th.

Couple months ago I had the coolant flushed at the dealer to descale it and all that good stuff. Seems to be worse over all since then but the temperature has also warmed up considerably. +25 instead of -20. Most things I've found online point to replacing stuff I've done or with the auto.

At this point it is starting to climb in temp even when driving around in 2wd.

Mines a '12 with 6 speed.

I've taken out the fan and ran a hose on both sides of the rad for over an hour to clean it out, runs clear everywhere. I've replaced the thermostat and the rad cap last night and took it for a sprinted drive. The temp seemed to stay around the middle but did start climbing a bit towards the end. I'm on the trail for another 3 days so we'll see how it runs then. But any ideas what the next step might be or a way to trouble shoot whats left?

I assume the fan or the rad is not running right. The rad looks to be fine visually though, no holes/leaks/dents.

Earlier on trail runs, the most I've had it peak at was 113 degrees before I was able to stop and let the fan cool it off back to 99/100

ronjenx

If you have ever been in the mud a got some in your radiator/condenser, it won't be clean enough until you remove one of them to clean the fins between them.

If you have anything standing in front of the grill, it will disturb the air flow through the radiator. That will be most critical on the road.

Have you removed the air dam under the bumper? If so, that will reduce air flow through the radiator, unless you have replaced it with a skid plate that serves the same aerodynamic purpose.

How about the fender skirts? Still installed? If not, that will also reduce air flow through the radiator. Again, most critical on the road.

Hood vents? If they are back toward the windshield, they will be in a high pressure area when traveling on the road. Air will go into the engine bay through the vents, reducing air flow through the radiator.

The Black Jeep

113 and 99/100 is about 96/83 degrees under operating temp
Am I missing something here are we talking Celsius or Kelvin or something
???

ronjenx

Looking at the OP's location, and doing some math, I assumed the temperatures are in Celsius.
It would have been nice if the C or F had been used after the numbers, though.

The Black Jeep

Ok 113°c. Is 235°f

To the op how are you getting your temp ?
When you replaced your thermostat what did you put in ° ?

Vladimer

Oh I've gotten more mud on the Jeep then I can shake a stick at over the years. Never had an issue until recently. I removed the rad fan so I was able to put the hose right against the rad itself and wash out all of the fins. I ran each square until it ran clear. Would this not be the same as hosing it out when its outside of the Jeep?

I have two Lightforce 240's in front of the grill but haven't had issues with them on the Jeep until recently which would lead me to believe something is not working as well as it should?

The plastic air dam is removed and there is a skid plate under the e-swaybar disco.

Fender skirts are trimmed as per that TSB a long time ago but the rest of the skirts are in there and not damaged.

Only hood 'vent' is where the AEV snorkel enters into the hood, but no actual vents. It is the standard smooth OEM hood.

I'm using the torque app and streaming it via bluetooth from the obd2 port to the tablet. I have it hooked up on a ram mount so can have it open while its running.

Sorry, that is correct. Celsius. Idle is about 212F if its being used. Sometimes if it sits for awhile it will be at 201 F. It easily climbs up to 235 F where I try to slow down or stop if I got over an obstacle or hill. I think the absolute highest it has been is 239F


After replacing the thermostat I wasn't able to check it as my tablet was dead and the charger didn't want to charge it fast enough to keep it alive from 0. The OEM gauge normally doesn't move and ignores the small flucations up to 230F and once it goes over that it starts raising the needle. When I was testing it out it did start moving the needle so I can only assume it was hitting over 230F

ronjenx

There have been other threads dealing with the water temp on the 3.6L engine getting in the 230°F range, and it seems to be not an issue. That is a lot higher than the 3.8L engine normally gets.

Regarding the radiator, the only way to know for sure it's clean between it and the condenser is to remove one of them. I've seen it many times that there will be mud packed in the fins even though flushing from the grill side and engine bay side seems OK.

What you are seeing may be the cumulative effects of smaller issues taxing the cooling system. Any one of them won't be noticed, but added together, they reduce cooling capacity.

The Black Jeep

Curious what temp thermostat did you put on when you replaced the original

Spytec128

I had a temp problem and it ended up being the hose from the radiator to the bottle. It would allow hot water to go to the overflow bottle under pressure but once it started cooling off and produced a vacuum it would collapse the hose and not allow the fluid back in the radiator. It would keep my radiator from keeping water in it.