It's 105 degrees outside. Can my cooling system handle it?

Stupid related question.
How does everyone's Ambient Temp Sensor work? Mine is like 10 degrees hot almost all the time. Maybe it got relocated when the fenders were removed.
 
Yeah, if any stock cooling system can't handle at least to 110 or so I'd be pissed.

I've installed transmission coolers on vehicles that I planned on towing a lot with, but never felt the need to get an aftermarket radiator.
 
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Nightmare9 said:
Stupid related question.
How does everyone's Ambient Temp Sensor work? Mine is like 10 degrees hot almost all the time. Maybe it got relocated when the fenders were removed.
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How are you measuring ambient temp? You mean through the compass mirror that shows direction and outside temp?
 
I gave mine a good flush yesterday and put in a new thermostat. Coolant wasn’t as clean in the bucket as it looked in the radiator 😦
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I was out wheeling in the boonies on Sunday with the AC going at 110* and the needle stayed just slightly above the 210* mark. Normally it sits just below the mark. Factory system works great except my radiator is a CSF 3244 that the PO put in. I thought about switching it out for a Mopar, but I think I’m gonna be the guinea pig and see how it holds up in terms of longevity since we’re already in triple digit weather and it’s done good so far.
 
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Jamison C said:
I gave mine a good flush yesterday and put in a new thermostat. Coolant wasn’t as clean in the bucket as it looked in the radiator 😦
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Isn't that supposed to be Orange/Yellow??? I'm on Week2 of flushing my system. I should be done tomorrow. I think it is going to take a total of about 8-10 gallons of Distilled just to flush the Thermocure...
 
This is my first summer since buying the LJ and all has been good here in Tucson on these hot days . I'm thinking about buying a Mopar radiator just to have around, but I'm not sure if I want to put the money up right now if it's just going to sit around for who knows how long.
 
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Nightmare9 said:
Isn't that supposed to be Orange/Yellow??? I'm on Week2 of flushing my system. I should be done tomorrow. I think it is going to take a total of about 8-10 gallons of Distilled just to flush the Thermocure...
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I use Gerex G-05 HOAT coolant which is actually almost clear in color. The coolant that was in the radiator was green and I could just barely see through it. What came out of the block was nasty.

This was my last jeep about 30k miles after a flush with G-05. There was crud stuck to the inside but the actual coolant was still running clear.
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It took me about ten gallons to do the flush.
 
Nightmare9 said:
Yeah, in mirror display.
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Oh, yeah I'll have to pay attention to mine and see how accurate it is. From the factory they are mounted right behind the grille in front of the radiator, which seems like a silly place to mount it if you ask me.
 
The needle basically has 5 positions when you get up to temp. Just left of 210, 210, just right of 210, about halfway between 210 and 260, and 260. This is for my 2001, I believe it changed slightly in other years.

Just right of 210 can mean anything from ~215 to ~235-240. It is best to check your real temps with an OBDII since the gauge is pretty garbage.

My Jeep spends most of its life pegged on 210 while it fluctuates from ~200-208 driving around town according to the OBD. Once I hit the highway on a 80+ degree day with AC on, it’ll move up to just right of 210 and run at 215-225.

I’ve been trying to nail my cooling system down for a while. I’d be interested to hear what the Arizona guys are running for real temps according to the OBD while idling with AC on and driving at highway speeds with the AC on. I think those numbers would be able to show what temp a proper functioning TJ should run at when under load.
 
Chris said:
Oh, yeah I'll have to pay attention to mine and see how accurate it is. From the factory they are mounted right behind the grille in front of the radiator, which seems like a silly place to mount it if you ask me.
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Mine always seems to be within 1 or 2 degrees of what the National Weather Service is reporting.
 
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Chris said:
Oh, yeah I'll have to pay attention to mine and see how accurate it is. From the factory they are mounted right behind the grille in front of the radiator, which seems like a silly place to mount it if you ask me.
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It gives a higher temperature reading initially when the Jeep has been parked in the sun but it's actually pretty accurate once you start moving and ambient temperature air is flowing over it.
 
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Jerry Bransford said:
Not normal and definitely fixable. Is there an aftermarket radiator installed?
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It’s a Mopar radiator installed either last summer or the summer before. Either way it’s got probably 10k miles on it now

Edit just for clarity, my entire cooling system is original from the factory. Aside from the Mopar radiator mentioned above and the upper/lower hoses.

I am sure what my Jeep could really use is an entire refresh, with a Mopar pump. To go along with that a good flush which I never did. Green coolant is currently being used. All those were on the list but the time and money were hard to find and I never got around to it. Looking forward to doing it this summer. Maybe fix my HVAC controls too so I can use my AC..
 
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So I went ahead and hooked up my scanner today. When I did my flush the other day I also changed my thermostat. The needle sat right below the tick so I figured while I had everything apart I’d check the thermostat. Interestingly enough, it was a 195* unit, but I went ahead and swapped it anyways since I was in there.

Cue today after driving it around for a bit and then sitting in a parking lot with the AC going. I decided to hook up the scanner since the needle is still sitting in the same place. We’re at 101* outside today.
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After giving it a few good revs I could only get it up to 206*. Just thought I’d share my findings and also help reiterate with @CodaMan that the factory cooling system is more than capable when properly maintained.
 
Jamison C said:
So I went ahead and hooked up my scanner today. When I did my flush the other day I also changed my thermostat. The needle sat right below the tick so I figured while I had everything apart I’d check the thermostat. Interestingly enough, it was a 195* unit, but I went ahead and swapped it anyways since I was in there.

Cue today after driving it around for a bit and then sitting in a parking lot with the AC going. I decided to hook up the scanner since the needle is still sitting in the same place. We’re at 101* outside today.
View attachment 171898View attachment 171899

After giving it a few good revs I could only get it up to 206*. Just thought I’d share my findings and also help reiterate with @CodaMan that the factory cooling system is more than capable when properly maintained.
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Good to see! In the hour and a half when I last posted I managed to order a Mopar pump, tstat, cap, and fan clutch (along with some other unnecessary stuff not Jeep related.. kinda bored after work these days). Hoping to have the same results.
 
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