Cooling system works too well?

[prerunner1982]

My 97 XJ... previous owner replaced the radiator, I don't why. The radiator cap would leak, replaced it and it still leaked. Put the cap off my 93 on it and it sealed up nice. Ran at the mark below the 200-210 mark...great.

Now it's winter and when it's 20* out the heater isn't as hot as it should be. Though I do have a rouge draft the air still isn't hot. Both heater hoses are hot, top hose hotter than the bottom hose as it expected. Thought the core may need to be flushed and may still do that. I also thought the blend door may be stuck half way open, but have confirmed that is not the case.

Fired up the Torq app and it shows my coolant is 185*. Now I realize it's cold outside but my other Jeep always ran at/near operating temp.

Now if the previous owner was chasing an overheating issue that was a result of low fluid as the radiator cap seemed to not seal he may have put a 180* thermostat in, I don't know.... or my cooling system works that damn good.

Ideas?

[nickyg]

Now if the previous owner was chasing an overheating issue

Did you buy your XJ from Tony?

My 96 runs 210 in the summer and a little less in the winter. I have the stock T-stat 190ish I believe. and it's down in the 30's tonight

Not a bad idea to change it out if your uncertain and give the whole thing a flush. But what do I know? I wear socks with sandals.

[4.3LXJ]

You might want to change that tstat Jon to one you know is 195

[prerunner1982]

After thinking about it this morning I also figured it may and most likely is a failed thermostat. An old S-10 Blazer my wife had many years ago had the same issue and a thermostat replacement fixed it.

Not sure why a failed tstat wasn't my first thought....

[myjeep]

if it fails in the open position the engine will not have heat from the heater core because the coolant cant absorb heat to dissapate it in the heater core, and radiator which will make the engine run cooler than normal. not good for emissions as the computer will keep dumping gas to heat up the engine till it sees optimum temp.

[autotech98]

I have a 180 in mine and she runs the same way.

Sent from my SAMSUNG-SGH-I547 using Tapatalk

[Rockfrog]

I've been running a 180 in my 2000 for about 8yrs now. Sits about the first mark before center. It will still run at full temp in the summer but does run cooler in the winter. Heater still cooks the cabin without issue. Have seen no loss in fuel economy or adverse effect. After my original head cracked I drop a 180 in and will continue to do so.

Sent from my SGH-I337M using Tapatalk

[prerunner1982]

Swapped the thermostat last night and temp is back to normal.

[Basslicks]

Swapped the thermostat last night and temp is back to normal.

[emoji106]

Stant 195* t-stat is the way to go.

Someone put a 160 in mine... probably to "keep it cooler" without getting to the root of the problem - which was the water pump. I know because I had to replace it shortly after getting it.

https://lh3.googleusercontent.com/-WEANFzObUNU/VdZpmdbqctI/AAAAAAAAQ5k/-0srcHeKRc4/s800-Ic42/20150820_085952.jpg

But then it still wasn't working at operating temps... turns out quality does matter... surprise surprise.

Mexican garbage on the left... 'Murikan goodness on the left (...right)[emoji14]atriot:
https://lh3.googleusercontent.com/-GJAsMeDP8O4/Vo8xsCq8HWI/AAAAAAAAR7s/V88nOEV_-cc/s800-Ic42/20151201_093821.jpg

Doesn't look like anything in the picture would keep the jeep from warming up to op temps, but apparently there's something. Jeep hovers around 200-220 all the time now!

[prerunner1982]

Mexican garbage on the left... 'Murikan goodness on the left :patriot:


Got it.... or do you mean your other left? :confused::D:patriot:

[Basslicks]

Got it.... or do you mean your other left? :confused::D:patriot:

D'OH! I meant on the right.... I'll fix it. :bang:

*EDIT* Nevermind... can't.

[XJ Wheeler]

D'OH! I meant on the right.... I'll fix it. :bang:

*EDIT* Nevermind... can't.
Isn't that funny how our brains do that!

I can fix it for you. Was the Mexican garbage on the right or Murikan goodness? :D

Sent via messenger pigeon. I talk, he types.

[prerunner1982]

Leave it....

But I guess if you change it, delete my reply.

[Basslicks]

Isn't that funny how our brains do that!

I can fix it for you. Was the Mexican garbage on the right or Murikan goodness? :D

Sent via messenger pigeon. I talk, he types.

haha.... Murikan goodness (stant) on the right