How hot is too hot?
#1
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Year: 1991
Model: Cherokee
Engine: 4.0 6cyl.
How hot is too hot?
So its been around 100 degrees here and humidity makes it feel like 115. My Jeep is running temps around 215 and not hotter than that. The ac is not on because it doesn't work and the coolant is full. The pressure cap seems to hold pressure and there is coolant flow. My question is, how warm do these 4.0L engines run normally? I am thinking about changing the T-Stat and seeing what happens. Let me know what you think. Thanks a bunch.
#6
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Year: 1996
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Engine: 4.0 upgraded
but as stated 215 is fine.
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#10
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Year: 1996
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you actual cause more damage to the engine as the engine takes longer to warm up and the most wear and tear on the engine is during warm up.
there are lots and lots of articles about it as well. never change out your tstat. always run a 195*
#11
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Year: 1992
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I hate it. but I dont think its a problem at all
x2
#12
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Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
I have 195 thermo in mine and it stays around that when I drive around town and on the open road. I had a 185 in it but i changed it when i replaced the water pump. If I'm sitting in traffic now in the heat it'll go up past 210 and come back down when I start getting cool air runnin through everything
#13
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Year: 1992
Model: Comanche
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I have 195 thermo in mine and it stays around that when I drive around town and on the open road. I had a 185 in it but i changed it when i replaced the water pump. If I'm sitting in traffic now in the heat it'll go up past 210 and come back down when I start getting cool air runnin through everything
#14
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Year: 1996
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I have 195 thermo in mine and it stays around that when I drive around town and on the open road. I had a 185 in it but i changed it when i replaced the water pump. If I'm sitting in traffic now in the heat it'll go up past 210 and come back down when I start getting cool air runnin through everything
electric fan should kick on at 218
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Year: 1999
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Verify, verify. Good data is important here.
The first thing I do with a temp question is to use an infrared point and shoot thermometer pointed directly at the thermostat of a hot engine. Then you'll know.
It is NOT uncommon to have some inaccuracy between the coolant temp sensor and the gauge.
And if you find inaccuracy, replacing that coolant temp sensor is job #1.
The e-fan comes on at about 217. If all cooling system components are working properly and you're not wheelin, you should be able to stay at 210 or lower on the 4.0
If you're not able to, something isn't keeping up. Water pump, radiator, radiator cap, fan clutch, serpentine belt that drives the water pump, thermostat.
Dollar for dollar, there is NO better money spent, than that spent on cooling system maintenance.
The first thing I do with a temp question is to use an infrared point and shoot thermometer pointed directly at the thermostat of a hot engine. Then you'll know.
It is NOT uncommon to have some inaccuracy between the coolant temp sensor and the gauge.
And if you find inaccuracy, replacing that coolant temp sensor is job #1.
The e-fan comes on at about 217. If all cooling system components are working properly and you're not wheelin, you should be able to stay at 210 or lower on the 4.0
If you're not able to, something isn't keeping up. Water pump, radiator, radiator cap, fan clutch, serpentine belt that drives the water pump, thermostat.
Dollar for dollar, there is NO better money spent, than that spent on cooling system maintenance.