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Old 08-06-2017, 02:32 PM   #1
mountie
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Thermostat / hot climate driving

I drive on the Gulf coast of Florida. 75% of it, is in medium traffic. not on freeway speeds

Being around 98 degrees & humid, my A/C keeps my temp around 195 to 210. No overheating, & the temp is pretty consistent.

I was wondering if I get a slightly lower thermostat if the temp would be slightly lower too? ( Or would the opening/closing at a lower temp, more often, not help?) >> fan clutch is new - BTW
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Last edited by mountie; 08-06-2017 at 09:51 PM.
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Old 08-09-2017, 07:10 PM   #2
abig84
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Re: Thermostat / hot climate driving

i put a lower one in my 1990 years ago i think it was a 180stat, as that was my thinking.

dont really know what to say, never overheated never had any issues. heat works fine in the winter
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Old 08-09-2017, 07:23 PM   #3
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Re: Thermostat / hot climate driving

If it isn't broke, don't fix it. Assuming it is stock engine, Chevy designed the engine to run with a 190 thermostat. I see to remember ChevyTech talking about some things in the computer that happen or don't happen when you have lower operating temperature. Bottom line is if isn't overheating you do not have a problem.
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Old 08-09-2017, 08:23 PM   #4
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Re: Thermostat / hot climate driving

The answer is yes, and there is no real reason to do it.
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Old 08-10-2017, 07:31 AM   #5
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Re: Thermostat / hot climate driving

I was thinking that way also.... 'but'.....

The hot 92 degree weather holds the temp at 210 with A/C.

Lowering the thermostat a tad could bring the temp back to it's 190 degrees, as per GM operating temp.

Was my thought....
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Old 08-10-2017, 07:12 PM   #6
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Re: Thermostat / hot climate driving

Not the way it works. If the thermostat is set for 190, then anything above that and the cooling system is at full flow/capacity. Putting a 160 thermostat in would just get it open sooner, then it would go to 210 eventually. You need a larger radiator. My truck never changes temp even with ac on full with 117* outside temp just sitting at a stop.
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Old 08-10-2017, 08:44 PM   #7
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Re: Thermostat / hot climate driving

Quote:
Originally Posted by Tom View Post
Not the way it works. If the thermostat is set for 190, then anything above that and the cooling system is at full flow/capacity. Putting a 160 thermostat in would just get it open sooner, then it would go to 210 eventually. You need a larger radiator. My truck never changes temp even with ac on full with 117* outside temp just sitting at a stop.
DITTO;
Heres a simple way of looking at it. If your cooling system is incapable of keeping the coolant at 195° in hot weather,, WHY would you expect it to be able of keeping it at 160° without improving how it removes heat (radiator)
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Old 08-11-2017, 08:23 PM   #8
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Re: Thermostat / hot climate driving

Have you verified you gauge is correct?
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Old 08-12-2017, 08:40 AM   #9
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Re: Thermostat / hot climate driving

Quote:
Originally Posted by Kudzupatch View Post
Have you verified you gauge is correct?
gauge works correctly.... yes
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Old 08-10-2017, 07:31 PM   #10
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Re: Thermostat / hot climate driving

Other notes, Anything blocking the front at all?
How many miles, and older multi 100k engine sometimes does run a bit harder.
What shapw is your fan shroud in?

When wash the last time the radiator and whole cooling systems was flushed?

As mentioned you will probably run just as hot with a lower temp thermostat until you find the issue
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Old 08-10-2017, 08:30 PM   #11
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Re: Thermostat / hot climate driving

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Originally Posted by Palf70Step View Post
Other notes, Anything blocking the front at all?
How many miles, and older multi 100k engine sometimes does run a bit harder.
What shapw is your fan shroud in?

When wash the last time the radiator and whole cooling systems was flushed?

As mentioned you will probably run just as hot with a lower temp thermostat until you find the issue
I kinda thought that ( lower temp 'stat')

My shroud is perfect, clutch fan new, radiator new ( standard size), cooling system fresh.... nothing blocking front.

I will get a heavy duty radiator.....
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'93 Cadillac STS Black
'93 Mercedes SL 500 Teal
'86 Yamaha FZ750 - 15,000 RPM
'86 Yamaha FJ1200 - Criminally Fast
2016 Ferrari 488 GTB, I drive it - don't own it.
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Old 08-11-2017, 10:06 PM   #12
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Re: Thermostat / hot climate driving

A lower temperature thermostat doesn't necessarily lower the temperature, since it stays in the radiator less time, cooling against the incoming air. Theres so many other factors to be considered. In liquid cooling systems, the ability to cool is determined by a number of factors, but the basic keys are the surface area of the radiator (how big/how many small fins), the air flow through the radiator (fans on/off, speed of car), and how quickly or slowly the cooling fluid goes through the radiator. If the coolant spends a small amount of time in the radiator, it loses less heat. If it spends a lot of time there, it loses far more heat. Therefore you don't want the flow to be too high as the cooling system's ability to cool the engine will be reduced, not increased.
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Old 08-12-2017, 05:37 PM   #13
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Re: Thermostat / hot climate driving

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Originally Posted by my56chevytruck View Post
A lower temperature thermostat doesn't necessarily lower the temperature, since it stays in the radiator less time,
Lost me on this one. How does a thermostat opening to full flow at X temp vs X temp change the flow rate of the water pump and system?
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-02 Suburban 4x4: leveled front
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