engine temp at 210?
#16
10-29-2009, 05:12 AM
Lead Driver
Thanks BigSix, that's exactly what I was trying to explain.
If the engine relied on the radiator to regulate the temperature, there will be no room for increased heat output and the engine will eventually overheat as the system temperature rises to equilibrium. The radiator should be able to reject a lot more heat than what the engine is producing (especially on an unloaded vehicle), otherwise it will overheat.
The amount of heat into the coolant from the engine depends on the work being done by the engine, the water flow rate, and the temperature delta between the metal and the water. The amount of heat rejected by the radiator is dependent on water flow rate, air flow rate, and the temperature delta between the coolant and air temperature. A larger temperature delta in either place will allow for more heat to be transferred for the same flow rate - i.e. a 210 degree coolant temperature will reject more heat from the radiator to air at 70 degrees than 180 coolant temp to 100 degree air. Similarly, water flow rate can be varied to alter heat rejection, which is the job of the thermostat. If the radiator is overcooling, the thermostat will close (progressively) until the outlet temperature of the engine reaches the thermostat setpoint. If the radiator is undercooling, the engine will run hotter and hotter until the temperature delta between the air and water temperature gets to the point where it can transfer enough heat.
The rated temperature is the fully open temperature. I know it's a different application, but the motorcycle engine we used for our FSAE car at school listed in the service manual that the 195 degree thermostat started opening at 176 and was fully open at 195 - I expect the same here. If it can't regulate to or very near the rated temperature, then there is something not right with the thermostat or the cooling system.
Not to sound cocky or anything, but thermodynamics was one of my best classes in mechanical engineering.
Originally Posted by Jermafenser
IT'S EITHER OPEN OR CLOSED! Like I said before: The sole purpose of the thermostat is to prevent the engine from running too cool.
WRONG. Once the thermostat hits its point, the temperature is ENTIRELY up to the radiator. A THERMOSTAT DOES NOT, AND I REPEAT, DOES NOT REGULATE ENGINE TEMPERATURE! THE RADIATOR DOES! Engine produces hot water, radiator cools the hot water down, reintroduces cool water to water pump, pumps into the hot engine. That's cooling.
WRONG. Once the thermostat hits its point, the temperature is ENTIRELY up to the radiator. A THERMOSTAT DOES NOT, AND I REPEAT, DOES NOT REGULATE ENGINE TEMPERATURE! THE RADIATOR DOES! Engine produces hot water, radiator cools the hot water down, reintroduces cool water to water pump, pumps into the hot engine. That's cooling.
The amount of heat into the coolant from the engine depends on the work being done by the engine, the water flow rate, and the temperature delta between the metal and the water. The amount of heat rejected by the radiator is dependent on water flow rate, air flow rate, and the temperature delta between the coolant and air temperature. A larger temperature delta in either place will allow for more heat to be transferred for the same flow rate - i.e. a 210 degree coolant temperature will reject more heat from the radiator to air at 70 degrees than 180 coolant temp to 100 degree air. Similarly, water flow rate can be varied to alter heat rejection, which is the job of the thermostat. If the radiator is overcooling, the thermostat will close (progressively) until the outlet temperature of the engine reaches the thermostat setpoint. If the radiator is undercooling, the engine will run hotter and hotter until the temperature delta between the air and water temperature gets to the point where it can transfer enough heat.
Originally Posted by fordman1090
The rated temp is the temp when the t-stat begins opening. You can see this if you place the t-stat in a pot with a thermometer and watch the temp rise. You will see that the t-stat beings opening slowly at 195 degrees and and continues opening as the temp of the water rises (it stops at 212 of course).
The cooling system of a trucks is all about heat transfer, thermodynamics. The t-stat is there to control that heat transfer.
The cooling system of a trucks is all about heat transfer, thermodynamics. The t-stat is there to control that heat transfer.
Not to sound cocky or anything, but thermodynamics was one of my best classes in mechanical engineering.
#17
10-29-2009, 07:05 AM
[quote=Jermafenser;8084750]Uh, what? Yes, it does. What's inside a thermostat? A wax pellet.
NO! No more that crap of yours! Seriously, where did you get that mumbo jumbo??
Once the thermostat hits its point, the wax melts thus the thermostat pops open. That's it. No more. No less. IT'S EITHER OPEN OR CLOSED! Like I said before: The sole purpose of the thermostat is to prevent the engine from running too cool.
dude. have you even put one in a pot of water and watched it? it opens little by little as the temp rises. does not matter what temp it is rated at, it does NOT just "pop" open.
NO! No more that crap of yours! Seriously, where did you get that mumbo jumbo??
Once the thermostat hits its point, the wax melts thus the thermostat pops open. That's it. No more. No less. IT'S EITHER OPEN OR CLOSED! Like I said before: The sole purpose of the thermostat is to prevent the engine from running too cool.dude. have you even put one in a pot of water and watched it? it opens little by little as the temp rises. does not matter what temp it is rated at, it does NOT just "pop" open.
#18
10-29-2009, 12:41 PM
sorry for opening up a acan of worms guys, just was hoping for a little reassurance on the temp. truck was running. i was happy with the rock steady temp of 210. i thought the t-stat was doing it's job. i put it in a pot of water before install. it stated opening at 195-198 and was fully open around 205-210. this is in a 1996-f-250 460 e4od 4x4. if that helps.
#19
10-29-2009, 12:42 PM
Postmaster
Do you know what Wikipedia is? It sure ain't an encyclopedia. It is an user-run site. Meaning, anyone can add content to whatever anyone think is correct. I don't consider Wiki a credible source.
#21
10-29-2009, 01:04 PM
You really need to settle down and watch how you talk to people. Posts filled with capital letters, calling other people's words "crap" and "mumbo jumbo" and flat-out wrong information do very little for your credibility around here.
Originally Posted by Jermafenser
WRONG. Once the thermostat hits its point, the temperature is ENTIRELY up to the radiator. A THERMOSTAT DOES NOT, AND I REPEAT, DOES NOT REGULATE ENGINE TEMPERATURE! THE RADIATOR DOES!
One more time... completely wrong.
#22
10-29-2009, 01:07 PM
ther⋅mo⋅stat
/ˈθɜrməˌstæt/ [thur-muh-stat]
–noun
1. a device, including a relay actuated by thermal conduction or convection, that functions to establish and maintain a desired temperature automatically or signals a change in temperature for manual adjustment.
ra⋅di⋅a⋅tor
/ˈreɪdiˌeɪtər/ [rey-dee-ey-ter]
–noun
3. a device constructed from thin-walled tubes and metal fins, used for cooling circulating water, as in an automobile engine.
/ˈθɜrməˌstæt/ [thur-muh-stat]
–noun
1. a device, including a relay actuated by thermal conduction or convection, that functions to establish and maintain a desired temperature automatically or signals a change in temperature for manual adjustment.
ra⋅di⋅a⋅tor
/ˈreɪdiˌeɪtər/ [rey-dee-ey-ter]
–noun
3. a device constructed from thin-walled tubes and metal fins, used for cooling circulating water, as in an automobile engine.
#23
10-29-2009, 01:37 PM
Postmaster
If the engine relied on the radiator to regulate the temperature, there will be no room for increased heat output and the engine will eventually overheat as the system temperature rises to equilibrium. The radiator should be able to reject a lot more heat than what the engine is producing (especially on an unloaded vehicle), otherwise it will overheat.
The amount of heat into the coolant from the engine depends on the work being done by the engine, the water flow rate, and the temperature delta between the metal and the water. The amount of heat rejected by the radiator is dependent on water flow rate, air flow rate, and the temperature delta between the coolant and air temperature. A larger temperature delta in either place will allow for more heat to be transferred for the same flow rate - i.e. a 210 degree coolant temperature will reject more heat from the radiator to air at 70 degrees than 180 coolant temp to 100 degree air. Similarly, water flow rate can be varied to alter heat rejection, which is the job of the thermostat. If the radiator is overcooling, the thermostat will close (progressively) until the outlet temperature of the engine reaches the thermostat setpoint. If the radiator is undercooling, the engine will run hotter and hotter until the temperature delta between the air and water temperature gets to the point where it can transfer enough heat.
The amount of heat into the coolant from the engine depends on the work being done by the engine, the water flow rate, and the temperature delta between the metal and the water. The amount of heat rejected by the radiator is dependent on water flow rate, air flow rate, and the temperature delta between the coolant and air temperature. A larger temperature delta in either place will allow for more heat to be transferred for the same flow rate - i.e. a 210 degree coolant temperature will reject more heat from the radiator to air at 70 degrees than 180 coolant temp to 100 degree air. Similarly, water flow rate can be varied to alter heat rejection, which is the job of the thermostat. If the radiator is overcooling, the thermostat will close (progressively) until the outlet temperature of the engine reaches the thermostat setpoint. If the radiator is undercooling, the engine will run hotter and hotter until the temperature delta between the air and water temperature gets to the point where it can transfer enough heat.
Once again, 180 or 195, it will reach 210 regardless. There is no point in installing a cooler thermostat period, especially on newer vehicles with onboard computers.
#24
10-29-2009, 01:46 PM
Postmaster
I believe you just contradicted yourself. Settle down there!
So far all you're doing is crying "wrong". Why don't you offer your explanation, then? Hm? Or are you frightened for your 'credibility'?
#25
10-29-2009, 01:54 PM
This forum is not really meant for arguments and name-calling, it's meant for the informative exchange of information. I'm not going to get in an argument with you over this, you clearly have a chip on your shoulder and I don't wish to be a part of it. Besides, there are far more interesting things to argue about than what a thermostat does or what a radiator does.
I reported this thread to the administrators as I believe it violates the guidelines of the site. Maybe they will be able to convince you to tone it down a notch.
I reported this thread to the administrators as I believe it violates the guidelines of the site. Maybe they will be able to convince you to tone it down a notch.
#26
10-29-2009, 04:49 PM
Lead Driver
Originally Posted by Jermafenser
Huh? How will it overheat? Get real.
I like this contradiction here:
Originally Posted by Jermafenser
When it reenters the water pump, it is too cool so the thermostat will close again until its opening point.
Originally Posted by Jermafenser
Once again, 180 or 195, it will reach 210 regardless. There is no point in installing a cooler thermostat period
Please stop trolling.
#27
10-29-2009, 04:50 PM
Dude...chill out....NOW...try being nice
... just because you have an opinion does not mean it is correct or the only way.
... just because you have an opinion does not mean it is correct or the only way.
Uh, what? Yes, it does. What's inside a thermostat? A wax pellet.
NO! No more that crap of yours! Seriously, where did you get that mumbo jumbo?? Once the thermostat hits its point, the wax melts thus the thermostat pops open. That's it. No more. No less. IT'S EITHER OPEN OR CLOSED! Like I said before: The sole purpose of the thermostat is to prevent the engine from running too cool.
WRONG. Once the thermostat hits its point, the temperature is ENTIRELY up to the radiator. A THERMOSTAT DOES NOT, AND I REPEAT, DOES NOT REGULATE ENGINE TEMPERATURE! THE RADIATOR DOES! Engine produces hot water, radiator cools the hot water down, reintroduces cool water to water pump, pumps into the hot engine. That's cooling.
NO! No more that crap of yours! Seriously, where did you get that mumbo jumbo??
Once the thermostat hits its point, the wax melts thus the thermostat pops open. That's it. No more. No less. IT'S EITHER OPEN OR CLOSED! Like I said before: The sole purpose of the thermostat is to prevent the engine from running too cool.WRONG. Once the thermostat hits its point, the temperature is ENTIRELY up to the radiator. A THERMOSTAT DOES NOT, AND I REPEAT, DOES NOT REGULATE ENGINE TEMPERATURE! THE RADIATOR DOES! Engine produces hot water, radiator cools the hot water down, reintroduces cool water to water pump, pumps into the hot engine. That's cooling.
Last edited by IB Tim; 10-29-2009 at 05:03 PM.
#28
10-29-2009, 05:06 PM
once again guys, sorry for opening up a a can of worms , just was hoping for a little reassurance on the temp that the truck was running. i was happy with the rock steady temp of 210. i thought the t-stat was doing it's job. I'm just used to other vehicles i've had running at 200 deg. i put it in a pot of water before install. it started opening at 195-198 and was fully open around 205-210. this is in a 1996-f-250 460 e4od 4x4. if that helps.
#29
10-29-2009, 05:17 PM
#30
10-29-2009, 05:21 PM
Don't worry, you did nothing wrong. I did not know there was such passion in the thermostat and radiator subculture.
