you should probably fix the [censored] cooling system on that old vulcan, something is broken.
Running 60% water and 40% coolant for summer temps
- Thread starter mctmatt
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Originally Posted By: SuzukiGoat
I believe the difference in viscocities force the thermostat to open at a slightly cooler temperature.
That's not how cooling system thermostats work though.
They work off the principle of something called a "wax motor", meaning a sealed capsule filled with wax that has a very specific melting point and that expands as it melts.
Basically, as it melts, it pushes the thermostat open- if it's fully melted, the thermostat is fully open, and if it's fully solidified, it's fully closed.
The point of all this is that it's engineered to automatically open/close enough to keep the temperature right in the band that the thermostat is rated for, at least assuming that the engine isn't generating too much heat to do that. As a matter of fact, they typically run about half open at operating temp, to give themselves some leeway if conditions change.
So if you're sailing down the highway on a hot day, it is likely that your thermostat isn't wide open since the air blowing through the radiator is cooling your coolant enough to start to solidify that wax pellet a little bit. It's also why your engine temp doesn't fluctuate like the thermostat's a totally open/totally shut valve that merely opens completely as the engine hits the ideal temp, and shuts completely as it cools down below that temp.
So the upshot of the whole thing is that it doesn't really matter whether you're using straight water or some mix of coolant/water- your thermostat will keep that coolant right where it's supposed to be automatically, due to that wax motor action.
I believe the difference in viscocities force the thermostat to open at a slightly cooler temperature.
That's not how cooling system thermostats work though.
They work off the principle of something called a "wax motor", meaning a sealed capsule filled with wax that has a very specific melting point and that expands as it melts.
Basically, as it melts, it pushes the thermostat open- if it's fully melted, the thermostat is fully open, and if it's fully solidified, it's fully closed.
The point of all this is that it's engineered to automatically open/close enough to keep the temperature right in the band that the thermostat is rated for, at least assuming that the engine isn't generating too much heat to do that. As a matter of fact, they typically run about half open at operating temp, to give themselves some leeway if conditions change.
So if you're sailing down the highway on a hot day, it is likely that your thermostat isn't wide open since the air blowing through the radiator is cooling your coolant enough to start to solidify that wax pellet a little bit. It's also why your engine temp doesn't fluctuate like the thermostat's a totally open/totally shut valve that merely opens completely as the engine hits the ideal temp, and shuts completely as it cools down below that temp.
So the upshot of the whole thing is that it doesn't really matter whether you're using straight water or some mix of coolant/water- your thermostat will keep that coolant right where it's supposed to be automatically, due to that wax motor action.
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Just a quick update as the switch to a 40/60 ratio of coolant to water seems to be working well as we have had several upper 90 degree days with a few in the high 90's. My temperture is running around 190 to 195 per my live drive bluetooth scanner and before then it was running around 205 to as high as 215 on much cooler days. Let me be honest too and say that doing a better job of flushing might be the biggest factor.
Originally Posted By: Lubener
I doubt that your mix is making any difference. I run 50/50 and never had issues at 90+ degrees. Maybe some cooling system maintenance is in order.
Lubener , your probably right about the maintenance part and I think the flush I did this time as compared to last years is the big difference. Last year I flushed the system basically just a quick chemical flush in a few hours till ever thing ran clear then replaced the thermostate and that was it. This year I did the chemical flush for a full week which allowed it to really work its magic then flushed it all out till it ran clear. Filled it with water from the garden hose and drove it around for a good hour drive running the heater at full blast. Came back drained again then decided to do the chemical flush again just to be sure if any thing else came out and sure enough that second flush brought out even more brown stuff so I just kept doing this process over and over until the brown stopped coming out. It might be just my imagination but last year I used the Prestone Flush and this year I used Blue Devil Radiator Flush which I thought did a much better job however they may both have the exact same chemical ingrediants and plus I did allow the Blue Devil more time to work than I did the Prestone.
I doubt that your mix is making any difference. I run 50/50 and never had issues at 90+ degrees. Maybe some cooling system maintenance is in order.
Lubener , your probably right about the maintenance part and I think the flush I did this time as compared to last years is the big difference. Last year I flushed the system basically just a quick chemical flush in a few hours till ever thing ran clear then replaced the thermostate and that was it. This year I did the chemical flush for a full week which allowed it to really work its magic then flushed it all out till it ran clear. Filled it with water from the garden hose and drove it around for a good hour drive running the heater at full blast. Came back drained again then decided to do the chemical flush again just to be sure if any thing else came out and sure enough that second flush brought out even more brown stuff so I just kept doing this process over and over until the brown stopped coming out. It might be just my imagination but last year I used the Prestone Flush and this year I used Blue Devil Radiator Flush which I thought did a much better job however they may both have the exact same chemical ingrediants and plus I did allow the Blue Devil more time to work than I did the Prestone.
Originally Posted By: mctmatt
Originally Posted By: Lubener
I doubt that your mix is making any difference. I run 50/50 and never had issues at 90+ degrees. Maybe some cooling system maintenance is in order.
Lubener , your probably right about the maintenance part and I think the flush I did this time as compared to last years is the big difference. Last year I flushed the system basically just a quick chemical flush in a few hours till ever thing ran clear then replaced the thermostate and that was it. This year I did the chemical flush for a full week which allowed it to really work its magic then flushed it all out till it ran clear. Filled it with water from the garden hose and drove it around for a good hour drive running the heater at full blast. Came back drained again then decided to do the chemical flush again just to be sure if any thing else came out and sure enough that second flush brought out even more brown stuff so I just kept doing this process over and over until the brown stopped coming out. It might be just my imagination but last year I used the Prestone Flush and this year I used Blue Devil Radiator Flush which I thought did a much better job however they may both have the exact same chemical ingrediants and plus I did allow the Blue Devil more time to work than I did the Prestone.
Driving with the flush in gets a lot more out. Just don't leave the flush in forever.
Originally Posted By: Lubener
I doubt that your mix is making any difference. I run 50/50 and never had issues at 90+ degrees. Maybe some cooling system maintenance is in order.
Lubener , your probably right about the maintenance part and I think the flush I did this time as compared to last years is the big difference. Last year I flushed the system basically just a quick chemical flush in a few hours till ever thing ran clear then replaced the thermostate and that was it. This year I did the chemical flush for a full week which allowed it to really work its magic then flushed it all out till it ran clear. Filled it with water from the garden hose and drove it around for a good hour drive running the heater at full blast. Came back drained again then decided to do the chemical flush again just to be sure if any thing else came out and sure enough that second flush brought out even more brown stuff so I just kept doing this process over and over until the brown stopped coming out. It might be just my imagination but last year I used the Prestone Flush and this year I used Blue Devil Radiator Flush which I thought did a much better job however they may both have the exact same chemical ingrediants and plus I did allow the Blue Devil more time to work than I did the Prestone.
Driving with the flush in gets a lot more out. Just don't leave the flush in forever.
That;s odd, when I had my old Saturn I went the opposite way 60% Dexron 40% Water and afterwards I noted thatduring hot weather in stop & go traffic the Temp gauge didn't climb as fast, the Fan engaged less often and the engine generally ran a bit smoother in hot weather / stop & go conditions.
Perhaps it was performing the drain & flush itself which was responsible for the improvement but the extra coolant certainly didn't seem to hurt anything.
Perhaps it was performing the drain & flush itself which was responsible for the improvement but the extra coolant certainly didn't seem to hurt anything.
Today was a great test for the car with two accidents on the Tollway requiring long long wait in stop and go traffic. The temp stayed perfect got to 198 but that was it . Maybe the ratio of 60% water and 40% works at least it seems to be.
I have seen at least one OEM pre-mix coolant that is 60/40. As long as your temps don't drop below -30F for extended periods you will be fine. There is sufficient additives in that 40% of coolant to keep your system protected.
Originally Posted By: mctmatt
Today was a great test for the car with two accidents on the Tollway requiring long long wait in stop and go traffic. The temp stayed perfect got to 198 but that was it . Maybe the ratio of 60% water and 40% works at least it seems to be.
So you are saying this is the normal, controlled by the thermostat temperature?
Today was a great test for the car with two accidents on the Tollway requiring long long wait in stop and go traffic. The temp stayed perfect got to 198 but that was it . Maybe the ratio of 60% water and 40% works at least it seems to be.
So you are saying this is the normal, controlled by the thermostat temperature?
Prior to this switch my scanner was seeing live temp readings of 215 and on one or two occassions it went above that during my daily commute this was when the outdoor tempts were just reaching the high 80's so I was concerned about the commute with the hotter summer months still ahead of me. kschachn the normal operating tempt for my vehicle is around 195 to 200 and Ramblejam the reason for using the old style green coolant is that is what is recommended for this car (96 Ford Taurus),I do plan on doing a drain and fill with 50/50 in October for the winter months and that just takes me a few minutes to perform.
Originally Posted By: mctmatt
Prior to this switch my scanner was seeing live temp readings of 215 and on one or two occassions it went above that during my daily commute this was when the outdoor tempts were just reaching the high 80's so I was concerned about the commute with the hotter summer months still ahead of me. kschachn the normal operating tempt for my vehicle is around 195 to 200 and Ramblejam the reason for using the old style green coolant is that is what is recommended for this car (96 Ford Taurus),I do plan on doing a drain and fill with 50/50 in October for the winter months and that just takes me a few minutes to perform.
OK so then the cooling system (as cleaned) is no longer uncontrolled and is operating within the thermostat's setpoint. That's a good thing.
As long as it's doing that the choice of coolant is going to be irrelevant. Keep using what the manufacturer recommends.
Prior to this switch my scanner was seeing live temp readings of 215 and on one or two occassions it went above that during my daily commute this was when the outdoor tempts were just reaching the high 80's so I was concerned about the commute with the hotter summer months still ahead of me. kschachn the normal operating tempt for my vehicle is around 195 to 200 and Ramblejam the reason for using the old style green coolant is that is what is recommended for this car (96 Ford Taurus),I do plan on doing a drain and fill with 50/50 in October for the winter months and that just takes me a few minutes to perform.
OK so then the cooling system (as cleaned) is no longer uncontrolled and is operating within the thermostat's setpoint. That's a good thing.
As long as it's doing that the choice of coolant is going to be irrelevant. Keep using what the manufacturer recommends.
Originally Posted By: Astro14
Water has a higher specific heat capacity than any of the glycols used in antifreeze. So, theoretically, you're improving the ability of the cooling system to transfer heat from the engine to the radiator (and thence to the air).
But as a practical matter, your engine won't run any cooler. Your cooling system temp is controlled by the thermostat and the cooling system has plenty of extra capacity, even in Texas. It was tested by Ford in Death Valley with 50/50. If your engine is running hot, then fix the mechanical problem (water pump impeller wear, radiator scale, whatever) instead of playing chemist.
Not really. Water has a higher Heat of Enthalpy. Quicker to extract heat from the engine but slower to discharge it out the radiator. The only difference is that it (water) reaches its peak temperature a tiy slower than EG. Really not worth worrying about though.
The type of fluid is immaterial. The only thing that helps is radiator surface area and/or mass air flow rate through the fins. Evenpup flow rate makes little difference proficed it is with reasonable limits. Again, it only affects time to coolant temp equilibrium.
You could ask a mechanical engineer about this but even he/she might get it wrong unless you plug variables in a program written to simulate the engine/radiator.
Water has a higher specific heat capacity than any of the glycols used in antifreeze. So, theoretically, you're improving the ability of the cooling system to transfer heat from the engine to the radiator (and thence to the air).
But as a practical matter, your engine won't run any cooler. Your cooling system temp is controlled by the thermostat and the cooling system has plenty of extra capacity, even in Texas. It was tested by Ford in Death Valley with 50/50. If your engine is running hot, then fix the mechanical problem (water pump impeller wear, radiator scale, whatever) instead of playing chemist.
Not really. Water has a higher Heat of Enthalpy. Quicker to extract heat from the engine but slower to discharge it out the radiator. The only difference is that it (water) reaches its peak temperature a tiy slower than EG. Really not worth worrying about though.
The type of fluid is immaterial. The only thing that helps is radiator surface area and/or mass air flow rate through the fins. Evenpup flow rate makes little difference proficed it is with reasonable limits. Again, it only affects time to coolant temp equilibrium.
You could ask a mechanical engineer about this but even he/she might get it wrong unless you plug variables in a program written to simulate the engine/radiator.
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Originally Posted By: Y_K
Any effect on cavitation and corrosion in the longer term?
I seriously doubt that at 40% glycol there would be a cavitation or corrosion problem. But again there is nothing to be gained using more water.
Any effect on cavitation and corrosion in the longer term?
I seriously doubt that at 40% glycol there would be a cavitation or corrosion problem. But again there is nothing to be gained using more water.
I will say that I have seen a difference with my tempts but that could be from a much better flush that I did prior to adding in the 60% water and 40% coolant. Everything is working well right now and we in Texas are getting a much needed repreive from the heat this week as the tempts have been in the high 80's with clouds and some rain. I will do a drain and fill in September going back to a more normal 50/50 mix as the old farmer's almanac is predicting a much colder winter this year.
Originally Posted By: mark pruett
(snip)
So the upshot of the whole thing is that it doesn't really matter whether you're using straight water or some mix of coolant/water- your thermostat will keep that coolant right where it's supposed to be automatically, due to that wax motor action.
Great, some know-it-all on the internet just told me to use straight water. Thanks Mark!
(snip)
So the upshot of the whole thing is that it doesn't really matter whether you're using straight water or some mix of coolant/water- your thermostat will keep that coolant right where it's supposed to be automatically, due to that wax motor action.
Great, some know-it-all on the internet just told me to use straight water. Thanks Mark!
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