discussion about temperatures

deQuincey

deQuincey

Quousque tandem...?
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BIO @ 43°15'46.5"N 2°56'03.7"W
in my 3.0 CS zenith carbs, stock

70% of the time my temp. reading is this:




today, sunny, 14 ºC outside temp, warm engine after 30 min drive, flat road, 3rd gear and around 3000 rpms, gauge shows water temp between three and four (apologies for this blurred pic)

external gauges will read with more precission: 89ºC for water and same for oil temps







variations to this that i have experienced are:

uphill for more than 5 minutes, 3rd gear, 5600 rpms = Water temp 95ºC
downhill for more than 5 minutes, 4th gear, 4000 rpms = wáter temp 82ºC
highway, 4th gear 6000 rpms = wáter 85ºC but oil temp 95ºC
city trafic wáter temp 90ºC

your comments ? what about your engines ?
 
Athena runs at about 4 o'clock on her temp gauge. Have a triple core radiator which keeps her nice and cool in all temperatures. Can just barely see the needle because of the glare in the pic.
 

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Seems to me your thermostat is working just fine. Varying a few degrees around the middle of the white zone, perfect. Unfortunately my temp hangs at 4:30 all the time. I think my thermostat needs to be replaced but I just haven't got around to it yet...
 
I think temps shown are not cause for concern. The most efficient coolant temp for internal combustion engines seemed quite high when I first read it... something like 85 degrees C. Thermostat controlled, which means the cooling system is held "in check" to keep the temp at that level.

What is more important is that you cooling system, whatever it is, has the reserve capacity to extract more heat above that. If you're running at 85 C but with no reserve, you're in trouble should the slightest thing happen. But with reserve, pedal to the metal!
 
pictures to show what happens when downhill for more than 5 minutes:





and the whole picture:

batt is correctly being charged, wáter temp 82ºC, oil temp 90ºC (oil needs more time to change), pressure 3bar (i recall 3000 rpms)

 
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deQuincey said:
pictures to show what happens when downhill for more than 5 minutes:





and the whole picture:

batt is correctly being charged, wáter temp 82ºC, oil temp 90ºC (oil needs more time to change), pressure 3bar (i recall 3000 rpms)

Click to expand...
Bit of thread swerve, sorry. What do the toggle switches and the green warning light do?
 
I have a fresh 80* thermostat, a new radiator with shroud, and a 9 blade fan on a viscous clutch. Mine does the same. 3 o'clock during normal operation and never any higher, and 4 o'clock down long hills at higher speeds.
 
thermostat.gif


A thermostat is not an exact device.

The Fulvia thermostat is of the wax pellet type. The wax melts at 83°C. Because the wax expands quickly and strongly when it changes phase from solid to liquid, it opens quickly between 83° and 93°. Between 70° and 83° it opens slowly due to thermal expansion of the solid wax. Over 93° it continues to open the last bit due to thermal expansion of the liquid wax. The thermostat has an hysteresis of about 2 to 3 degrees, which means the temperature has to drop 2 to 3 degrees before the thermostat starts to close. If the thermostat ever overheats, it is advisable to replace it as it may be internally damaged.

http://www.viva-lancia.com/fulvia/qanda/engine/thermostat.php
 
Mike Goble said:
thermostat.gif


A thermostat is not an exact device.

The Fulvia thermostat is of the wax pellet type. The wax melts at 83°C. Because the wax expands quickly and strongly when it changes phase from solid to liquid, it opens quickly between 83° and 93°. Between 70° and 83° it opens slowly due to thermal expansion of the solid wax. Over 93° it continues to open the last bit due to thermal expansion of the liquid wax. The thermostat has an hysteresis of about 2 to 3 degrees, which means the temperature has to drop 2 to 3 degrees before the thermostat starts to close. If the thermostat ever overheats, it is advisable to replace it as it may be internally damaged.

http://www.viva-lancia.com/fulvia/qanda/engine/thermostat.php
Click to expand...

excellent info, Mike, thank you

wax in the lancia's, what would be in our coupes ?
 
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