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how do you check coolant level when ambient temperature is 30F

2.8K views 14 replies 9 participants last post by  bluebee  
#1 ·
How do you check coolant level when ambient temperature is 30F. The correct procedure demands certain ambient temp I think it is 20*c .The dipstick sticks level varies depending on temp.

I am thinking start the engine, watch ETC when it touches 20*c , consider it right temperature for checking coolant level.
 
#6 ·
Well to get accurate level it required to be at the specified temperature. If it was plain water, going from 20C to 0C means about ~0,2L decrease in volume (That is with 12L coolant capacity, which is what the V8 has, I'm not sure about the I6). I don't have the thermal expansion coefficient for coolant and I'm too lazy to google it, but it should be in the same neighborhood. The bottom line is, if your a bit low on coolant when checking it at 30F don't top it up, because you'll have too much coolant.
 
#8 ·
I always run mine a bit low, the stick 3/4" below the top.
Less pressure build up in the system.
Been doing this for 3-4 years with no issues, just a lower pressure reading in the gauge I installed in the radiator.
 
#13 ·
pressure gauge in cooling system



I'm not sure I see the value in a pressure gauge on the cooling system unless one want's to monitor/detect a faulty radiator cap, aka pressure relief valve. A flowmeter might make more sense.....detect that coolant fluid flow and monitor the water pump's performance; but this is a more expensive and bit more complex an install than a pressure gauge ;)
 
#14 ·
I'm not sure I see the value in a pressure gauge on the cooling system unless one want's to monitor/detect a faulty radiator cap, aka pressure relief valve. A flowmeter might make more sense.....detect that coolant fluid flow and monitor the water pump's performance; but this is a more expensive and bit more complex an install than a pressure gauge ;)
Pressure gauge is for more personal reasons. I just want to know how and where he installed it. Thanks. What some see value in others may not..
 
#15 ·
JimLev posted pressure gauge readings in this thread...
- How to modify the cooling system expansion tank 2 bar cap to 1.2 bar to vent at a lower pressure (1)
See also:
- What is the proper coolant level bobber stick height (1)
And ...
- How the expansion tank works (1)