Posted by: Cloverleaf76 23rd October 2012 19:32
QUOTE(Cloverleaf76 @ 23rd October 2012 19:59)
If it had water in it, the temp was not 130.
Did the expansion cap even blow? Assuming that works, and it really is quite unlikely to break, it should blow at 1.4 bar. One of the engineers on here
will do the maths and tell you what indicated temp that should happen at with a standard antifreeze mix, but it is certainly well below 130.
http://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html says that at 1.4 bar water boils at 109.32 celsius.
For a 50/50 ethylene glycol mix http://www.engineeringtoolbox.com/ethylene-glycol-d_146.html lists the 1 bar boiling point at 107.2 celsius.
Assuming (probably wrongly!) a linear response of antifreeze siolution to pressure, the boiling point of 109.32 multiplied by a factor of 1.072 would indicate that a 50/50 antifreeze mix at 1.4 bar would boil off, popping the cap, at 117.2 degrees.
And from bitter experience it makes a BIG mess, dumping approx 40percent of the coolant all over your engine bay.