Radiaror / Engine cooling, best fan set up

[Beachy]

I have always wondered what is the point of pressurising the system is if anyone can explain it would be good does it raise the boiling point much ? ,a system I though ran under 15 psi which is not much pressure

[damienengland]

I have always wondered what is the point of pressurising the system is if anyone can explain it would be good does it raise the boiling point much ? ,a system I though ran under 15 psi which is not much pressure

Hi Beachy. Each engine manufacturer will specify the cooling system pressure required and this is most appropriate to modern engines where coolant temps can range up over 100 deg C without issue. The key is for the coolant to not boil, so pressure plus glycol is used to keep things under control. As far as pressure goes, generally its as simple as getting the correct cap for say a 308 and things should be ok. With coolant, there are two important service points. One is to ensure the 50/50 mix which can be checked instantly usuing a refractometer, the other is end of life checking which is the acidity of the coolant. Over time, the engine combustion process will degrade the coolant until it goes too acidic. A simple PH test will indicate if the coolant is 'off' and thus a flush and new coolant are called for. You also need to keep the overflow bottle in play as it allows the system to 'breath' during its operation. Hope this helps.