British FM killing the fun of the game for allied pilots.

[Kurfürst]

Originally Posted by NZtyphoon

the lower operating temperature of the engine on this mix - also used by the Merlin XII - helped TBO and reliability. In theory the CLOD Merlin XII should not be overheating as much as it is right now. I'm not sure about the temperature difference of 70°C as quoted so I'll dig a little more.

Pure Glycol has about twice the boiling point of water but only about half the heat capacity (plus its an anti-freeze). So in effect the coolant (and engine!) temperatures are going to be much higher (since the coolant agent can carry away about half the heat), but I reckon it would boil much later. Hence why it is used in a mix with water. It would also explain why the Hurri I and Spit I overheats so fast.

Engine temperatures are a function of coolant capacity, coolant type, coolant circulation capacity and heat transfer capacity of the radiators. The amount of pressurization the cooling system also raises the boiling point.

What was the coolant capacity of the Spit and Hurri Mark Is, how many gallons/liters? Are there any cooling trials available for these aircraft?