FT100 MkIII - expansion tank "overflow hose"

[TransitNoob123]

Hello

Transit 100 Mk III petrol engine

Very basic noob question here. Coming out of my coolant expansion tank are three hoses. Two are the same size, and connect to the radiator and the thermostat, respectively. There is a third, thinner hose sitting slightly higher, just below the tank cap. Right now the other end is not connected to anything, it just hangs down below the engine. On this diagram:

http://www.fordopedia.org/parts-catalog ... -mk3/F2.10

it is part 20, given as an overflow hose.

Is it supposed to be connected to anything? Or is it overflow as in "overflow out onto the ground if pressure is too high"?

Thanks in advance. Lots more rookie questions to come

[Chug]

As you suspect it is the overflow in case the radiator cap is overpressurised to release coolant and pressure, it just goes down to the ground and is not connected anywhere.

[TransitNoob123]

Thanks Chuggy, much appreciated