What is the purpose of the small pipe from the top of the radiator expansion tank?  

Have replaced the tank because it was cracked but the small pipe connector would not detach and ended up being broken.  Have refitted the new tank and joined the small pipe to the expansion tank using a jubilee clip behind the connector square section.  Am not sure how well this will hold since the clip innards seem to be hard plastic, which does not tighten down very well.  Should this be OK?

If not, can just the clip be purchased but seems to be heat shrunk to the pipe, so would we need to buy the complete pipe?  Where does the pipe connect to at the other end - seems to disappear around the back of the engine somewhere?

Any advice, gratefully received.

I think it's just to release air/water if it boils over and i think it connects where the thermostat is what i can see on mine.

 

 

 

14 hours ago, Fiesta51 said:

If not, can just the clip be purchased but seems to be heat shrunk to the pipe, so would we need to buy the complete pipe?  Where does the pipe connect to at the other end - seems to disappear around the back of the engine somewhere?

You should be able to get the complete pipe with the clips already attached from Ford. They are not usually very expensive.