lossing some amount of coolant, getting the burning smell as it hitting hot parts, felt where the coolant pipes connect to heater matric pipes under the bonnet and there is water. do these pipes just push..cant tell .

thank you. the pipes run from front to the back ,where they fit to heater pipes, is the hbv more over to the right, ie passenger side, have looked and not sure if hbv was leaking the water would run down to where its wet, it just fills wet at end if pipe and not all the way along it.. does any one know the part number for hbv on 2.5v6 estate 2000 x reg and i will get one incase... thanks ....paul