a) The plug at the end of the breather pipe is to be removed and breather fitted on to the pipe along with the fly nut. b) It is necessary before fitting the breather to observe the colour of the silicagel. If necessary, the breather should be opened and the silicagel properly dried up so that its colour is perfectly bluish. c) The chamber at the bottom of the breather should be filled in with dry transformer oil up to the level marked.