easy.. this requires a new gasket set.. only undo the FIRST set of allen key bolts to free the plastic head whicvh is held in place by a metal cowling.. all pulls apart so pull it apart over a bowl to avoind losing small springs that are in there... only a muggins would be unable to work out which gasket goes where, so I wont patronise you here... old gaskets may show NO signs of wear to the untrained eye.. I suspect its the thin triangular gasket, but while you have it open, you can change all of them
Julian Pearson, May 2011
